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ORTEC digiDART Operator Manual

1. Amplifier Amplifier 2 ADC Stabilizer High Voltage 5 11 1 1 Manual Add Field Data About Status Presets MDA Preset Nuclide Report Nuclides can be added to the list sepa bp et _ dd New u l54 643 Bie UO UUU using the library to assist in the l Update region definition or manually To gt Delete add a nuclide manually enter the Library Report nuclide name ROI start and end O E Nuclide Eu 154 Factor 1 0000E 000 channels multiplicative factor Low ROI 543 Units and units in the Report section Energy 123 14 High ROI E63 Select hom Db Now press Add New to add this nuclide to the list The units need only be entered once since they are the same for all nuclides in the table Figure 42 Nuclide Report Tab 5 11 1 2 Library Add To use the library to aid in the definition select the nuclide from the library nuclide drop down list Now select the gamma ray energy from the Energy drop down list This defines what gamma ray to use Now Press the Select from Lib button in the Report section This will update all the entries in this section and show as a yellow band the region to be used in both the expanded spectrum and the full window Now press Add New to add this nuclide to the list 5 11 2 Edit To change any of the current nuclides select the nuclide in the list use the scroll bars if needed This will show the current settings for this nuclide Make any chang
2. dayb n S 18 Preset Settings oce oi peta bei eel y ie 16 QUICK referen Enes ass a oie E CEPS 116 Spectrum Directory sas dn ER Eb 25 Spectrum Memory 225 bee ER Eb 24 Stabilizer Settings 5 55 54 x den Rebum 21 Nuclide Report 12 date esce deed 26 37 Calculations 5 4 55 uan beo ha bu 57 SeL up ROIS lt A ecrh sus z eer eyb a 11 Operating systems e cioe raa KK KK A KK KK 4 Pas WOES del alba Eu ka Pede Gaba 37 adimiisttalor s nun wa CP ER Eb 22 enter PASSWORD su ibo cu ta bereya S CEP 23 USEE e na y k Sab oye a db A Lio 22 Preset Settings menu 33 05 9482 beh ER RE 16 Preset sepa sa 545 0533522 2an 2 2 ka Pesce ee bae 36 Quick reference to menus 152 Rx Rb 116 Regions of interest ROIs Nuclide Report setup 11 peak info at current marker position 12 ROIs on the spectrum display 36 BesolutloB s iau sam taba ra dob dee hab aur 61 Sample ID description 10 Shaping controls 6 use yc SG RES 34 45 SMART 1 detector shutdown mode digiDART 49 Spectrum acquiring spectra 53 te KK RR KK K gt 40 AT cle SAR ND DD peta bai eile bees 25 disable with password 23 39 download to PC 4 23 04 coi Lex KK gt 41 enter sample ID description 10 live spectrum memory 4 2 marker and status line parameters 32 spectrum collection and storage 2 digiDART Portable HPGe MCA User s Manual START
3. SHOW_HV_ACTUAL Returns the value of HV actually on the detector 97 digiDART Portable HPGe MCA User s Manual SHOW HV HEALTH Returns the status of the state of health for the detector as reported by the DIM or SMART 1 SHOW HV RECOMMEND Returns HV in ASCII from SMART 1 detectors SHOW HV TARGET Under normal operation the HV will go to this value when the HV is enabled Reports the current HV setting see SET HV and the status of the HV power supply in the form DvvvvvsssssccccCR where vvvvv represents the HV setting and sssss represents the status of the HV bias supply as a 16 bit decimal number with the following bit definitions Bit 0 LSB Bias supply polarity O positive 1 negative Bit 1 Bias supply overload O overload 1 normal Bit 2 HV enabled O disabled 1 enabled Example Responses D0200000003077 lt CR gt 2000 V negative not overloaded disabled D0200000002076 lt CR gt 2000 V positive not overloaded disabled D0200000007082 lt CR gt 2000 V negative not overloaded enabled SHOW_HV_POLARITY This returns the HV polarity setting in the digiDART as a F record Responses INEG lt CR gt The HV is set to negative IPOS lt CR gt The HV is set to positive SHOW_ID Reports the sample ID string as was previously set by the SET_ID command The sample ID string is stored with each spectrum acquired in field mode and is restored with the field mode spectral data by the MOVE command E
4. Eds 24 2 22 0 cC Oy N uchde RO DOT c4 ent esit opor Pa ER S np ER eee edes 26 3 INSTALLATION AND STARTUP 4 iet ende Gan kk kk IP Ebo d kk kk k E 27 3 1 Software and Hardware Installation 0 KK KK KK KK KK KK K KK KK KK KK KK KK IK 27 3 1 1 Install MAESTRO 32 and the CONNECTIONS 32 Driver Update Kit 27 3 1 2 Connect the digiDART to the USB Port on the PC 27 3 1 3 Run the MCB Configuration Program to Build a List of Available Detectors 27 3 1 4 Attaching More Than One digiDART to the PC XV RR 27 3 1 5 Connecting to and Disconnecting from the PC XV 28 digiDART Portable HPGe MCA User s Manual 920 CABINS esa a22 oos vie Sue neat que 4 deoa pM d E oA 28 3 3 Turning the Power On and Off 4 kk kk kk kk kK KK KK KK KK KK KK ERAI ved ce YS 29 SA Chanpitip the Battery s lt 5x51A4 yx ose oe eee eee RES Kl ete rue esr quet Pus 29 4 USING THE DIGIDART IN FIELD MODE kk kk kk KK kk kk kk kk kk eee 31 4 Normal Operati Ol 5s ceranae a HUE V Kik RE ERR Dad ai aE DEA eS 31 B N BE IUD RTT 31 X51525 Del CIO u scout veste d OR dst ome u kak o eames Geil pfe Gy e E WAN 32 4 1 3 Stored Spectrum Memory v cosTeYes eR kK KK KK KK KK KK KK KK KK KK Let 32 4 1 4 Spectrum Status Parameters kk kk kk kK KK KK KK KK KK KK KK KK KK KK KK KK 32 d AD serrana eren meus peas xb Meta m ie a RE aoe cta uias Quee a vba dens 33 2 1 6 Nmplitier iue LETTO ee CR ries aget ge
5. Figure 5 Nuclide Report ROIs To set up a nuclide ROI press its number to display the submenu shown in Fig 6 Press 1 Change Label to enter the nuclide name The Chance Label name can be 6 characters long for example AM 241 Change Units Change Start Channel See Section 2 1 2 for instructions on entering the various Change ROI Length characters j Seay Constant Show ROI Setup Press 2 Change Units and enter the desired unit of measure text up to 6 characters The same units label is used for all entries and is only entered once Figure 6 Set Up the ROIs Next press 3 Change Start Channel and enter the start channel for the region The start channel should below on the low energy side of the peak in the background The first 3 channels are used for the low energy background Press 4 Change ROI Length and enter the width of the region which must be at least 7 channels The width should stop above on the high energy side of the peak in the background so that the region is approximately centered on the peak channel The last 3 channels are used for the high energy background Next press 5 Change Constant The constant is multiplied times the net peak count rate to give the value shown on the report To report activities you need to know the branching ratio yield for this gamma ray for this nuclide and the efficiency The branching ratio can be found in any gamma ray library e g NuclideN
6. IF lt CR gt TTL or ORTEC shutdown set SHOW_DET_SNUM This command responds with the detector serial number stored in the DIM Response FP40175 Serial number P40175 SHOW_DET_VERSION Returns the DIM firmware version Examples FNAIDO00 Nal DIM firmware version FSMDT000 SMART 1 firmware version SHOW_DEV Shows the currently selected device Always 1 for digiDART SHOW_FEATURES Responds with four 32 bit masks indicating which features are present in the MCB See Appendix 7 3 for a complete description of each bit in the mask Example Response FEATURES 02285062207 02014941185 00000000000 00000000000 SHOW_GAIN_ADJUST Returns the gain stabilize amplifier setting SHOW_GAIN_CHANNEL Reports the current center channel for the stabilizer gain peak See also SET_GAIN_CHANNEL Responses C00000087 CR Gain channel has not been set C00002089 CR Gain channel is channel 2 lowest possible channel C16382107 CR Gain channel is channel 16382 highest possible channel 95 digiDART Portable HPGe MCA User s Manual SHOW GAIN COARSE Returns the coarse gain for the digiDART internal amplifier In operation the resulting signal gain is the product of the coarse gain the fine gain and the super fine gain used by stabilizer The coarse gain is returned in terms of an integer gain multiplier Responses C00001088 lt CR gt Coarse gain reported as 1 C00002089 lt CR gt Coarse gain reported as 2
7. discusses this tradeoff and contains a guide to choosing rise time accord Figure 33 Amplifier 2 Tab ing to count rate The value of the rise time parameter in the digiDART is roughly equivalent to twice the integration time set on a conventional analog spectroscopy amplifier Thus a digiDART value of 12 us corresponds to 6 us in a conventional amplifier Starting with the nominal value of 12 0 you should increase values of the rise time for better resolution for expected lower count rates or when unusually high count rates are anticipated reduce the rise time for higher throughput with somewhat worse resolution 45 digiDART Portable HPGe MCA User s Manual Use the up down buttons to adjust the rise time within the range of 0 2 us to 23 0 us The most recent settings are saved in the digiDART firmware even when the power is turned off For the more advanced user the InSight mode allows you to directly view all the parameters and adjust them interactively while collecting live data To access the InSight mode go to the InSight section and click on Start The Rise Time value is for both the rise and fall times thus changing the rise time has the effect of spreading or narrowing the quasi trapezoid symmetrically The Flattop controls adjust the top of the quasi trapezoid The Width adjusts the extent of the flattop from 0 3 to 2 4 us The Tilt adjustment varies the flatness of this section slightly The Til
8. False response to a SHOW command no checksum Jxxxxxyyyyy ccc CR Response to SHOW CONFIGURATION command Mxxxxxxxxxx ccc CR Response to SHOW STATUS command Nxxxyyyzzzccc lt CR gt XXX yyy and zzz are 8 bit unsigned numbers 8 1 4 Command Catalog This section lists each command with a description of its operation The descriptions include a list of any unusual responses that may result As described in previous sections the usual 74 8 FIRMWARE COMMANDS AND RESPONSES response from a command is a 76000000069 CR response which represents a macro error code of 0 and a micro error code of 0 no errors All execution error responses if any are listed for each command Though syntax and communication error responses may result from any command in practice these error responses rarely occur on systems with reliable communication hardware running debugged software Refer to Section 8 1 2 for information about error responses In the following catalog the commands are listed in alphabetical order each starting with a command prototype line Upper case letters numeric digits blank spaces and special symbols such as the underscore _ and comma in the prototype line are literal text to be sent to the MCB exactly as they appear Lower case letters in the prototype line represent numeric values as described in the accompanying text and should not be sent literally to the MCB but should be replaced by an appropriat
9. LIST_GAIN_COARSE Lists the valid coarse gain settings LIST_GAIN_FINE Lists the valid fine gain settings LIST_HV Lists the valid high voltage settings 80 8 FIRMWARE COMMANDS AND RESPONSES LIST ROI SAMPLE Lists the valid ROI sample settings LIST SHAP CUSP Lists the valid cusp shape settings LIST SHAP FLAT Lists the valid flattop width settings LIST SHAPE RISE Lists the valid rise time settings LIST SHUT Lists the valid shutdown settings LIST TRIG SAMPLE Lists the valid sample trigger settings MOVE spectrum number This command copies the specified stored spectrum calibration and all parameters to the live memory along with the live time real time start time and date live time preset real time preset ROI integral preset ROI peak preset and data ID string if any see SET ID Spectrum number can be any value from 1 to the number of spectra stored Execution Errors 131128085 lt CR gt An invalid spectrum number was specified No action was taken 131135083 lt CR gt Command was attempted while spectrum acquisition was in progress No action was taken OFF Turns the digiDART off OPEN_FILE filename ext A filename is needed to open a file Begins the download of a file to the RAM Disk by opening filename ext on the RAM Disk See WRITE_FILE and CLOSE_FILE OPEN_FILE_FLASH Begins the download of a new FLASH ROM DISK This command removes all files on the RAM Disk except autoexe
10. Reports the time of the last START command in the form Nhhhmmmsssccc CR where hhh represents a 3 digit integer hour 0 through 23 mmm represents a 3 digit integer minute 0 through 59 and sss represents a 3 digit integer second 0 through 59 See also SET TIME START SET DATE START and SHOW DATE START Example Responses N010054017052 lt CR gt Time returned 10 54 17 10 h 54 min 17 s N020013037050 lt CR gt Time returned 20 13 37 20 h 13 min 37 s SHOW TRIG SAMPLE Reports the trigger source in InSight Mode Responses FOLLD LLD is source FIPKD Peak detect is source F2RANDOM Trigger happens randomly F3Gate Gate Input triggers the waveform SHOW TRIGGER SPECIAL Not used included for backward compatibility 107 digiDART Portable HPGe MCA User s Manual SHOW TRUE Reports the contents of the true time counter in units of 20 ms 50 ticks s See also CLEAR COUNTERS and SET TRUE Responses G0000000000075 lt CR gt True time reported as 0 ticks G0000000001076 lt CR gt True time reported as 1 tick 20 ms G4294967295132 CR True time reported as 4294967295 ticks over 23000 days SHOW TRUE PRESET Reports the current true time preset in units of 20 ms 50 ticks s See also CLEAR PRESETS and SET TRUE PRESET Responses G0000000000075 lt CR gt True time preset reported as disabled G0000000001076 lt CR gt True time preset reported as 1 tick G4294967295132 CR True time preset report
11. nouns and modifiers in the command header are mnemonic words such as the verb ENABLE or the noun OVERFLOW that relate to the function performed by the MCB API when it executes the command The first four letters of any word will always be enough to uniquely identify the word when composing commands for an MCB API For example the command ENABLE OVERFLOW PRESET can be abbreviated to ENAB OVER PRES Numeric parameters follow the command header separated by one or more spaces Specific commands require up to three parameters separated by commas which specify numeric quantities related to the operation of the MCB such as live time or conversion gain The command SET WINDOW 0 16384 has two parameters 0 and 16384 which set the window of interest to start at channel 0 and continue for 16384 channels Some parameters listed in the command dictionary are considered optional and are distinguished from mandatory parameters by being surrounded by brackets in the command prototype line 71 digiDART Portable HPGe MCA User s Manual e g SET WINDOW start length Commands that have optional parameters may be sent to the MCB API without the optional parameters in which case the behavior will be changed as explained in the command description An optional checksum may be added to the end of any command sent to MCB API The checksum is a 1 byte unsigned integer sum of all of the characters in a command treated as unsigned integers up to and includ
12. the LLD setting ULD Digital upper level discriminator set in channels Hard cutoff of data in channels above the ULD setting Software Ratemeter Monitor the input count rate from the digiDART display or software Stored Spectrum Memory 1 5 MB of memory available for storage of spectra and collection parameters Any combination of spectrum sizes can be stored Presets Multiple presets can be set by software or keypad on any or all of the following e Real Time Stops data collection when the real time reaches this value in increments of 1 s e Live Time Stops data collection when the live time reaches this value in increments of 1 s e ROI Integral Integral count stops data collection when the sum of all ROI channels reaches this value ROI Peak Peak count stops data acquisition when any ROI channel reaches this value maximum value of 222 1 counts 4 billion Uncertainty Sets the required statistical accuracy on a key peak for example stop counting when the activity of Co is known to be better than 5 Patent number 5 912 825 64 7 SPECIFICATIONS e Multi Nuclide MDA Stops data collection when the value of the minimum detectable activity MDA for up to 20 user specified MDA nuclides reaches the needed value The presets are implemented in hardware so do not require the computer to be polling the digiDART for the preset to operate See Section 6 2 for details on the MDA preset calculation e Data Overflo
13. 0 to 65535 996 in steps of 1 256 The add in will convert the value to an unsigned long with a binary point between the left of the least significant byte SET NUCLIDE DESC PeakNumber NucLabel Sets the nuclide label for the specified peak to the specified value The label must be 6 characters or less SET NUCLIDE UNITS units Sets the activity units to the specified string The string may be no more than 6 characters 87 digiDART Portable HPGe MCA User s Manual SET PEAK PRESET count Sets the ROI peak preset to the specified count During data acquisition when the contents of any channel of a device that has the ROI flag set reaches the peak preset count the preset is complete and the acquisition is stopped The actual number of counts in the ROI peak may exceed the preset value by a small number of counts due to the pipelined architecture of the digiDART Setting a peak preset to 0 counts disables the preset The peak preset may be set to from 0 disabled to 2147483647 counts See also CLEAR PRESETS and SHOW PEAK PRESET Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_PZ num This sets the pole zero to num which must be between 0 and 4095 See also ENABLE _PZ AUTO SHOW_PZ and DISABLE PZ AUTO SET_RADIX_BINARY Not used included for backward compatibility SET ROI start chan number of chans Sets the ROI flags for the specified
14. 001 012 and year as a 3 digit integer number from 000 099 See also SET DATE START Responses N001001088052 lt CR gt Date reported as Jan 1 1988 N031012099059 lt CR gt Date reported as Dec 31 1999 N001001000036 lt CR gt Date reported as Jan 1 2000 N031012087056 lt CR gt Date reported as Dec 31 2087 SHOW_DATE_START Returns the day month and year of the acquisition start date in the form dddmmmyyy The day is returned as a 3 digit integer number from 001 031 month as a 3 digit integer number from 001 012 and year as a 3 digit integer number from 000 099 See also SET_DATE_START Responses N001001088052 lt CR gt Date reported as Jan 1 1988 N031012099059 lt CR gt Date reported as Dec 31 1999 N001001000036 lt CR gt Date reported as Jan 1 2000 N031012087056 lt CR gt Date reported as Dec 31 2087 SHOW_DEBUG Shows the debug level of the software SHOW_DELAY_COLLECTION Shows the width of the PUR signal setting See also SET DELAY COLLECTION Responses DEL_COLL 0000000000001 6 Delay collection 1 6 seconds SHOW_DELAY_SAMPLE Shows the Delay Sample setting See also SET DELAY SAMPLE Responses C00003090 The sample number is 00003 and 090 is the checksum 94 6 FIRMWARE COMMANDS AND RESPONSES SHOW DET SMART Indicates whether the detector is SMART 1 and the shutdown mode is set for a SMART 1 HPGe Detector Responses are true and false Responses IT lt CR gt SMART 1 shutdown set
15. C00004091 lt CR gt Coarse gain reported as 4 C00008095 lt CR gt Coarse gain reported as 8 C00016094 lt CR gt Coarse gain reported as 16 C00032092 lt CR gt Coarse gain reported as 32 SHOW_GAIN_CONVERSION This command returns the conversion gain Responses C00512095 lt CR gt Conversion gain reported as 512 channels C01024094 lt CR gt Conversion gain reported as 1024 channels C02048101 lt CR gt Conversion gain reported as 2048 channels C04096106 lt CR gt Conversion gain reported as 4096 channels C08192107 lt CR gt Conversion gain reported as 8192 channels C16384109 lt CR gt Conversion gain reported as 16384 channels SHOW_GAIN_FINE Returns the current fine gain setting See SET_GAIN_FINE Sample Response GAIN_FINE 0000000000000 5 Parameter is set to 0 5 SHOW_GAIN_POLARITY Returns the polarity of the amplifier input as F records Responses INEG lt CR gt The amplifier input is set to negative IPOS lt CR gt The amplifier input is set to positive SHOW_GAIN_STABILIZATION 96 Reports the state of gain peak stabilization See also ENABLE_GAIN_STABILIZATION and DISABLE_GAIN_STABILIZATION Responses IT lt CR gt Gain stabilization is currently enabled IF CR Gain stabilization is currently disabled 6 FIRMWARE COMMANDS AND RESPONSES SHOW GAIN WIDTH Reports the current width for the stabilizer gain peak See also SET GAIN WIDTH SET GAIN CHANNEL and SHOW GAIN CHANNEL Respon
16. Channel and Width fields to enter the channel limits directly or click on Suggest Region If the marker is positioned in an ROI around the peak of interest Suggest Region reads the limits of the ROI with the marker and display those limits in the Start Chan and Width fields The ROI can be cleared after the preset is entered without affecting the uncertainty calculation If the marker is not positioned in an ROI the start channel is 1 5 times the FWHM below the marker channel and the width is 3 times the FWHM The net peak area and statistical uncertainty are calculated in the same manner as for the MAESTRO Peak Info command which is discussed in the Software User s Manual Note that the Suggest Region button is not displayed during data acquisition Marking the Overflow checkbox terminates acquisition when data in any channel exceeds 27 1 over 2x10 counts 5 10 MDA Preset Tab The MDA preset Fig 41 can monitor up to 20 nuclides at one time and stops data collection when the minimum detectable activity for each of the user specified MDA nuclides reaches the designated value The MDA preset is implemented in the hardware The formulas for the MDA are given in various textbooks and in the Analysis Methods chapter in the GammaVision 32 Software User s Manual and can be generally represented as follows MDA a y b c Counts Live time Eff Yield See also Section 6 2 The coefficients a b and c are determined by the MDA formula t
17. FILE FLASH COMP Selects the computer mode for the communication replies DISABLE BLRE AUTOMATIC Disables the automatic determination of baseline restorer time constant See also ENABLE BLRE AUTOMATIC SET BLRE and SHOW BLRE DISABLE DISPLAY Disables the spectrum display when the digiDART is disconnected from the PC DISABLE GAIN STABILIZATION Stops stabilization of the gain peak while data is being acquired The gain stabilization adjustment is held at its current value until either gain stabilization is reenabled with the ENABLE GAIN STABILIZATION command or reinitialized with the INITIALIZE GAIN STABILIZATION SET GAIN PEAK or SET GAIN WIDTH command See also SHOW GAIN STABILIZATION DISABLE GATE ROUTE Disables the use of the gate input for routing spectra this command is included for backward compatibility DISABLE HV Turns off the high voltage enable signal of the digiDART See the section on the bias supply for more information about the high voltage output See also ENABLE HV and SHOW HV DISABLE NAI Switches the stabilizers to Ge mode See ENABLE NAI DISABLE OPTI NEED Disables the reporting of an error when the digiDART has not been optimized DISABLE OVERFLOW PRESET Disables the overflow preset Channels that receive a count when they contain 2147483647 counts the maximum number of counts will roll over to zero counts if the overflow preset is disabled See also ENABLE OVERFLOW PRESET and SHOW OVERFLOW PRESET 7
18. List on the PC does not include the digiDART Run the MCB Configuration program as discussed in Section 3 1 3 or the MAESTRO Software User s Manual If this does not resolve the communication issue contact our Global Service Center 42 5 USING THE DIGIDART WITH MAESTRO The digiDART is intended for completely independent operation with no PC required However when you connect it to a PC running ORTEC CONNECTIONS 32 spectroscopy applications such MAESTRO or ScintiVision you can use it as a high performance spectrometer digital MCA When you disconnect from the PC any changes you have made to the hardware settings via PC will remain in effect until changed from the keypad Be sure to install the accompanying MAESTRO 32 MCA Emulator application and if supplied the CONNECTIONS 32 Driver Update Kit These contain the most up to date drivers for the digiDART and other ORTEC hardware If you have any questions about software hardware compatibility contact your ORTEC representative or our Global Service Center The MAESTRO Software User s Manual contains complete instructions on software installation and configuration of the MCBs attached to your PC When installing MAESTRO choose the USB Based Instruments selection to install the correct driver for the digiDART The rest of this chapter discusses the hardware setup dialog you will see within MAESTRO ScintiVision and all other ORTEC CONNECTIONS 32 software when you click on Acquire MCB P
19. STOP CLEAR STORE buttons 7 storage capacity sese ose e od KK KK 3 stored spectrum memory 2 view status line parameters 32 view monitor erase stored spectra 24 view transfer stored spectra via PC 49 Spectrum Memory menu 24 State of health SOH 14 34 50 51 Troubleshooting 24 0 0 eie Ee n DEREN NES 42 View MCA settings status 10 Zero stabilizer 4 34 se Pak eA y ES 21 37 47 60 operation details 25 ovs eb Res 60 114 INDEX 115 sBulnas yuan MaIA 0 qes 019Z ezijeniul 8 UIPIM QelS 019Z 2 jeuueu e ue9 qeis 0187 9 i u v UIPIM GEIS ure Jeuueu 491u92 qejs UWY Z uoneziliqeis uleg eiqeua pesn sej q 0048891 so 092886 0 lt SHOW 19 48 60 61 01 33H52 4 00 22 60 81 01 z X33499 9 St LL 60 BL OL L N33H2 S SL St ZL 82 90 S00 T1IH t 82 61 21 86 90 f00 TIIH 48 28 91 86 90 00 T1IH Z LZ SS SL 87 90 200 T7IH L 80 14 60 L0 LO LOO TTIH 0 Asoyoasg uinoeds sbumes elA 6 VAIN 18215 8 SWEN PI NN 19447 Z pI8 A ouaroija 1e u3 9 4y6ua7 JOH Je u3 S uueu MOT 19443 209 VAN 19 u3 enjoy 19s24d VOW 1943 Z Gasp ese d VAN 1947 L 3ALLOV qanave d qa18vsia aztevsia a ER q 1svs q 3N LOY 3AILOV a 1avsld 3ALLOV sBumes 1ue no Mel S ewo v ain am e ule uoIS19AUO2 sbumes M NA E VHd epo Aeidsiq jas
20. Shows the type of HV shutdown selected Responses FORT ORTEC mode selected FTTL TTL mode selected FSMI SMART 1 mode selected SHOW SHUT ACTUAL Returns the current status of the bias remote shutdown input signal This command is valid whether the bias supply is turned on or off Responses IT Shutdown is active supply is shut down or can t be turned on IF Shutdown is inactive supply is on or can be turned on SHOW SNUM Responds with a F record indicating the serial number of the digiDART Response F100 Serial Number 100 105 digiDART Portable HPGe MCA User s Manual SHOW SOH Returns the state of health word for the detector SHOW SPECTRUM num Copies the desired spectrum num from the stored spectrum memory to the active spectrum memory num is a number between 0 and the value returned by SHOW SPECTRUM COUNT SHOW SPECTRUM COUNT Returns with a response where the number indicates the number of spectra in the stored spectrum memory SHOW STATUS Returns system status information in the following format Milililiilittttttttttaaaaahhhhhccc CR where llllllllll represents the live time as returned by the SHOW LIVE command tttttttttt represents the true time for the current device as returned by the SHOW TRUE command aaaaa represents the active device mask as returned by the SHOW ACTIVE DEVICES command and hhhhh represents the hardware status which is an ASCII representation of a 16 bit decimal n
21. Time 4 Flatto 5 Pole Zero 6 Baseline Restore 7 Optimize 8 Preamp Type 9 Input Polarity 0 View Current Settings Figure 14 Amplifier Settings This sets the amplifier fine gain to any value between 0 45 and 1 00 3 Rise Time This sets the rise time to values between 0 8 and 23 0 Values less than 0 8 are automatically adjusted up to 0 8 Values greater than 23 0 are adjusted down to 23 0 14 2 THE DIGIDART 4 Flattop This sets the filter flattop width to values between 0 3 and 2 4 Values less than 0 3 are automatically adjusted up to 0 3 Values greater than 2 4 are adjusted down to 2 4 5 Pole Zero This shows the PZ dialog where you select either manual or automatic PZ Note that if you use the Optimize function it automatically PZs the digiDART Enter Manual PZ Setting This allows you to enter the PZ value to any number between 1 and 4095 2 Perform Auto PZ This performs the auto pole zero The unit must be collecting data with a dead time less than 10 for best results The PZ process does not start until you reply that the unit is ready to start by pressing 1 on the next dialog You can press MENU ENTER to return to the previous menu at this time During the PZ process the current PZ value is displayed To abort the PZ process press the MENU ENTER key 6 Baseline Restore This opens a dialog listing three Baseline Restore settings Select the desired setting by pressing 1 2 or 3 After
22. a resolution of 20 milliseconds ms since the MCB clock increments by 20 ms Real time means elapsed time or clock time Live time refers to the amount of time that the MCB is available to accept another pulse i e is not busy and is equal to the real time minus the dead time the time the MCB is not available Enter the ROI Peak count preset value in counts With this preset condition the MCB stops counting when any ROI channel reaches this value unless there are no ROIs marked in the MCB in which case that MCB continues counting until the count is manually stopped 53 digiDART Portable HPGe MCA User s Manual Enter the ROI Integral preset value in counts With this preset condition the MCB stops counting when the sum of all counts in all channels for this MCB marked with an ROI reaches this value unless no ROIs are marked in the MCB The Uncertainty preset stops acquisition when the statistical or counting uncertainty of a user selected net peak reaches the value you have entered Enter the Preset in value as percent uncertainty at 1 sigma of the net peak area The range is from 99 to 0 1 in 0 1 steps You have complete control over the selected peak region The region must be at least 7 channels wide with 3 channels of background on each side of the peak As the uncertainty is calculated approximately every 30 seconds the uncertainty achieved for a high count rate sample might be better than the preset value Use the Start
23. by pressing 1 Enable HV Finally check all of these operations by pressing 4 to view the HV settings If no detector is connected the readings have no meaning 4 1 3 Stored Spectrum Memory Next check the amount of memory available for stored spectra Press MENU ENTER then 8 Spectrum Memory 3 Spectrum Directory to display the contents and remaining capacity of the stored spectrum memory The display format is sequence Identifier start month and day start time The bottom of the screen displays a message saying x of y bytes used If you expect to need more than the remaining storage space you must clear out the existing spectra If you want to save these spectra you must download them to PC After download clear the digiDART memory by pressing MENU ENTER 8 Spectrum Memory then 2 Erase All If no more stored spectrum memory is available you can if you wish collect a final spectrum and leave it stored in RAM Once you ve docked to the host PC download that final spectrum first then download the spectra from stored spectrum memory 4 1 4 Spectrum Status Parameters The digiDART displays two data acquisition parameters in real time at the top of the spectrum see the top of Fig 31 page 36 To set up this status line press MENU ENTER and press 4 Status Line to display the numbered list of parameters Cursor location energy 2 Cursor location channel 32 4 USING THE DIGIDART IN FIELD MODE Live
24. checksums SHOW CONFIGURATION MASK Returns two masks the first of which can be anded with data from the MCB to clear the ROI bit from the data When the second mask value is anded with data from the MCB the data bits are removed and only the ROI bit remains Response CONF MASK 02147483647 02147483648 SHOW CONFIGURATION UART Reports the baud rate parity option number of data bits and number of stop bits for the serial interface Responses F09600N81 9600 baud no parity 8 data bits 1 stop bit F19200E82 19200 baud even parity 8 data bits 2 stop bits F02400071 2400 baud odd parity 7 data bits 1 stop bits SHOW CORRECTION FLAT Shows the flattop correction value See also SET CORR FLAT Responses CORR FLAT 000000000000000 SHOW CRM Returns the current reading of the count rate meter Response G0000050781096 Current input count rate is 50781 counts s SHOW DATA APPLICATION string If string matches string1 in a previous SET DATA APPLICATION command then string2 from that command is returned The response is a F record Execution Errors 131138085 lt CR gt The specified string could not be matched 93 digiDART Portable HPGe MCA User s Manual SHOW DATE Returns the day month and year of the current date as maintained in the battery backed up real time clock in the form dddmmmyyy The day is returned as a 3 digit integer number from 001 031 month as a 3 digit integer number from
25. detectors have positive output and GMX LEPS and LOAX detectors have negative output Press MENU ENTER 6 then 2 to show the menu of amplifier settings Press 1 and then 2 Press MENU ENTER 3 times to return to the spectrum display Press 849 to show the complete spectrum Put a known source such as 37Cs or Co in front of the detector and press STOP CLEAR then START to begin collecting a spectrum You should see a spectrum in the display and see the live time on the upper right If the peaks are not where you want them in the spectrum press MENU ENTER 6 2 and then 1 or 2 depending on how far from ideal the peaks are Then adjust the gain to a lower or higher value Press MENU ENTER 3 times to return to the spectrum display then press STOP 33 digiDART Portable HPGe MCA User s Manual CLEAR and START to collect another spectrum Adjust again if needed or continue with the next step 4 1 7 Rise Time and Flattop The rise time should be set for the count rate and resolution you expect Of course you can t improve the resolution beyond the capabilities of the detector but you can adjust the digiDART setting for the best resolution at any count rate For most field work the rise time is set to 12 and the flattop is set to 1 This corresponds to the analog shaping time constant of 6 microseconds which is the setting used for detector test and specification If the count rate is expected to be high then shorte
26. gt Maximum count was found in channel 16383 SHOW PEAK PRESET Reports the value of the ROI peak preset See SET PEAK PRESET for information about the ROI peak preset Responses G0000000000075 lt CR gt Peak preset disabled G0000000001076 lt CR gt Peak preset set to 1 count G2147483646120 lt CR gt Peak preset set to 2147483646 counts G2147483647121 lt CR gt Peak preset set to 2147483647 counts SHOW_PZ Displays the PZ setting See also SET_PZ Responses PZ_ENA 002200 Pole zero enabled and set to 2200 PZ_DIS 001000 Pole zero disabled and set to 1000 103 digiDART Portable HPGe MCA User s Manual SHOW PZ AUTOMATIC Shows the state of the automatic PZ See also SET PZ AUTOMATIC Responses IT lt CR gt Pole zero enabled IF lt CR gt Pole zero disabled TRP SHOW RADIX SHOW RATE ZDT SHOW REMOTE Not used included for backward compatibility SHOW ROI Used in conjunction with the SHOW NEXT command SHOW ROI reports the first continuous group of channels that have the ROI flag set The response is of the form Dsssssnnnnncce lt CR gt where sssss represents an integer number that is the number of the first channel of the first group of channels that all have their ROI bit set and nnnnn represents an integer number that is the number of channels in the group The SHOW_NEXT command is used to report the next group of channels that all have their ROI bit set Responses D0100000050078 lt CR gt
27. mode input sources Uncertainty statistical preset SET UNCERT PRES Features vary by input SHOW FEATURES depends on device segment multi input MCBs only Software selectable HV shutdown mode SET SHOW VERI SHUT Software selectable shaping time constants SET SHAP Explorable shaping time constants SHOW CONFIG SHAP Advanced shaping time SET SHAP RISE SET SHAPE FLAT etc Software selectable BLR ENA DIS SHO BLR AUTO SET SHO VERI_BLR SHOW STATUS command supported returns M record Overflow preset ENA DIS SHO OVER PRES Software enabled MicroNOMAD style audio clicker ENA DIS CLICK Software readable thermistor SHOW THERM Floating point fine gain SET SHO VERUI LIST GAIN FINE Software enabled pileup rejector ENA DIS SHO PUR SET VERI WIDT REJ Alpha style HV power SHOW HV CURRENT Software readable vacuum SHOW VACUUM Acquisition alarms ENA DIS SHO ALARM Hardware acquisition trigger ENA DIS SHO TRIG Ordinal numbers for shaping times SET SHAP 0 SET SHAP 1 Query gain ranges LIST VERI GAIN FINE COAR CONV Routable inputs SET SHOW INPUT ROUTE External dwell support ENA DIS DWELL EXT Selectable SUM or REPLACE MCS modes ENA DIS SUM External start of pass support ENA DIS SHO START EXT Explorable with MCS list commands LIST SOURCE LIST LLSCA amp LIST ULSCA Device supports the MDA preset Software selectable ADC type Matchmaker Has ability to daisy chain MCBs DART ZDT
28. parameter 131132080 lt CR gt Invalid number of command parameters 131134082 lt CR gt Invalid device or segment selected 131135083 lt CR gt Command not allowed while acquisition in progress 131136084 lt CR gt Command not allowed in current mode of operation 131137085 lt CR gt Hardware failure detected while processing command 8 1 3 Dollar Response Records SHOW and STEP commands respond with a single dollar response record followed immediately by a percent response record All valid dollar response records for each command are listed in the command dictionary The following list provides the general form of each dollar response record for the MCB API In this list lower case letters represent numeric values The letters ccc always represent an 8 bit unsigned checksum of all characters on the record up to but not including the checksum characters and lt CR gt represents the ASCII carriage return character Axxxccce lt CR gt xxx is a single 8 bit unsigned number Cxxxxxccc lt CR gt xxxxx is a single 16 bit unsigned number Dxxxxxyyyyyccc lt CR gt xxxxx and yyyyy are 16 bit unsigned numbers Exxxxxccc lt CR gt xxxxx is a single 16 bit alarm mask F ssss lt CR gt SSSS is a variable length ASCII character sequence no checksum is sent with this record Gxxxxxxxxxxcccc CR XXXXXXXXXX is a single 32 bit unsigned number IT lt CR gt True response to a SHOW command no checksum IF lt CR gt
29. rate are monitored at the bottom of the dialog 46 5 USING THE DIGIDART WITH MAESTRO Gate This control allows you to select a logic gating function With Field Data About Status Presets MDA Preset Nuclide Report this function Off no gating is per Amplifier Amplifier2 ADC Stabiizer HighVoltage formed that is all detector signals Gale Conversion Gain REB E are processed with the function in Off Coincidence a gating input signal Lower Level ise 50 zi must be present at the proper time Upper Level Disc 16383 for the conversion of the event in Anticoincidence the gating input signal must not be present for the conversion of the detector signal The gating signal must occur prior to and extend 500 nanoseconds beyond peak detect peak maximum Figure 34 ADC Tab Real Time Live Time 304 92 295 40 Count Rate 901 Conversion Gain Sets the maximum channel number in the spectrum If set to 16384 the energy scale will be divided into 16384 channels The conversion gain is entered in powers of 2 e g 8192 4096 2048 The up down arrow buttons step through the valid settings for the digiDART Upper and Lower Level Discriminators The Lower Level Discriminator sets the level of the lowest amplitude pulse that will be stored This level establishes a lower level cutoff by channel number for ADC conversions Setting that level above random noise increases useful through
30. s you wish to assign as the password If you make a 38 4 USING THE DIGIDART IN FIELD MODE mistake press CLEAR to erase the preceding character When finished press MENU ENTER to return to the General Settings menu To remove the password enter a single 0 then MENU ENTER To set or change the administrator password from spectrum display mode press MENU ENTER 7 General Settings 2 Change Administrator Password then enter the number s you wish to assign as the password If you make a mistake press CLEAR to erase the preceding character When finished press MENU ENTER to return to the General Settings menu To enter the administrator password and go to the administrator level from the spectrum display press MENU ENTER 7 3 Enter Password enter the number string and press MENU ENTER When you enter it correctly the password display closes and returns to the Main Menu If incorrect an Access denied message is displayed If you do not know the password press MENU ENTER to clear the Access denied message and return to the Main Menu NOTE There is no master administrator password If you lose this password contact your ORTEC service representative or our Global Service Center 4 1 17 Locking the Spectrum Display For use in sensitive areas the spectrum display can be locked so that it can only be viewed by an administrator e g an administrator password must be set for this feature to work When the a
31. the 24 volt supply DIM 12V State Df Health OK in the DIM has stayed within DIM 24v State Of Heath 24V State Of Health 1 lak 200 mV of 24 volts since the last time the SOH was cleared Detector Temperature State Of ERR DIM 12V State of Health This is OK if the 12 volt supply Figure 39 Status Tab in the DIM has stayed within 200 mV of 12 volts since the last time the SOH was cleared DIM 12V State of Health This is OK if the 12 volt supply in the DIM has stayed within 200 mV of 12 volts since the last time the SOH was cleared DIM 24V State of Health This is OK if the 24 volt supply in the DIM has stayed within 200 mV of 24 volts since the last time the SOH was cleared Temperature State of Health Not available for the digiDART High Voltage State of Health This is OK if the HV supply in the DIM has stayed within 200 V of specified bias voltage since the last time the SOH was cleared Shutdown State of Health This is OK if the detector shutdown has not activated since the last time the SOH was cleared Preamplifier overload State of Health This is OK if the preamplifier overload has not activated since the last time the SOH was cleared 51 digiDART Portable HPGe MCA User s Manual Security State of Health Not available for the digiDART Power State of Health This is OK if the power to the DIM was constant during the last spectrum acquisition 24 volts This is the curre
32. the Password 2 0 wiscw one kk kK KK KK KK KK KK KK KK KK KK KK sede 42 4 3 4 MAESTRO Does Not Connect with the digiDART S 3 42 5 USING THE DIGIDART WITH MAESTRO kk kk kk kk kk kk rene 43 Salz Amplifi Lab 2 3 6o cats d Os SU e eds Eae quiate he de pg rd d Eques 43 52 Amplifier bab s z eb EIER pex tont e d out o v o tu boi Vs 45 DOLUS DEO Tab do eee pts isset dee pd rotated eese Da i CUu fce DE 46 SARE LeTV PAE AD ada ea o uade On DR RI CUORE Oval d Mute bp we SR rx 47 3 5 High Voltage bab est xan ect e ES ER ee me Me eke Heed KA FEN A k Yi T EOS 48 S 0 Field ata 3b c seat orev heres eio dace Qe X Ta es NaEanNRaI a TITDDMDMI aE Eee qus 49 S5 About LAD ys set ee wer Xi n al DAD Kn WAD b EA EW 0n u ad E pU a EL ee Es 50 TABLE OF CONTENTS 3 8 tatus Tabs am cce baat Neth even Nerd ed Wert uid SI qu epu 50 329 Presets LAD des wea S du EX kun bicua qa dash p waive i SEE Ri cupa A R 53 3 10 MDA Preset Tabi Loses hw na t Ite es el sa e Fu x eee ee 54 3 Ib INuchde Report Dabo d bot te e ibo Roe d ue dte E whe ane ee hake 55 511 1 Add s x Tc 56 SuLEIs T T Manual Nd ua uds coe a Ec a bc o e c bs 56 Sol TUA Library Add cen xa ul nay kanan ki eens ca ln rci Ue woken a EO e 56 SEZ UI EN ad nk E a ea cea eta NEGRO AIS ee RENE Re aR ee UN 56 Oy Dike dc B E eit crt ove ea ie wl Pa we adh me ate Ea Weak ete ed SE E 56 6 CALCULATIONS x ind dele 2x220 eck we do Car y ERI o des
33. the optimum tilt values As all of the values for all the combinations are maintained in the digiDART the optimize function does not need to be repeated for each possible rise time The optimization can take from 1 to 10 minutes depending on count rate The effect of optimization on the pulse can be seen in InSight mode in MAESTRO Note however that if the settings were close to proper adjustment before starting optimization the pulse shape may not change enough for you to see In this situation you also may not notice a change in the shape of the spectrum peaks The most visible effect of incorrect settings is high or low side peak tailing or poor resolution See Section 4 1 8 for instructions on optimizing the digiDART 61 digiDART Portable HPGe MCA User s Manual 62 7 SPECIFICATIONS 7 1 digiDART Maximum system throughput gt 100 000 cps Coarse Gain Settings 1 to 32 in binary steps 1 2 4 8 16 32 Fine Gain 0 45 to 1 Input Polarity Selectable from digiDART keypad or in MAESTRO System Conversion Gain Computer selectable as 16384 8192 4096 2048 1024 or 512 channels with optional 32768 Preamplifier Support Supports both resistive and TRP preamplifiers Shaping Time Constants e Rise time 0 8 us to 23 us in steps of 0 2 us e Flattop 0 3 us to 2 4 us in steps of 0 1 us Dead Time Correction Extended live time correction according to Gedcke Hale method Accuracy area of reference peak changes lt 3 fr
34. the same procedure and ORTEC will provide a quotation Damage in Transit Shipments should be examined immediately upon receipt for evidence of external or concealed damage The carrier making delivery should be notified immediately of any such damage since the carrier is normally liable for damage in shipment Packing materials waybills and other such documentation should be preserved in order to establish claims After such notification to the carrier please notify ORTEC of the circumstances so that assistance can be provided in making damage claims and in providing replacement equipment if necessary Copyright 2010 Advanced Measurement Technology Inc All rights reserved ORTEC is a registered trademark of Advanced Measurement Technology Inc All other trademarks used herein are the property of their respective owners ADDITIONAL WARRANTY STATEMENT Please note that the digiDART contains no user serviceable parts Breaking the seal on the case voids your warranty The digiDART should be opened only by ORTEC authorized service personnel iii TABLE OF CONTENTS Installation Page 27 Menu Quick Reference Page 116 WARRANTY aM NOCTES ii 1 INTRODUCTION uit nice sta ala sn sik rk we Ra e uta klr y a RO SCARE d IO kn Av d l AE RU 1 1 1 How the digiDART Collects and Stores Spectra WW KK KK KK KK RR KK KK KK KK 2 BDN Live Spectrums ae e anda erste Cac Een HD MHRD MM M MMDMDBDPDprexz jij jji 2 1 1 2 Stor
35. time Real time Live time remaining Real time remaining Battery time remaining Count rate Count rate in ROI Counts SS 0 J I SN QI RU If any parameters are currently selected they will be indicated by a 1 or 2 before the parameter number If you like these settings press MENU ENTER To remove a setting with 1 or 2 press the parameter number To add a setting press the parameter number If no parameters are set the first one selected becomes 1 If one parameter is selected the next one selected becomes the other number The 1 parameter is shown on the left of the display and the 2 is shown on the right As an example for use in later steps select 2 for 1 and 3 for 2 Press MENU ENTER to return to the Main Menu 4 1 5 ADC For HPGe detectors the spectrum size is normally 8K or more channels and for Nal the spectrum size is normally 512 1024 or 2048 channels To set the number of channels or conversion gain press MENU ENTER 6 4 then 1 Now press 6 for a conversion gain of 16384 channels Press 2 and set the LLD to 50 this is in channels Press 3 and set the ULD to 16380 To turn off the gate press 4 and 1 Press 5 to view the settings you just made to verify they are correct Press MENU ENTER 4 times to return to the spectrum display 4 1 6 Amplifier Now you need to set the amplifier to the proper settings First set the polarity for the input to match the output of the detector GEM
36. you establish MDA presets for up to 20 nuclides Data acquisition stops when the MDAs of all of the selected peaks reach their set value The dialog Fig 18 shows the enable disable status of the MDA presets Use the down arrow to see the MDA preset for nuclides 11 to 20 Use the up arrow to return to the first 10 The presets must be set in numerical order beginning with MDA 0 Figure 18 MDA Presets e g MDA 1 must be next ACTIVE ACTIVE ACTIVE ACTIVE DISABLED DISABLED DISABLED DISABLED DISABLED DISABLED SOONOUBRON 8 1B 3 8 E 8 12 B 17 To enter the values for a specific MDA press its number to display the submenu shown in Fig 19 The details of the calculations and the definitions of the coefficients are explained in Section 6 2 Enter MDA Preset User Enter MDA Preset Actual Enter MDA Coefficient Enter Low Channel Enter ROI Length Enter Efficiency Yield Enter Nuclide Name Clear MDA View Settings OONDORON 1 Enter MDA Preset User Enter the value for the preset as dis played by Gamma Figure 19 Set Up an MDA Vision This value Preset is the preset in activity units Bq or LCi It is the MDA Preset Actual divided by the branching ratio and efficiency as described in Section 6 2 The branching ratio efficiency product is entered below GammaVision also stores this product in the digiDART memory The MDA Preset Actual value is also changed when this is
37. 0256100 lt CR gt Zero width is 256 channels highest possible width in Gauss mode C16383108 lt CR gt Zero width is 16383 channels highest possible width in point mode with zero channel set to 8192 SPECTRUM Returns the complete spectrum channel by channel with no pauses and no other characters START seg mask Starts the acquisition of spectral data The optional segment mask is provided for compatibility with other MCBs and may be any value from 0 to 65535 but is ignored by the digiDART Execution Warnings 000004073 lt CR gt No segment selected occurs with other warnings 000005074 lt CR gt The acquisition is already started no changes made 000006075 lt CR gt A preset was exceeded acquisition was not started 000008073 lt CR gt Unit not optimized since initialization 000016076 lt CR gt Amplifier not PZ d since initialization 000032074 lt CR gt High voltage is disabled The actual response record may be a combination of any of the above records depending on the warning conditions For example 000048081 lt CR gt Amplifier not PZ d and high voltage disabled START _ FLAT AUTO Performs Optimization START_OPTI for a single rise time instead of all rise times 110 6 FIRMWARE COMMANDS AND RESPONSES START OPTIMIZE Starts optimization of PZ and flattop correction for all rise times START PZADJUST AUTO Starts the automatic PZ process The automatic PZ is not complete until indicated by the aut
38. 3 Turning the Power On and Off To power up the digiDART press ON OFF It takes 3 5 seconds for the spectrum display to appear If not connected to a PC when you turn the unit on but do not press any other key the digiDART will wait 10 minutes and shut itself off This avoids battery drain from accidental start up To turn off the instrument press ON OFF again The digiDART is set up to avoid accidental power down so you don t stop a spectrum in mid acquisition The display will ask you to confirm shutdown Press 1 to power down or 0 to ignore the shutdown command 3 4 Changing the Battery Swapping batteries is easy Open the battery hatch at the base of the instrument position the palm of your hand under the opening and tap the digiDART s base gently against your palm The battery will dislodge and slide into your hand Press another battery into place and close the hatch 29 digiDART Portable HPGe MCA User s Manual 30 4 USING THE DIGIDART IN FIELD MODE This chapter tells how to configure and operate the digiDART by keypad in field portable mode You can also connect it to a PC and use software such as MAESTRO to set it up and operate it as a benchtop MCA see Chapter 5 and the MAESTRO Software User s Manual You can only store spectra in the digiDART memory with the STORE button on the keypad Spectra acquired with the digiDART attached to a PC must be stored on the PC or its removable drives The InSight Virtual Oscillosc
39. 7 digiDART Portable HPGe MCA User s Manual DISABLE PZ AUTOMATIC Disables the automatic pole zero mode See also ENABLE PZ AUTOMATIC DISABLE PZ NEED Disables the reporting of an error when the digiDART has not been pole zeroed DISABLE REMOTE Disables the recognition of commands on the alternate communication path See also ENABLE REMOTE and SHOW REMOTE DISABLE THRESHOLD AUTOMATIC DISABLE THRESHOLD SAMPLE DISABLE TRIGGER SPECIAL No function in the digiDART These commands have been included for backward compatibility DISABLE ZERO STABILIZATION Stops stabilization of the zero peak while data is being acquired The zero stabilization adjustment is held at its current value until either zero stabilization is reenabled with the ENABLE ZERO STABILIZATION command or reinitialized with the INITIALIZE_ZERO_ STABILIZATION SET ZERO CHANNEL or SET ZERO WIDTH commands See also SHOW ZERO STABILIZATION ENABLE BLRE AUTOMATIC Enables the automatic determination of baseline restorer time constant See also DISABLE BLRE AUTO SHOW BLRE and SET BLRE ENABLE DISPLAY Enables the spectrum display when the digiDART is disconnected from the PC ENABLE GAIN STABILIZATION Enables the stabilization of the gain peak by the previously selected method either Gauss mode or point mode see SET MODE GAUSS and SET MODE POINT See also DISABLE GAIN STABILIZATION SHOW GAIN STABILIZATION and INITIALIZE GAIN STABILIZATION ENABLE GATE ROUTE Includ
40. Attached to a PC or laptop running any version of Microsoft Windows listed in Section the digiDART operates just like any other ORTEC CONNECTIONS 32 MCB and is compatible with all CONNECTIONS 32 products and our CONNECTIONS 32 Programmer s Toolkit A11 B32 It is backward compatible with existing CONNECTIONS 32 custom applications at the general operation control level And because the digiDART is part of our CONNECTIONS 32 architecture its operations can be controlled remotely over a network with the authentication performed at the data source making the digiDART ideal for unattended monitoring applications 1 1 How the digiDART Collects and Stores Spectra The live or current spectrum and all the associated information are stored in high speed spectrum memory The spectrum can then be stored in the stored spectrum memory Both the live spectrum and the stored spectra are retained when power is turned off and when the battery is removed 1 1 1 Live Spectrum The currently acquiring or most recently acquired spectrum is stored here This also holds the presets ROIs calibration and the SOH status This spectrum is lost when CLEAR is pressed or when a stored spectrum is recalled or read by the PC 1 1 2 Stored Spectrum Memory Stored spectrum memory is the storage place for spectral data acquired in the field At the end of a data acquisition simply press the Store button to copy the spectrum and all the information associated with
41. CX Power on off Display menu Back up Zoom out one menu Enter value Figure 1 The digiDART 2 1 1 The Display The digiDART has a 240 x 160 pixel LCD display for viewing data acquisitions in the field as well as viewing and changing most of the MCA settings In certain situations in which the spectrum should not be viewed by the operator the spectrum display can be disabled When the spectrum display is disabled all keypad functions are operational except 5 Peak Info however the digiDART cannot communicate with a PC digiDART Portable HPGe MCA User s Manual The left and right arrow buttons allow you to move the vertical Marker Line by one channel or one pixel The 0 through 6 number keys move the marker quickly through the spectrum The marker channel is used in the following e The status line shows details of the marker channel on the display Peak Info is displayed for the peak ROI containing the marker e The spectrum Zoom in and Zoom out functions expand or contract the spectrum s horizontal axis around the marker position The Status Line at the top of the display can show any two of the following parameters cursor location energy cursor location channel live time real time live time remaining real time remaining battery time remaining count rate count rate in the current ROI selected with the marker and counts in the ROI Selection of these parameters can only be done from the keypad The ROI
42. EU PERRA 57 Gd nhe Nuchde Report soeur dedcp S At or EXE exu T cU ie P praep 57 GI b CA culattolis gt si as din no ex ER De COE UE D o cca Ga dos 34 6 2 MDA Preset Calculation 45202 amd a ere a c ae oe ACERO ES En 59 0 9 Odin SCODIDZADOBS x asc 58 ae heey de Er sb raye wes pups eee on 59 6 4 Zero Stabilization s eap iar ewe Sac KK KK acad x Xen Wd disci Piani kk ceed 60 6 5 Optimiza nOn SK ase deus ThE N N A W y ipd pde een mine mae edet 60 Te SPECIFICATIONS lt Cree EST bre Pd ee CREM LIE ceu xd e RE ea 63 TV SMD IMP m 63 7 1 1 Electrical and Mechanical 2 542 4 E a a EA ER eod e ea 65 T lr Conector oma tuo aes tek Aarsatelov ui ies deep HER E 4 RR HE RE HHHH 66 qu PE PICTCQUASHES oad sud k n wa ruo Ca bende Ava ee hee accion d eae Pob d P adios 66 7 9 Feature MOSECBIS Gace dah Wine we doo tese s Sod va du o Meat vine eh vidua e 66 8 FIRMWARE COMMANDS AND RESPONSES kk kk kk kk kk kk kk kk k 71 Sale CONNBCTIONSS32 Sind E bb e A PLEASE WW ar Bit l ku del oboe 2a 71 S I Command Records d vez en ec alen eke Qa Oca a na a sin le ar eRe eae eh RP 71 8 1 2 Percent Response Records cvs 24 5 kk kk kk KK KK KK KK KK KK KK KK KK KK KK VEN 72 8 1 3 Dollar Response Records MA ep Sees trig KK KK KK KK ate KK KK we KK KK KK KK kk k 74 8 1 4 Command Catalog A kk ered KK RERUM KK KK KK KK KK KK KK KK LR MES 74 95 2 Direct Communication x aee eo aa t RR OR Bee ee RUE E
43. First ROI group starts at channel 1000 and is 50 channels long D0215000150086 lt CR gt First ROI group starts at channel 2150 and is 150 channels long D0000000000072 lt CR gt No ROI groups to report SHOW_ROI MDA Reports the start channel and number of channels used in the MDA preset calculation Example Response D0700000050ccc Calculation is performed on channels 7000 7049 SHOW ROI NUCLIDE PeakNumber Reports the region to use to compute the counts in the activity calculation PeakNumber assumed 0 if not present specifies which of up to 9 0 8 peaks to report Example Response D0083200052092 Region starts at channel 832 and is 52 channels wide SHOW ROI SAMPLE Displays the ROI Sample setting See also SET ROI SAMPLE Responses C00001088 104 6 FIRMWARE COMMANDS AND RESPONSES SHOW ROI UNCERTAINTY Reports the start channel and number of channels used in the uncertainty preset calculation See also SET ROI UNCERTAINTY Response D0700000050ccc Calculation is performed on channels 7000 7049 SHOW SEGMENT Returns the current segment number Always 1 for the digiDART SHOW SHAPE CUSP Returns the current cusp shape factor Always 1 for the digiDART SHOW SHAP FLAT Reports the width of the flattop in us See also SET SHAP FLAT Responses SHAP FLAT 0000000000001 2 SHOW SHAP RISE Displays the rise time setting in us See also SET SHAP RISE Responses SHAP RISE 0000000000003 2 SHOW SHUTDOWN
44. Indicator line at the bottom of the display shows which channels in the spectrum have the ROI bit set The ROIs can be set using the digiDART keypad and menus Section 4 1 12 or from a program such as MAESTRO 2 1 2 Keypad The keypad allows you to use the digiDART without a host PC The following table tells how to use the buttons in spectrum mode menu mode and parameter text entry mode The parameter text entry mode allows you to enter alphanumeric ROI labels and ROI units for the Nuclide Report and spectrum sample IDs All keys are disabled when the digiDART is connected to a PC Button Spectrum Mode Menu Mode Parameter Text Entry Mode in conjunction with and Q Turns the digiDART on and off See Section 3 5 Switches to the Main Menu Returns you to the previous Completes the entry of a menu From the Main parameter value Menu returns you to spectrum mode Turns on the display backlight The backlight remains on for 10 seconds after the last button press then turns off 2 THE DIGIDART Button Spectrum Mode Menu Mode Parameter Text Entry Mode in conjunction with and Q Begins data acquisition No action No action If in View Status menu If in Enter ID retrieves starts acquisition current ID Manually ends data acquisition No action If in View Status No action menu stops acquisition Erases the currently displayed spectrum Jump to spectrum display Backspace erase from the digiDART memory If you
45. ND Amp In Normal amplifier input Inhibit For TRP or gate Battery Power 5 V 8 5 V for DIM Control for HV SMART 1 HPGe detector control USB Universal serial bus for PC communications 12 15V DC External power input 12 V dc 1 25 A center contact positive 7 2 PC Prerequisites The digiDART support software MAESTRO 32 MCA Emulation Software is included operates on any Windows PC that supports the USB interface MAESTRO 32 runs under Windows 2000 Professional SP4 XP Professional SP2 or higher or Vista Ultimate 7 3 Feature Mask Bits The following table describes the feature bits from the SHOW_FEATURES command discussed on page 95 If the feature is supported in the digiDART the bit is set to 1 if the feature is not supported the bit is 0 Meaning Software selectable conversion gain Software selectable coarse gain Software selectable fine gain Gain stabilizer Zero stabilizer PHA mode functions available MCS mode functions available List mode functions available Sample mode functions available Digital Offset e g 920 Software selectable analog offset E p M E Pigs RS N e Bit 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 APPENDIX A FEATURE MASK BITS Meaning HV power supply Enhanced HV SET HV SET SHOW HV POL SHOW HV ACT Software selectable HV range ENA NAL DIS NAI Auto PZ START PZ AUT
46. O Software selectable manual PZ SET SHOW PZ Battery backed real time clock SHOW DATE TIME SHOW DATE TIME START Sample changer support SET SHOW OUTPUT SHOW INPUT One button acquisition ENA DIS SHOW TRIG SPEC MOVE Nomadic likely to move between opens Local app data SET DATA APP SHOW DATA APP Software retrievable serial number Power management commands Battery status support SHOW STAT BATT Software selectable AMP polarity SET SHOW GAIN POLAR Support for flattop optimization ENA DIS OPTI Stoppable AutoPZ STOP PZ AUTO Network support e g DSPEC Multi drop serial support e g MicroNOMAD Software selectable DPM address SET DPM ADDR Multiple devices e g 919 Software selectable ADC gate mode SET GATE Software downloadable firmware Time histogramming functions available e g 9308 Software selectable lower level discriminator Software selectable upper level discriminator MCS mode SCA input available MCS mode positive TTL input available MCS mode fast negative NIM input available MCS mode discriminator input available Software switchable MCS mode discriminator edge Software programmable MCS mode discriminator level 67 digiDART Portable HPGe MCA User s Manual Bit 42 43 44 45 46 47 48 49 50 51 32 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 68 Meaning Software programmable SCA upper and lower thresholds Software selectable MCS
47. ORTEC digiDART Portable HPGe MCA Operator Manual Printed in U S A ORTEC Part No 783610 0210 Manual Revision F Advanced Measurement Technology Inc a k a ORTEC a subsidiary of AMETEK Inc WARRANTY ORTEC warrants that the items will be delivered free from defects in material or workmanship ORTEC makes no other warranties express or implied and specifically NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ORTEC s exclusive liability is limited to repairing or replacing at ORTEC s option items found by ORTEC to be defective in workmanship or materials within one year from the date of delivery ORTEC s liability on any claim of any kind including negligence loss or damages arising out of connected with or from the performance or breach thereof or from the manufacture sale delivery resale repair or use of any item or services covered by this agreement or purchase order shall in no case exceed the price allocable to the item or service furnished or any part thereof that gives rise to the claim In the event ORTEC fails to manufacture or deliver items called for in this agreement or purchase order ORTEC s exclusive liability and buyer s exclusive remedy shall be release of the buyer from the obligation to pay the purchase price In no event shall ORTEC be liable for special or consequential damages Quality Control Before being approved for shipment each ORTEC instrument must pass a stringen
48. OW NUCLIDE UNITS Reports the nuclide activity units in a F record SHOW OVERFLOW PRESET Reports the state of the overflow preset Responses IT lt CR gt Overflow preset enabled IF CR Overflow preset disabled SHOW PEAK This command returns the contents of the ROI channel with the largest number of counts An ROI channel is a channel that has the ROI flag set The maximum possible value is 2147483647 which 1s the maximum number of counts that can be stored in a 31 bit channel 102 6 FIRMWARE COMMANDS AND RESPONSES Responses G0000000000075 CR Maximum count in an ROI channel is zero or no ROI channels were found G0000000001076 lt CR gt Maximum count in an ROI channel is 1 G2147483646120 lt CR gt Maximum count in an ROI channel is 2147483646 G2147483647121 lt CR gt Maximum count in an ROI channel is 2147483647 SHOW PEAK CHANNEL This command returns the number of the ROI channel with the largest number of counts An ROI channel is a channel that has the ROI flag set The lowest number ROI channel with the largest count is reported if more that one channel contains the largest number of counts Channel 16383 is the highest numbered channel in any device Responses C00000087 CR Maximum count was found in channel 0 or no ROI channels were found see errors below C00001088 lt CR gt Maximum count was found in channel 1 C16382107 lt CR gt Maximum count was found in channel 16382 C16383108 lt CR
49. Presets MDA Preset Amplifier Amplifier2 ADC Nuclide Report 5 USING THE DIGIDART WITH MAESTRO The shutdown can be ORTEC TTL or SMART The ORTEC mode is used for all ORTEC detectors except SMART 1 detectors use the SMART option for those detectors Check with the detector manufacturer for other detectors The TTL mode is used for most non ORTEC detectors The high voltage in the digiDART is supplied by the SMART 1 module or in a separate DIM The recommended HV for SMART 1 is displayed on the dialog For other detectors see the detector manual or data sheet for the correct voltage The polarity is determined by the DIM or SMART 1 module 5 6 Field Data Tab This tab Fig 37 is used to view the digiDART spectra collected in Amplifier Amplfier2 ADC Stabiizer HighVolage Field Mode that is in remote mode Field Data About Status Presets MDA Preset Nuclide Report detached from a PC The digiDART j j Move Spectra is always in Field Mode when discon j o a nected from the PC The spectrum can then be viewed as the active spec Mwe trum in the digiDART The active spectrum is the spectrum where the new data are collected The current active spectrum is lost 3 Stored Spectra 123657 The lower left of the tab shows the total number of spectra not counting Figure 37 Field Data Tab the active spectrum stored in the digiDART memory The spectrum ID of the acti
50. ROR CUR Beo CREER kk ORO 112 INDEX PC LP TCI Ee EAI OO EEE DUG Gees 113 1 INTRODUCTION The ORTEC digiDART is a low power hand held HPGe grade MCA based on low power digital signal processing DSP technology It is ideal for In situ gamma spectroscopy Fissile material assay Chemical weapons assay PINS Comprehensive nuclear test ban treaty activities inspection systems Non fissile waste assay Lighter in weight and more rugged than any previous portable MCA the digiDART gives you a full suite of features for in field data acquisition The display shows the spectra you are collecting in the field in live time without using a laptop With the keypad you can view or change any of the data acquisition settings and internal parameters whenever you need to without a PC The digiDART can perform real time identifications and activity calculations for up to 9 user defined nuclides at a time Everything is user controlled the library for analysis displayed peak labels unit labels calibration parameters regions of interest ROIs and data acquisition settings These can all be downloaded from MAESTRO 32 to the digiDART or you can set them up from the instrument s keypad You can also adjust parameters such as gain and pole zero whenever needed without a PC Spectra can be saved and later uploaded to a PC and reanalyzed in more detail using a more sophisticated analysis package such as our GammaVision 32 MCA Emulation a
51. SET Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_ULD value This sets the upper level discriminator to value in channels SET_UNCERTAINTY_PRESET percent Sets the uncertainty preset to the specified value in percent percent is a floating point value from 0 99 9999 See also SHOW UNCERTAINTY PRESET SET WINDOW start length Sets the window of interest to the specified start channel and number of channels The channels of spectral data in the window of interest are affected by commands such as CLEAR SET DATA and WRITE If neither start nor length is provided the window is set to the maximum size allowed by the conversion gain specified The window of interest is always set to the maximum size after a SET DEVICE command or a SET SEGMENT command Execution Errors 131128085 lt CR gt The start channel was higher than the conversion gain 131129086 lt CR gt The length specified one or more channels that were too high conversion gain 131132080 lt CR gt The start channel was specified without a length If one value is given the other must also be given SET_ZERO_ADJUSTMENT value Sets the zero stabilization adjustment to an arbitrary value from 65535 to 65535 The total range of the adjustment value represents 256 channels This adjustment is usually only made by the gain stabilizer and reset to O with the INITIALIZE_ZERO_STABILIZA
52. SHOLD NEGATIVE and SET THRESHOLD POSITIVE ENABLE THRESHOLD SAMPLE ENABLE TRIGGER SPECIAL No function included for backward compatibility 79 digiDART Portable HPGe MCA User s Manual ENABLE ZERO STABILIZATION Enables the stabilization of the zero peak by the previously selected method either Gauss mode or point mode see SET MODE GAUSS and SET MODE POINT See also DISABLE ZERO STABILIZATION SHOW ZERO STABILIZATION and INITIALIZE ZERO STABILIZATION INITIALIZE Returns the digiDART to the factory default settings Execution Errors The INITIALIZE command simulates a power down power up cycle for the MCB after a simulated loss of battery backed up memory Response 003000072 lt CR gt MCB Power up occurred Memory lost No selftest errors Normal Response for INITIALIZE command INITIALIZE_GAIN_STABILIZATION Resets the gain peak stabilization adjustment to unity no adjustment This value is reported as 2048 by the SHOW_GAIN_ADJUSTMENT command See also SET_GAIN_ADJUSTMENT ENABLE_GAIN_ STABILIZATION and DISABLE_GAIN_STABILIZATION INITIALIZE_ZERO_STABILIZATION Resets the zero peak stabilization adjustment to unity no adjustment This value is reported as 2048 by the SHOW_ZERO_ADJUSTMENT command See also SET_ZERO_ADJUSTMENT ENABLE_ZERO_STABILIZATION and DISABLE_ZERO_STABILIZATION LIST_BLRE Lists the valid settings of the baseline restore function LIST_CORR_FLAT Lists the valid settings of the flattop width
53. TION command See also SHOW ZERO ADJUSTMENT SET ZERO CHANNEL chan Sets the center channel for the stabilizer zero peak If a zero channel is chosen such that the beginning channel or ending channel would be below channel 0 or above the maximum channel as determined by the conversion gain the zero peak width is reduced until the peak fits the device boundaries A zero channel and width must be set before zero stabilization can be enabled See also ENABLE ZERO STABILIZATION 91 digiDART Portable HPGe MCA User s Manual Execution Errors 70131128085 CR The specified channel number would create a peak that was less than the minimum width 3 channels or would be outside the device s range 131136084 lt CR gt The command was attempted while zero stabilization was enabled SET_ZERO_WIDTH chans Sets the width in channels for the stabilizer zero peak The zero width must be chosen such that the beginning channel is no lower than channel 0 and the ending channel is no higher than the maximum channel as determined by the conversion gain The zero channel and width must be set before zero stabilization can be enabled The absolute minimum width for the zero peak is 3 channels and the absolute maximum width for the zero peak is 256 channels in Gauss mode In point mode there is no maximum peak width though the chosen width must allow the peak to fit within the device s channel limits as stated above Execution Errors 131128085 l
54. When the voltage is enabled Figure 10 HV Settings disabled a message is displayed until you press MENU ENTER 2 Set Bias Voltage This sets the HV to the desired voltage The polarity is determined by the SMART 1 or DIM The recommended voltage is shown for the SMART 1 3 Set Shutdown When connecting to a SMART 1 HPGe Detector select 3 For using non SMART 1 detectors choose 1 TTL or 2 ORTEC Fig 11 TTL 2 ORTEC 3 SMART Figure 11 Set Shutdown 13 digiDART Portable HPGe MCA User s Manual 4 View Current HV This displays the current HV parameters as shown in Fig 12 The Type can be GE POS GE NEG or Nal 5 View HV SOH This displays the HV and other state of health flags as shown in Fig 13 2 2 6 2 Amplifier Settings These settings Fig 14 should be performed in this order 9 8 6 3 4 1 2 7 The Device Busy message means the unit is collecting data to continue changing the amplifier settings return to spectrum mode and press STOP 1 Coarse Gain This sets the amplifier coarse gain to x1 x2 x4 x8 x16 or x32 2 Fine Gain HV Status HV Target Bias HV Actual Bias HV Shutdown pe Ty Overloaded Status HV Serial SMART 1 Detector Recommend HV Live Det Temp Figure 12 View Current HV Settings 24V 12V 12V 24V Tem HV Volt Shutdown Overload Security Power Figure 13 Monitor the SOH Flags 1 Coarse Gain 2 Fine Gain 3 Rise
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56. a single zero 0 as the password is the remove password command After assigning the password s power the digiDART off on to ensure they are in effect If the user password is set the digiDART will prompt for the password when the unit is started up If both a user and administrator password have been activated either the user password or the administrator password can be entered at startup If you enter it correctly the password screen closes and the digiDART goes to spectrum mode unless the spectrum is locked and you have only user access If not correct an Access denied message is displayed If the spectrum is locked a text message will be shown at startup to indicate that the password was accepted Once the administrator password is set you must enter the administrator password to change passwords To exit the administrator level cycle the power off on Table 3 summarizes how the two passwords work Table 3 digiDART LF Passwords Password s set Required on Required to adjust setup controls startup User pwd only Yes No full access granted User and Admin pwds One of the two If only User pwd entered no access to setup controls If Admin pwd entered full access granted If the user and administrator passwords are identical entering the password grants full administrator access To set or change the user password press MENU ENTER 7 General Settings 1 Change User Password Now enter the number
57. alues Normally the start date and time are set automatically whenever a device is started with the START command See also SHOW DATE START SET TIME START and SHOW TIME START SET DELAY COLLECTION value Controls the pileup rejector by setting a width threshold such that if a fast channel discriminator pulse is wider than value the pulse is rejected This portion of the pileup rejector rejects pulses that are too close together to be detected separately by the fast channel Value is in microseconds with a range from 0 250 to 6 in steps of 0 05 See also SHOW DELAY COLLECTION SET DELAY SAMPLE num Delays the waveform collected in InSight mode by num points Num must be between 0 and 65535 See also SHOW DELAY SAMPLE SET DEVICE SET DISPLAY SET FRONT BYPASS Not used included for backward compatibility SET GAIN ADJUSTMENT value Sets the gain stabilization adjustment to an arbitrary value from 65535 to 65535 This adjustment is usually made only by the gain stabilizer and reset to 0 with the INITIALIZE GAIN STABILIZATION command See also SHOW GAIN ADJUSTMENT Execution Errors 131134082 lt CR gt The command was attempted when the currently selected device was other than device 1 83 digiDART Portable HPGe MCA User s Manual SET GAIN CHANNEL chan Sets the center channel for the stabilizer gain peak If a gain channel is chosen such that the beginning channel or ending channel would be below channel 0 or above the maximum c
58. an just press MENU ENTER to go back without changing anything The Main Menu for the USB digiDART is shown in Fig 2 For the digiDART R s main menu see the digiDART R user s manual supplement View Status Enter ID Nuclide ROIs Status Line Peak Info Adjust Controls General Settings Spectrum Memory Nuclide Report 1 2 3 4 5 6 7 8 9 Figure 2 The Main Menu 2 2 1 1 View Status The status screen Fig 3 displays all of the major Live Time sec MCA settings at one time Press MENU ENTER to Ae MM return to the Main Menu Battery Time Remains Bias Voltage Volts Fine Gain Coarse Gain RiseTime FlatTop BLR Setting Figure 3 View Status 2 2 2 2 Enter ID Allows you to enter an 8 character alphanumeric Enter ID identifier to describe the sample as shown in Fig 4 TEST 001 Current ID is SEALAKE1 Figure 4 Enter Spectrum ID 10 2 THE DIGIDART 2 2 3 3 Nuclide ROIs Use this screen Fig 5 to set up the ROIs for the 1 Nuclide RO 10 SEINE Nuclide Report which is described in Section 6 1 Each 5 Nu BO l ACTIVE ABLED ROI is labeled as ACTIVE the ROI will be displayed on 4 Nuclide ps 3 DEED the Nuclide Report screen or DISABLED the ROI will Ide ROI 5 ACTIVE not be displayed on the report screen To view the real A ARTEL time Nuclide Report for the currently active ROIs press 9 Nuclide ROI 8 DISABLED i 0 View Nuclide Report 0 View Nuclide Report
59. ands 5 Auto Contrast Automatically adjusts display contrast as ambient temperature changes Note that you can also adjust the contrast in menu mode by the up down arrow buttons Enable Auto Contrast 2 Disable Auto Contrast 6 Calibrate Allows you to enter slope and intercept linear calibration coefficients from the keypad This replaces the previous calibration including calibrations from the host PC See Section 4 1 10 for more details This calibration will be read by software when the digiDART is connected to the PC Enter Slope This can be any positive decimal number 2 Enter Intercept This can be any positive or negative decimal number 3 View Current Calibration 7 Display Figure 23 shows the Display menu 1 Adjust Scale Adjust Scale Selects between 3 View gs DE linear and log and autoscale on or autoscale off Autoscale Off applies only to linear displays Figure 23 Adjust Display Settings 23 digiDART Portable HPGe MCA User s Manual 2 Set Display Mode PHA 3 View Settings 2 2 8 8 Spectrum Memory Figure 25 shows the Spectrum Memory menu These 1 Auto Switches the linear vertical scale to autoscale mode which continuously adjusts the vertical scale so the tallest peak on the display is shown at about 75 of the maximum height of the screen Autoscaling continues until you select 3 You can also autoscale by pressing lt 8 Up arrow gt 2 Log Switches to logarithmic vertical sca
60. annel Zero Stab Width Initialize Zero Stab Enable Nal View Current Settings Enable Gain Stabilization This will enable the gain stabilizer to operate The stabilizer must be set up before it can be enabled An error message is displayed if the stabilization cannot be enabled A confirmation message is shown if the stabilizer is enabled Press MENU ENTER to continue 1 2 3 4 5 6 7 8 9 0 Figure 21 Stabilizer Settings 2 Gain Stab Center Channel This is the center channel of the region used for the stabilization The peak will be centered in this region by the stabilizer operation The peak should be in the upper half of the spectrum and isolated from other peaks 3 Gain Stab Width This is the width in channels of the peak region to be used It should be slightly wider than the peak but not overly wide 4 Initialize Gain Stabilization Resets the gain peak stabilization adjustment to unity no adjustment 5 Enable Zero Stabilization This enables the zero stabilizer to operate The stabilizer must be set up before it can be enabled A confirmation message is shown when the stabilizer is enabled an error message is displayed if stabilization cannot be enabled Press MENU ENTER to continue 6 Zero Stab Center Channel This is the center channel of the region used for the stabilization The peak in this region will be centered by the stabilizer operation The peak should be in the lower quarter of the spect
61. anual The Input Polarity radio buttons select the preamplifier input signal Field Data About Status Presets MDA Preset Nuclide Report polarity for the signal from the Amplifier Ampifier2 ADC Stabiize HighVoltage detector Normally GEM p type r Gain 1 87 Baseline Restore Optimize detectors have a positive signal and 0 45 Start Auto GMX n type have a negative signal pon ow i S top Aut Preamplifier Type __Stop Auto The Baseline Restore is used to return the baseline of the pulses to the true zero between incoming pulses This improves the resolution by removing low frequency noise such as dc shifts or mains power ac pickup The base line settings control the time constant Figure 32 Amplifier Tab of the circuit that returns the baseline to zero There are three fixed choices Auto Fast and Slow The fast setting is used for high count rates the slow for low count rates Auto adjusts the time constant as appropriate for the input count rate The settings auto fast or slow are saved in the digiDART even when the power is off The time constant can be manually set on the InSight display see the InSight discussion in the MAESTRO Software User s Manual Fine 0 4672 Resistor Feedback M Input Polarity Coarse B Bb E You can view the time when the baseline restorer is active on the InSight display as a Mark region see the disc
62. ared to the original values If there is a mismatch the Security SOH bit is set 9 Power Set if the power fails during an acquisition 4 1 10 Calibration Now set up a two point linear fit calibration First collect a spectrum or use the one collected above Locate the peaks in the spectrum for the source Use the left or right arrow to scroll the cursor to the first peak Record the cursor channel as shown in the upper left corner of the display Now put the marker on the second peak Now find the slope by dividing the difference between the two energies by the difference between the two channel values This is the slope To enter the slope press MENU ENTER select 7 General Settings 6 Calibrate then 1 now enter the slope To calculate the intercept multiply the slope by the low channel number Subtract this value from the low energy This is the intercept Press 2 and enter the intercept This linear calibration is used in the Peak calculation for the Nuclide Report see Section 6 1 1 For example for a Co spectrum the 1173 peak is in channel 7241 and the 1332 peak is in 8226 This gives 1173 1332 7241 8226 or 0 1614 for the slope and 1173 0 1614 7241 or 4 148 for the zero intercept The zero intercept is the energy of channel 0 in the spectrum 35 digiDART Portable HPGe MCA User s Manual Select 3 to show the current slope and intercept Press MENU ENTER 4 times to show the spectrum NOTE The most
63. as not pole zeroed The command was ignored Device preset already exceeded and high voltage not enabled The command was ignored Device preset already exceeded high voltage not enabled and amplifier was not pole zeroed The command was ignored Power up just occurred and the selftest results are All power up selftest passed Battery backed up data lost Invalid command verb Invalid command noun Invalid command verb and noun Invalid command modifier Invalid command verb and modifier Invalid command noun and modifier Invalid command verb noun and modifier Invalid command verb noun and modifier valid but not together Serial line buffer overrun Serial line parity error Serial line buffer overrun and parity error Serial line framing error Serial line buffer overrun and framing error Serial line parity error and framing error Serial line buffer overrun parity error and framing error Serial line break detected Command checksum incorrect only when optional checksum provided Command or WRITE handshake record too long WRITE command aborted by HA handshake 73 digiDART Portable HPGe MCA User s Manual 20130132079 CR WRITE command aborted by timeout 130133080 lt CR gt WRITE command aborted by invalid handshake Execution Errors 131128085 lt CR gt Invalid 1st command parameter 131129086 lt CR gt Invalid 2nd command parameter 131130078 lt CR gt Invalid 3rd command
64. avigator III The efficiency can be calculated by a program such as ScintiVision or determined by other methods To confirm that you have entered the desired values and labels press 7 to show the current setup for this ROI Press MENU ENTER to return to the setup list 11 digiDART Portable HPGe MCA User s Manual When setup is complete press MENU ENTER to return to the Nuclide Report list of ROIs The ROIs you have set up will now be marked ACTIVE To enter another region press the number and repeat entry as described above To remove an ROI from the report press the corresponding Nuclide ROI number to open the setup list then press 6 Clear ROI This will completely remove all the setup information for this one ROI which will now be marked DISABLED on the Nuclide ROIs screen The Nuclide Report will display the active ROIs in the order entered on this setup screen Note that these ROIs are separate from the spectrum ROIs discussed in Section 4 1 12 and are not displayed or marked in any way on the spectrum screen 2 2 4 4 Status Line The Status Line at the top of the spectrum display can 1 1 Cursor Location Energy show any two of the parameters shown in Fig 7 2 in Av Channel Real Time Live Time Remaining The numbers are select deselect toggles i e press a number once to select an item and press again to de select it When you mark the first status item a 1 appears beside your first selection Th
65. c bat and ini83905 exe to make room for ROMDISK ABS It also stops all acquisitions which are in progress See WRITE_FILE_FLASH and CLOSE_FILE_FLASH Not normally used 81 digiDART Portable HPGe MCA User s Manual RESET Resets the digiDART to the state just after power is applied This command responds with a response that indicates power up just occurred RESET REMOTE Resets any UART error conditions when sent to the digiDART via the Ethernet SAMPLE Sending this command causes another waveform to be captured in InSight mode This command is invalid when not in InSight mode Execution Errors 131136084 lt CR gt Command not allowed in current mode of operation SET_BLRE baseline This sets the baseline restorer time constant to the value baseline Baseline is in microseconds with a range from 10 to 100 The specified value is only used if automatic baseline restorer mode is disabled See also ENABLE_BLRE DISABLE_BLRE and SHOW_BLRE Execution Warnings 000064079 lt CR gt Value was rounded to the closest legal value SET CONFIGURATION UART bbbbbpds Sets the baud rate parity number of data bits and the number of stop bits for serial port communication The parameter is an ASCII string which specifies the settings where bbbbb is the baud rate with leading zeros if necessary p is replaced with O E or N to indicate odd even or no parity d is replaced with the number of data bits 5 8 and s is replaced with the numbe
66. channels This command can be used multiple times to set ROI flags without affecting previously set flags ROI flags specify channels within a device that are considered for ROI integral and ROI peak presets SET ROI MDA start numchans PeakNumber Sets the region to use to compute the gross counts in the MDA calculation PeakNumber is an optional parameter assumed 0 if not present that specifies which of up to 20 0 19 MDA Presets to change SET ROI NUCLIDE start numchans PeakNumber Sets the region to use to compute the net counts in the activity calculation PeakNumber is an optional parameter assumed 0 if not present that specifies which of up to 9 0 8 peaks to change SET ROI SAMPLE num Selects which controls signals are displayed as an ROI on the captured waveform Only a single bit can be turned on at a time The following signals can be selected with the associated bit Bit 0 Pileup reject Bit 1 Negative baseline threshold Bit 2 Baseline restorer gate 88 8 FIRMWARE COMMANDS AND RESPONSES Bit 3 Positive baseline threshold Bit 4 Busy Bit 5 Gate Bit 6 Reserved Bit 7 Peak detect Bit 8 Reserved SET ROI UNCERTAINTY start chans Sets the region to be used for the uncertainty preset calculation See also SHOW ROI UNCERTAINTY SET SEGMENT SET SHAPE CUSP Not used included for backward compatibility SET SHAP FLAT value Sets the width of the flattop to value Value is in microseconds rang
67. cients a b and c used for the MDA calculation See SET MDA COEF Example Responses MDA COEF 000000000002 71 000000000000000 00000021 700001 Coefficient a 2 71 b 0 and c 21 7 SHOW MDA PRESET PeakNumber Reports MDA preset PeakNumber If PeakNumber is omitted 0 is assumed Example Response MDA PRES 0000000000025 7 100 6 FIRMWARE COMMANDS AND RESPONSES SHOW MODE Reports the current mode of operation PHA or Sample InSight Virtual Oscilloscope See also SET MODE PHA and SET MODE SAMPLE Responses FPHA lt CR gt PHA mode FSAM lt CR gt Sample mode InSight SHOW_MODE_STABILIZATION Reports the current stabilization mode of operation See also SET MODE POINT and SET MODE GAUSS Responses FPOINT lt CR gt FGAUSS lt CR gt SHOW_MODE_TEST Reports whether the digiDART is in test mode and if in test mode which test mode is it in This command is normally only used for testing at the factory Responses A000ccc Not in test mode A001ccc ADC test mode SHOW MONI LABEL num Returns with an ASCII string label designation for the monitor num SHOW MONI MAX Returns with the number of monitors available for viewing SHOW MONI VALUE num Returns with an ASCII representation of the value for the monitor SHOW NAI Indicates whether ENABLE NAI has been sent Responses are true and false Responses IT lt CR gt Nal mode enabled IF lt CR gt Nal mode disabled SHOW_NEXT Used in conjunction with th
68. communication with the digiDART is not as simple and straight forward as the ASCII syntax However there are some situations where it is necessary to use direct communication The direct syntax is explained in Section 8 2 8 1 CONNECTIONS 32 In CONNECTIONS 32 the communication consists of sending command records to the MCB API and receiving response records from the MCB API Both command and response records consist of a sequence of printable ASCII characters followed by an ASCII carriage return The single exception to this rule is the B response record for the WRITE command which contains binary integer numbers All commands eventually respond with a percent response record so named because the response begins with an ASCII percent sign 96 which signifies the completion of the command SHOW and STEP commands respond with a dollar response record which begins with an ASCII dollar sign followed by a percent response record The WRITE command can respond with multiple pound sign records which begin with an ASCII pound sign but eventually completes by sending a percent response record All other commands result in a single percent response record upon completion 8 1 1 Command Records Commands consist of a command header that may be followed by numeric parameter values The header consists of a verb or a verb and noun separated by an underscore or a verb noun and modifier each separated by underscores The verbs
69. ctrum WARNING memory You must confirm the deletion of the This operation will completely spectra The display is shown in Fig 27 a shucue Are you sure you want to continue 1 YES 0 NO Figure 27 Erase All Stored Spectra be careful 3 Spectrum Directory Allows you to see the list of spectra in the stored spectrum memory Fig 28 The format is EGAN DOE MSIE 2 HILL 003 06 28 16 37 37 a 3 HILL 004 06 28 17 12 29 sequence spectrum id month day hour minute second 4 HILL 005 06 28 17 45 15 5 CREEK 1 10 18 09 11 45 6 CREEK 2 10 18 09 22 00 The bottom of the screen displays a message CHEERS 1013 0934 saying x of yit bytes used so you can keep track 988260 of 1638400 bytes used of the storage remaining Use the up and down arrows to go through the spectra one page at a Figure 28 Monitor Stored time Also you can advance to a particular spec Spectra trum by entering its sequence number or spectrum ID so you don t have to go through the list 25 digiDART Portable HPGe MCA User s Manual 2 2 9 9 Nuclide Report The Nuclide Report Fig 29 is a very useful tool for n s Nuclide uCi m2 monitoring nuclide count rates and activities in the field CO 60 121 E01 The report readouts update in real time for as long as the 1 48E00 report screen is displayed so you can have a live reading of the selected nuclides You can select up to 9 gamma ray energies located anywhere in the spect
70. ctrum The stabilization operates by keeping a peak centered in an ROI you have defined The ROI should be made symmetrically about the center of a peak with reasonably good count rate in the higher channels of the spectrum The ROI should be about twice the FWHM of the peak If the region is too large counts not in the peak will have an effect on the stabilization 59 digiDART Portable HPGe MCA User s Manual Before setting either stabilization peak the coarse and fine gains should be set to the desired values and the pole zero performed 6 4 Zero Stabilization The zero stabilizer Section 2 2 6 5 enables you to control the zero level or offset stabilizer The zero level stabilizer uses a peak in the spectrum to monitor the changes in the zero level of the system amplifier The zero stabilizer controls the offset bias level so the peak will be maintained in its original position The input pulse height to channel number relationship is Channel number Intercept Gain pulse height where Intercept The channel number of the zero height input pulse Gain The relation between pulse height and channel number slope of the curve Changes in either the zero intercept or gain can affect the positions of all the peaks in the spectrum When used with the gain stabilizer both the zero intercept and the gain slope are monitored to keep all the peaks in the spectrum stabilized The zero stabilization and gain stabilization are separa
71. d Only TIPS hela cua 09 2001 ricci means it is locked Firmware Revision Serial Number Acquisition Mode DDAR 002 P23 PHA Figure 38 About Tab 5 8 Status Tab Figure 39 shows the hardware Status tab Twenty one parameters are monitored at all times Use the droplists to select any six parameters to be displayed simultaneously on the this tab You can change your selections at any time Two types of status responses are displayed OK or ERR and a numeric value The state of health SOH parameters all respond with OK or ERR If the state is OK the parameter stayed within the set limits during the spectrum acquisition If the parameter varied from the nominal value by more than the allowed limit the ERR is set until cleared by the program The numeric values are displayed in the units reported by the digiDART The Security Temperature State of Health Detector temperature and Live detector temperature readouts are not available for this unit and read N A 50 5 USING THE DIGIDART WITH MAESTRO The parameters are Amplifier Amplifier2 ADC Stabilizer HighVoltage Detector State of Health Field Data About Status Presets MDA Preset Nuclide Report This is OK if all the SOH are OK SEMUIDET eae aE Jetector State Uf Health aecurity Yerihication Error and ERR if any one is ERR a 2 DIM 24 State Of Health DK DIM 24V State of Health DIM 12V State OfHeath w OK This is OK if
72. d pause the page with spectrum 3 at the top will be displayed Next press 5 and pause now the page with spectrum 35 at the top will be displayed Now press 1 to show the page with spectrum 351 at the top 40 4 USING THE DIGIDART IN FIELD MODE To browse through all the spectra use the down arrow key to display the next group of 8 spectra and the up arrow key to display the previous group of 8 4 1 19 Downloading Spectra to the PC After you have collected the spectra and stored them in the digiDART stored spectrum memory you can download them to a PC disk storage The download of the spectra is controlled by PC based software such as MAESTRO Typically the software allows you to download the spectra one at a time or all at one time automatically See the software user s manual for details on downloading and saving the spectra When connected to the PC the digiDART displays a USB Connected message Otherwise the display and keypad are disabled Every function is available to the software dialogs except the ability to store spectra enter or change the digiDART user and administrator passwords and display locking MAESTRO GammavVision and other ORTEC programs have detector locking commands that prevent unauthorized users from changing detector settings starting and stopping data acquisition and clearing the detector memory These commands function separately from the digiDART s user and administrator passwords If the
73. digiDART is locked by software it can be used in the field without knowing the password but cannot be reconnected to a PC and its memory erased unless the user knows the password 4 2 Should You Take a Laptop Into the Field The digiDART is designed so that you don t need a PC to operate it especially in the field But there are a few situations where a laptop is of use in field operations One use is for advanced analysis of the spectra where the Nuclide Report does not show enough detail In this case software such as GammaVision or M 1 can be used to process the spectra on the spot The second is to provide storage for more spectra than the digiDART stored spectrum memory capacity see Table 1 page 3 A laptop with MAESTRO will allow you to periodically transfer spectra from the digiDART and clear its spectrum memory so you can continue data collection 4 2 1 Operation with a PC The details of the operation of the digiDART by the PC software depend on the software itself ORTEC software such as MAESTRO is described in the manual for the software In general the digiDART operates very much like other ORTEC MCBs using CONNECTIONS 32 The digiDART is a modern digital signal processor with all the settings controls and adjustments controllable by software To use it with your own software we recommend using the CONNECTIONS 32 Programmer s Toolkit with Microsoft ActiveX Controls A11 B32 The commands are given in Chapter 8 For
74. digiDART will not communicate with PC based spectroscopy applications To restore communication with the PC software you must unplug the USB cable enter the administrator password unlock the display then reconnect the USB cable 4 1 18 Collecting Spectra You are now ready to collect spectra When you have collected the first spectrum it can be saved in the digiDART s internal stored spectrum memory To save the spectrum press STORE enter the 8 character spectrum ID to be stored with the spectrum then press MENU ENTER The current ID is displayed To use this just press MENU ENTER The same ID can be used in multiple spectra On the ID entry dialog you are also shown the amount of memory used and the amount used for this spectrum When the memory is full a warning is displayed The next dialog asks you to confirm that you want to store this spectrum Press 1 to store or 2 to skip the storage process An individual spectrum cannot be erased from the stored spectrum memory The list of stored spectra is shown from the spectrum display by pressing MENU ENTER 8 3 The list is shown by sequence number ID and date time To show any particular spectrum enter the sequence number For sequence numbers above 9 enter the first digit then the second digit then the other digits Depending on how quickly you enter the two or more digits the display may update with different lists For example to select spectrum 351 Press 3 an
75. dministrator locks the spectrum display the spectrum screen shows a locked message and the 5 Peak Info function is not available However the operator can still view the Nuclide Report To lock the display enter the administrator password then go to the Main Menu press 7 General Settings 4 Lock Spectral Display then 1 LOCK The Display Locked message will be displayed Press MENU ENTER 2 times to return to the General Settings menu Now power off the digiDART On next startup the display will be locked and can only be unlocked by an administrator To unlock the display in administrator mode go to the Main Menu press 7 General Settings 4 Lock Spectral Display then 1 UNLOCK The Display Unlocked message will be displayed Press MENU ENTER 2 times to return to the General Settings menu Table 4 summarizes how passwording interacts with spectrum locking 39 digiDART Portable HPGe MCA User s Manual Table 4 Passwords and Spectrum Locking Spectrum locked effect is Spectrum displayed immediate if admin pwd set Yes Only User pwd set Yes Only Admin pwd set No must enter Admin pwd to display spectrum Both User and Admin pwds set If only User pwd entered spectrum not displayed If Admin pwd entered spectrum displayed If the user and administrator passwords are identical entering the password grants full administrator access and spectrum is displayed NOTE When the display is locked the
76. e unnecessary width increases the background and the MDA value This is the number of channels for the peak region The region should be wide enough to end in the background above the peak The three right most channels should be background The region should not be wider than necessary as the unnecessary width increases the background and the MDA value Enter the product of the detector efficiency and the gamma ray yield or branching ratio This value is entered by GammaVision when you use it to setup the Preset To retain the current value press MENU ENTER MDA Preset Actual Efficiency Yield product x MDA Preset User Enter the nuclide name to be displayed in the MDA table and in the software display This is loaded by the software when the preset is set to retain the current name press MENU ENTER This disables the current MDA and sets all of the settings to 0 except the coefficients 19 digiDART Portable HPGe MCA User s Manual 9 View Settings This shows the 6 values entered above as well as the current MDA calculation for the peak region 7 View Current Settings This displays the live time real time ROI integral and ROI peak presets currently being used The uncertainty and MDA presets have separate displays 2 2 6 4 ADC Settings The dialog is shown in Fig 20 Conversion Gain LLD a ULD 1 Conversion Gain Gate This is the ADC conversion gain It is the number Se caer nee of channels in th
77. e SHOW ROI command SHOW NEXT reports the next continuous group of channels that have the ROI flag set The response is of the form Dsssssnnnnnccc CR 101 digiDART Portable HPGe MCA User s Manual where sssss represents an integer number that is the number of the first channel of the next group of channels that all have their ROI bit set and nnnnn represents an integer number that is the number of channels in the group If no more channels have their ROI bit set SHOW NEXT returns a first channel of 0 and a number of channels of 0 The SHOW ROI command is used to report the first group of channels that all have their ROI bit set Example Responses D0100000050078 CR Next ROI group starts at channel 1000 and is 50 channels long D0215000150086 CR Next ROI group starts at channel 2150 and is 150 channels long D0000000000072 CR No other ROI groups to report SHOW NUCLIDE PeakNumber Reports current activity and uncertainty for the nuclide selected by PeakNumber PeakNumber is assumed to be 0 if not supplied Example NUCLIDE 0000000000010 7 0000000000001 2 Activity is 10 7 and uncertainty is 1 2 SHOW_NUCLIDE_COEFFICIENT PeakNumber Reports the coefficient for a specific peak as a floating point number that corresponds to the number set with SET NUCLIDE COEF Example NUCLIDE COEF 0000000000010 7 SHOW NUCLIDE DESC PeakNumber Reports the nuclide label for the specified peak in a F record SH
78. e digiDART is cycled through all the rise time values for the determination of the optimum tilt values As all of the values for all the combinations are maintained in the digiDART the optimize function does not need to be repeated for each possible rise time The optimization can take from 1 to 10 minutes depending on count rate You should repeat the optimization if the flattop width is changed The effect of optimization on the pulse can be seen in the InSight mode on the Amplifier 2 tab Note however that if the settings were close to proper adjustment before starting optimization the pulse shape might not change enough for you to see In this situation you also might not notice a change in the shape of the spectrum peaks The most visible effect of incorrect settings is high or low side peak tailing or poor resolution 5 2 Amplifier 2 Tab Figure 33 shows the Amplifier 2 Properties LX tab which aEDESSES the advanced Field Data About Status Presets MDA Preset Nuclide Report digiDART shaping controls Amplifier Amplfier2 apc Stabilizer High Veltage including the InSight Virtual Oscil Eg l d hich is discussed ER gi Md id odd 200 2J Width pon 4 in the MAESTRO Software User s Maus Tilt 0 03306 m Pole Zero The many choices of Rise Time InSight allow you to precisely control the Start _Stop tradeoff between resolution and throughput The MAESTRO manual
79. e numeric value Lower case letters enclosed in quotes represent alphanumeric character strings rather than numerical values Items in the command prototype that are surrounded by square brackets are optional items and are not always required In this section the term CR represents the ASCII carriage return character decimal value 13 and the character represents the ASCII underscore character decimal value 95 CLEAR The channels of spectral data in the window of interest see SET WINDOW command are set to zero The live time and true time counters are also set to zero This command is equivalent to the combination of CLEAR COUNTERS and CLEAR DATA commands CLEAR ALL This command is equivalent to the combination of CLEAR COUNTERS CLEAR DATA CLEAR PRESETS and CLEAR ROI commands Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken CLEAR_COUNTERS The live time and true time counters are set to zero CLEAR_DATA The channels of spectral data in the window of interest see SET WINDOW command are set to zero The ROI flags are not changed nor are the presets changed CLEAR HV HEALTH Clears resets the state of health bits 75 digiDART Portable HPGe MCA User s Manual CLEAR MDA PRESET Clears all MCA preset values This command is used to quickly clear the list of MDA preset values CLEAR NUCLIDE PeakNumber Clears all param
80. e spectrum Select from 512 1024 2048 4096 8192 16384 and optional 32768 Press MENU ENTER to keep the current setting Figure 20 ADC Settings 2 LLD This is the lower level discriminator It should be set to reject any low level noise but not any useful peaks 3 ULD This is the upper level discriminator It is normally set to the conversion gain value It is automatically set to the last channel when the conversion gain is changed 4 Gate 1 Off This is the normal mode of the gate input 2 Coincidence This sets the gate mode to coincidence mode In this mode only those counts that are in coincidence with the gate are counted in the spectrum To inspect the relative timing for the two pulses connect to a PC and use the InSight Virtual Oscilloscope mode in MAESTRO 3 Anticoincidence This sets the gate mode to anticoincidence mode In this mode only those counts that are not in coin cidence with the gate are counted in the spectrum Use the InSight mode in MAESTRO to inspect the relative timing for the two pulses 20 2 THE DIGIDART 5 View Current Settings This displays the ADC settings currently being used 2 2 6 5 Stabilizer Settings The dialog is shown in Fig 21 Gain and zero stabilization are discussed in detail in Sections 6 3 and 6 4 respectively Enable Gain Stabilization Gain Stab Center Channel Gain Stab Width Initialize Gain Stab Enable Zero Stabilization Zero Stab Center Ch
81. e test the argument against the list of valid settings and return true if valid WRITE SPECTRUM Directs the digiDART to write the current active spectrum into stored spectrum memory Same function as the STORE button 8 2 Direct Communication The direct communication is a compact direct method of control It is used through the USB or optional RS232 port This method is simpler for small hand held controllers and easier to implement in operating systems such as DOS Not all commands available in CONNECTIONS 32 are available in the direct method This method of communication is only appropriate in very specialized applications where you wish to connect the digiDART to a computer that does not use the Windows operating system or does not support the USB interface Contact ORTEC for details on the commands 112 Acquiring spectra 3 5 2m edet e iR 40 ADC Sep 52 s Sashes d eyes DSS es Gules 20 46 view status line parameters 33 Adjust Controls menu 000 13 Amplifier settings 14 33 43 Backlight n n sura bbs ESSO E 6 Baseline TESIOFGE ces va s si ca dk elb ak ee ES 44 Batey si awa an Gaye Wa Ebata E Pant as 29 31 65 DIAS ab cae etade d bd We d aki eu e ey 48 Cabline cos ste ne ae a ah Gan ben 28 Calibrale x2 saa Rb wa dabi Guran 23 35 CONVERSION PAID Al y ra a SA PR ENS 20 Discrimi dtors 33v eda E es hex 20 Display acts oet Cubes ER C een 5 Disp
82. ecessary to do the pole zero step as this is done automatically during optimize Press MENU ENTER 3 times to return to the spectrum display 4 1 9 Detector State of Health Press STOP Now you can view the SMART 1 HPGe Detector state of health to check what has happened during the last acquisition To check the detector SOH press MENU ENTER 6 1 5 View HV SOH This will display the status of the nine SOH bits as shown in Table 2 The Values are cleared on each START and set on each STOP Press MENU ENTER 4 times to return to the spectrum display 34 4 USING THE DIGIDART IN FIELD MODE Table 2 State of Health Bit Definitions of mw The first four bits monitor the voltages coming from the digiDART If one of these ERE a values varies by 2 V the corresponding bit is set EUM Temperature Set if the detector temperature increases and shuts down the HV therefore the SHUT bit will also be set 5 HV voltage Set if the high voltage deviates 300 V from the value you entered in 6 Adjust Controls 2 Set Bias Voltage 6 Overload Set if the preamplifier overloads for more than about 4 0 seconds Set if the preamplifier shuts down for any reason Security At the start of the acquisition the digiDART queries the Smart 1 HPGe Detector for its serial number The digiDART then writes a random number to the Smart 1 HPGe Detector At the end of the acquisition both numbers are read from the Smart 1 HPGe Detector and comp
83. ectrum memory The display format is sequence spectrum id start date start time The bottom of the screen displays a message saying x of yit bytes used so you can keep track of the available storage Use the up and down arrows to scroll through the spectra if there are too many to view at once on the screen Also you can advance to a particular spectrum by entering its sequence number or spectrum ID so you don t have to scroll through the list If you try to store a spectrum when the spectrum memory is full the digiDART displays a Write Error Spectrum Memory is Full message digiDART Portable HPGe MCA User s Manual 1 2 Host PC and Software Requirements The digiDART can be operated with any suitable version of ORTEC software including MAESTRO 32 MCA Emulation Software version 5 2 or higher The digiDART is supported on any Microsoft Windows PC that supports the USB port The current release of MAESTRO 32 runs under Windows 2000 Professional SP4 XP Professional SP2 or higher and Vista Ultimate 2 THE DIGIDART 2 1 Display and Keypad Figure 1 shows the digiDART s display and keypad and highlights some of its features ORTEC digiDART Li 1490 keV 1000 sec I Status line Marker line cursor Arrow keys Q Left minus ROI Right decimal pt indicators Taller Contrast Shorter Contrast LCD display backlight Enter values Jump through spectrum Spectrum e acquisition j controls
84. ed Spectrum Memory kk kk kk kk kk kK KK KK KK KK KK KK KK KK kk kk kk k 2 1 2 Host PC and Software Requirements icd e b E KK KK KK KK KK KK KK KK KK KK KK KK KK 4 2 THE DIGIDARE a 1nd n Puce abr d wi ee Eb a ebbe daba tes 5 2 1 Display and Keypad dece kk kk kk KK KK KK UR KK KK KK KK KK KK KK kk kK kk kk k 5 UN NUN UICEP TERRE 5 Dell Pe USC VB ceni qat onis dnt as Sec ts r bur hubs ad tax dedi Gas Pete eee Peas c aia quA 6 2 2 Men Commands sro exe video bei exo nba ev ed ehhh bi e tog 9 DO At VIGWSS aS sy oleate se C i ipiis eoi RE e DE e a bt ahah ah hey tude 10 2220 BBtectus ao f iiec Ay ed E ND AS Ted eda taque pd 10 2525959 Nucleo ROI 223an 5 222 er Su Ren Rd Ge Re eee eRe edes 11 222 2 AY Stats ANS coco ee ee Vv eHote vw seule e den EP cabe ER 12 2 2 v4 Peak IO vale acc laud Be eet qa ace pU et tetra Delnaceduacd dar d resta 12 2 2 6 6 Adjust Controls S S ii ena ori Ep KK ite d cO KK KK dns 13 XLO 1 HV ISTIS S 6 saws e Eee ne VP wobei Mi ege meet 13 2 2 6 2 Amplifier Settings 4 aa esca eed Cei UR Eee KI KK KK KK KK KK RR E KK ie 14 2 2 0 9 Preset Setting 55 32 551 3555 DINER aded eG t Eqs 16 2 2 6 4 ADG Setting Sre Prats PERDE outs ek he oh Cees bee Reeve ex EE 20 220 3 obabilizer Se Hin 55 2575535455404431 eee V que RS eee Seek beth peed 21 22515 Ty General Set nps 15 150 ue See De ees Sota ee euet hel etd wee 2X 22 2 2 8 8 Spectrum Memory kek kk kk E t EE qd kk kk kk
85. ed as 4294967295 ticks SHOW TRUE REMAINING Reports the current true time remaining in units of 20 milliseconds 50 ticks per second See also SET TRUE REMAINING Responses G0000000000075 lt CR gt True time remaining reported as disabled G0000000001076 lt CR gt True time remaining reported as 1 tick G4294967295132 lt CR gt True time remaining reported as 4294967295 ticks SHOW_ULD Returns the value of the ULD in channels as a C record SHOW_UNCERTAINTY Returns the current value of the uncertainty for the peak in the uncertainty preset See also SET_UNCERTAINTY Responses UNCE 0000000000008 5 Uncertainty of the peak is 8 5 108 6 FIRMWARE COMMANDS AND RESPONSES SHOW UNCERTAINTY PRESET Returns the current uncertainty preset setting See also SET UNCERTAINTY PRESET Responses UNCE PRES 000000000000000 No preset UNCE PRES 0000000000008 5 Preset set to 8 596 SHOW VERSION Reports the digiDART firmware version number in the form Fmmmm vvv CR where mmmm is a 4 character model designator and vvv is a 3 character version designator Example Responses FDDRT 002 lt CR gt Model digiDART firmware Version 2 reported SHOW_WINDOW Reports the start channel and number of channels in the window of interest in the form Dxxxxxyyyyyccc lt CR gt where xxxxx is the start channel 0 16383 and yyyyy is the number of channels 1 16384 See SET WINDOW for more information about the window of interest Exa
86. ed for a device when an acquisition is started See also SHOW TIME SET DATE SHOW DATE SET TIME START and SHOW TIME START Execution Errors 131137085 lt CR gt The time could not be set due to a hardware malfunction Hardware service may be required SET_TIME_START hour min sec Sets the start time to the specified values Normally the start date and time are set automatically whenever a device is started with the START command See also SHOW_TIME_START SET_DATE_START SHOW_DATE_START SET_DATE and SET_TIME SET_TRIG_SAMPLE setting Selects the triggering source in InSight Mode See LIST_TRIG_SAMP for legal trigger sources SET_TRUE ticks Sets the true time counter to the specified number of ticks The number represents true time in units of 20 ms 50 ticks sec Normally this value is set by the digiDART during data acquisition See also CLEAR_COUNTERS and SHOW_TRUE Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_TRUE_PRESET ticks Sets the true time preset to the specified number of ticks 20 ms tick During data acquisition when the true time counter reaches the preset number of ticks the preset is complete and the acquisition is stopped Setting a true time preset to 0 ticks disables the 90 8 FIRMWARE COMMANDS AND RESPONSES preset The preset should always be set to a multiple of one second See also CLEAR PRESETS and SHOW TRUE PRE
87. ed for backward compatibility 78 6 FIRMWARE COMMANDS AND RESPONSES ENABLE HV Turns on the high voltage enable output of the digiDART See also DISABLE HV and SHOW HV Execution Errors 131137085 lt CR gt The high voltage could not be enabled due to a high voltage shutdown condition ENABLE_NAI Switches the stabilizers to Nal mode The stabilizers use the fine adjustment in Nal mode and the very fine adjustment in Ge mode See DISABLE_NAI ENABLE_OPTI_NEED Enables the reporting of an error when the digiDART needs optimizing ENABLE_OVERFLOW_PRESET Enables the overflow preset Channels that receive a count when they contain 2147483647 counts the maximum number of counts will stop the acquisition if the overflow preset is enabled The channel that caused the preset to complete will contain 2147483647 counts See also DISABLE_OVERFLOW_PRESET and SHOW_OVERFLOW_PRESET commands ENABLE_PZ_AUTOMATIC Enables the automatic pole zero mode See also DISABLE_PZ_AUTO and SHOW_PZ_AUTO ENABLE_PZ_NEED Enables the reporting of an error when the digiDART needs pole zeroing ENABLE_REMOTE Enables the recognition of commands on the alternate communication path If this command is sent to the digiDART via Ethernet it enables command recognition on the serial line ENABLE THRESHOLD AUTOMATIC Enables automatic determination of the positive and negative thresholds See also DISABLE THRESHOLD AUTO SHOW THRESHOLD J AUTO SET THRE
88. entered To retain current value press MENU ENTER 2 Enter MDA Preset Actual Enter the MDA preset in this dialog The value entered here is the desired MDA value MDA Preset User multiplied by the branching ratio and efficiency as described in Section 6 2 The branching ratio is found in the gamma library and the efficiency can be calculated in GammaVision or similar programs Use 5 Clear MDA to turn off this MDA preset off The MDA Preset User is also changed when this value is entered To retain the current setting press MENU ENTER 18 3 Enter MDA Coefficient 4 Enter Low Channel 5 Enter ROI Length 6 Enter Efficiency Yield 7 Enter Nuclide Name 8 Clear MDA 2 THE DIGIDART These are the MDA coefficients used in the MDA calculation see Section 6 2 These coefficients depend on the MDA formula used You can enter any coefficients here but to have the values correspond to the MDA value calculated in the software such as GammaVision use the values shown in the GammavVision dialog for MDA preset The three coefficients are entered as decimal numbers These coefficients are used for all 20 MDA calculations Changing them for one MDA changes them for all MDAs It is only necessary to enter them once This is the beginning of the peak region The region should start in the background region below the peak The three left most channels should be background The region should not be wider than necessary as th
89. er will stay active even if the power is turned off When the stabilizer is enabled the Stabilizer High Voltage T Zero Stabilization Enabled T Gain Stabilization Enabled Center Chan o Center Chan o Width fi Width j Suggest Region Suggest Region Adjustment Adjustment pen 0 Initialize 0 Figure 35 Stabilizer Tab Center Channel and Width cannot be changed 5 5 High Voltage Tab Figure 36 shows the High Voltage tab which allows you to turn the high voltage on or off set and monitor the voltage and choose the Shutdown mode The high voltage is overridden by the detector bias remote shutdown signal from the detector high voltage cannot be enabled if the remote shutdown or overload signals prevent it If an Overload indicator is displayed there is a bad connection in your system If a Shutdown indicator is displayed either the detector is warm or you have chosen the wrong shutdown mode Properties Field Data About Status Presets MDA Preset Nuclide Report Amplifier Ampliier2 ADC Target 3500 Off Actual 3520 Volts Figure 36 High Voltage Tab oa Stabilizer High Voltage r Shutdown ORTEC Volts Enter the detector high voltage in the Target field click On and monitor the voltage in the Actual field Click the Off button to turn off the high voltage 48 Properties x Field Data About Status
90. ergy list shows all the gamma ray energies for the selected nuclide in the library If the application supports efficiency calibration and the digiDART is efficiency calibrated the MDA is entered in the units selected in the application If the unit is not efficiency calibrated e g in MAESTRO which does not support efficiency calibration the MDA field is labeled Correction the efficiency Eff is set to 1 0 and the preset operates as before If the Correction factor is the actual MDA times the efficiency known from other sources the MDA preset will function normally 5 11 Nuclide Report Tab Figure 42 shows the Nuclide Report tab The Nuclide Report displays the activity of up to 9 user selected peaks Once the report is set up you can view the Nuclide Report at any time on the digiDART display The peak area calculations in the hardware use the same methods as the MAESTRO Peak Info calculation see the Software User s Manual so the Nuclide Report display is the same as the Peak Info display on the selected peak in the spectra stored in the PC The calculated value is computed by multiplying the net peak count rate by a user defined constant If the constant includes the efficiency and branching ratio the displayed value is the activity You enter the nuclide label and the activity units The report format and calculations are discussed in detail in Chapter 6 55 digiDART Portable HPGe MCA User s Manual 5 11 1 Add New
91. es needed Any or all of the entries can be changed When finished with the changes click on Update 5 11 3 Delete To remove an entry select the entry and press Delete When you close the Properties dialog all the values entered are written to the digiDART and are used when you view the Nuclide Report on the digiDART display 56 6 CALCULATIONS 6 1 The Nuclide Report The Nuclide Report displays the activity of up to 9 user selected peaks Once the report is set up you can view the Nuclide Report at any time The peak area calculations are the same as the calculations in MAESTRO and other ORTEC software so the Report contents can be duplicated using the spectra stored in the PC The calculated value is computed by multiplying the net peak count rate by a user defined constant If the constant includes the efficiency and branching ratio the displayed value will be activity The nuclide label and the activity units are entered by the user The report has this format cos 13315 21401 cose 11732 Y cost x Yo 6 1 1 Calculations These are the calculations used to generate the Nuclide Report s Activity Uncertainty and Peak values Activity is calculated as follows Ams NetCounts NucCoef LiveTime NucCoef is normally the inverse of efficiency times the branching ratio Note that the efficiency is the ABSOLUTE counting efficiency for the source detector geometry being used Thus in order to get meaningful act
92. ess STORE to switch between lowercase and uppercase letters Jumps the marker to the channel at 1 6 of the display Jumps the marker to the channel at 1 3 of the display Jumps the marker to the channel at 1 2 of the display Jumps the marker to the channel at 2 3 of the display Jumps the marker to the channel at 5 6 of the display Jumps the marker to the right most channel on the display Zoom In Each button press reduces the number of channels displayed by half to a minimum of 240 channels The zoom in view is centered on the marker location This is used as a shift or function key when used in combination with other buttons Press and hold the 8 button press the second button in the combination then release both e lt 8 Left arrow gt moves the marker to the lowest channel ROI 84 Right arrow moves the marker to the next ROI to the right 84 Up arrow Sets the display mode to linear autoscale 841 Sets the display mode to logarithmic 84 3 sets the first point of a new ROI at the current marker location 2 THE DIGIDART Button Spectrum Mode Parameter Text Entry Mode in conjunction 846 sets the endpoint for the new ROI and fills in the ROI This endpoint can be at a lower channel number or energy than the start point but you must start marking with 843 and end with 846 844 removes the ROI if the marker is in an ROI region 847 zooms the hor
93. eters for a specific nuclide peak number This command is used to quickly clear the list of nuclide values CLEAR NUCLIDE ALL Clears all nuclide values This command is used to quickly clear the list of nuclide values CLEAR PRESETS The live time true time ROI integral ROI peak and overflow presets are all set to zero disabled Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken CLEAR_ROI The region of interest flags for the channels in the window of interest see SET WINDOW command in the currently selected device see SET DEVICE command are cleared Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken CLEAR_SPECTRUM num Clears out the single spectrum num stored in stored spectrum memory num is a number between 0 and the value returned by SHOW_SPECTRUM_COUNT CLEAR_SOH Clear the state of health byte CLEAR_SPECTRUM_ALL Clears all stored spectra from stored spectrum memory CLOSE_FILE filename Completes download of file to RAM Disk in the MCB See OPEN_FILE and WRITE_FILE This command may also be used to terminate a download to the FLASH without reprogramming the FLASH 76 6 FIRMWARE COMMANDS AND RESPONSES CLOSE FILE FLASH crc Completes download of FLASH data Cre is the CRC checksum of the data which was downloaded See OPEN FILE FLASH and WRITE
94. functions available DSPEC Plus Bit T2 73 74 75 76 T11 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 APPENDIX A FEATURE MASK BITS Meaning DSPEC Plus style InSight triggering LIST SET TRIG SAMP Multiple inputs per connection for example OCTETE Plus Hardware count rate meter SH CRM Has multiple ZDT modes SET SHOW LIST MODE ZDT Has multi nuclide MDA preset Has MCS Replace then Sum Mode SET RPLSUM Has programmable external dwell voltage capability 1 No Peak Preset feature M CA and OASIS Programmable pulser OASIS Programmable Vacuum HV interlock OASIS Programmable Current HV interlock OASIS 0 Explorable Stabilizer LIST GAIN ADJU LIST ZERO ADJU Has programmable input impedance MCS Advanced shaping time feature has no CUSP digiDART Selectable HV rise time SET SHOW LIST HV RISE SBS 60 Monitor command support SHOW MONI MAX LABEL V ALUE SMART 1 Detector support SHOW SMART DET SHOW SNUM DET SHOW HV RECO Nuclide report SET SHOW NUCL COEF SET SHOW ROI NUCL Interactive Display Features Such as Nuclide Report Advanced Stored Spectra SH SPEC COUNT SET SHOW SPEC ID MOVE 69 digiDART Portable HPGe MCA User s Manual 70 8 FIRMWARE COMMANDS AND RESPONSES Most software communication with the digiDART will be through the CONNECTIONS 32 software layer CONNECTIONS 32 is used by all ORTEC software and is available for other software development Direct
95. hannel as determined by the conversion gain the gain peak width is reduced until the peak fits the device boundaries A gain channel and width must be set before gain stabilization can be enabled Execution Errors 70131128085 CR The specified channel number would create a peak that was less than the minimum width 3 channels or would be outside the device s range 131136084 lt CR gt The command was attempted while gain stabilization was enabled SET GAIN COARSE num This sets the coarse gain to num which must be 1 2 4 8 16 or 32 See also SHOW GAIN COARSE SET GAIN CONVERSION chans Sets the conversion gain The conversion gain defines the number of channels within the device that will used for spectral data This has the effect of altering the resolution of the ADC from 14 bits conversion gain 16384 to 9 bits conversion gain 512 for the device See also SHOW GAIN CONVERSION Legal Commands SET GAIN CONVERSION 0 lt CR gt Conversion gain set to default 16384 SET GAIN CONVERSION 512 CR Conversion gain set to 512 channels SET GAIN CONVERSION 1024 CR Conversion gain set to 1024 channels SET GAIN CONVERSION 2048 CR Conversion gain set to 2048 channels SET GAIN CONVERSION 4096 lt CR gt Conversion gain set to 4096 channels SET GAIN CONVERSION 8192 CR Conversion gain set to 8192 channels SET GAIN CONVERSION 16384 lt CR gt Conversion gain set to 16384 channels SET GAIN FINE value This sets the f
96. he current settings and the spectrum unless the display is locked They can also START and STOP data acquisition However if users try to change settings an Access denied message will be displayed Use 3 Enter Password to enter the administrator password and gain full access If the administrator password is not set all users have full access to all functions To clear the password enter 0 zero for the password then MENU ENTER If the user and administrator passwords are identical the digiDART will grant administrator full access when the user password is entered See Section 4 1 15 NOTE There is no master administrator password If you lose this password contact your ORTEC service representative or our Global Service Center 22 2 THE DIGIDART 3 Enter Password Allows you to enter the administrator password so you can switch to administrator mode and then change the digiDART settings See Section 4 1 15 To exit administrator mode turn the power off and on then enter user password if needed 4 Lock Spectral Display This locks turns off or unlocks displays the spectrum display and Peak Info command The unit must be in administrator mode to lock or unlock the display Select 4 to switch from lock to unlock or unlock to lock The display is not turned off until you leave administrator mode by turning the digiDART off then back on NOTE When the display is locked the unit will not respond to PC based software comm
97. ide count rates and activities in the field The report readouts update in real time for as long as the report screen is displayed so you can have a live reading of the selected nuclides You can select up to 9 gamma ray energies located anywhere in the spectrum The display shows the nuclide name the energy and the calculated value The calculated value is the net area times a factor divided by the live time The factor is user entered If you enter a 1 the value calculated is the net peak count rate By including the efficiency and branching ratio in the factor the value calculated is the activity To set up the ROIs to be monitored on the Nuclide Report screen see Section 2 2 3 To view the Nuclide Report from the spectrum screen press MENU ENTER 9 4 1 16 Administrator and User Passwords The digiDART offers two levels of password security user and administrator The user password prevents any unauthorized startup of the instrument The administrator password prevents non administrators from changing the current digiDART settings but allows them to set and enable the detector high voltage START and STOP data acquisition monitor hardware 37 digiDART Portable HPGe MCA User s Manual status and view the Nuclide Report Note that spectrum locking Section 4 1 16 only works when an administrator password is set The passwords are numerical and are one or more characters in length but cannot be a single zero Assigning
98. ine gain to value Value is a floating point value from 0 45 to 1 0 See also SHOW GAIN FINE SET GAIN NEGATIVE This sets the amplifier input polarity to negative SET GAIN POSITIVE This sets the amplifier input polarity to positive 84 6 FIRMWARE COMMANDS AND RESPONSES SET GAIN WIDTH chans Sets the width in channels for the stabilizer gain peak The gain width must be chosen such that the beginning channel is no lower than channel 0 and the ending channel is no higher than the maximum channel as determined by the conversion gain The gain channel and width must be set before gain stabilization can be enabled The absolute minimum width for the gain peak is 3 channels and the absolute maximum width for the gain peak is 256 channels in Gauss mode In point mode there is no maximum peak width though the chosen width must allow the peak to fit within the device s channel limits as stated above See also SHOW GAIN WIDTH SET GAIN CHANNEL and SHOW GAIN CHANNEL Execution Errors 131128085 lt CR gt The specified number of channels would create a peak that was less than the minimum 3 channel width or would be outside the device s range 131136084 lt CR gt The command was attempted while gain stabilization was enabled SET_GATE_ANTICOINCIDENT Causes the digiDART to use the ADC gate input signal in anticoincident mode See also SET_GATE_OFF SET_GATE_COINCIDENT and SHOW_GATE SET_GATE_COINCIDENT Causes the digiDARTo use
99. ing condition to be met 86 6 FIRMWARE COMMANDS AND RESPONSES at b c CountsinROI MDA Preset gt ___ _ _ Live Time The calculation is performed once every 30 seconds with i starting at 0 and advancing through each of up to 20 unique MDA presets i only advances once the preset has been met Note that a b and c are the same for each of the unique presets Only the ROI range and the MDA preset change when i advances Once i reaches 20 or MDAPreset equals 0 the acquisition terminates SET MDA PRESET MDAPreset PeakNumber Sets or reports the MDAPreset PeakNumber value as shown in the equation in the SET_MDA_COEF description above MDAPreset is usually the product of the desired MDA the yield and the efficiency PeakNumber is a parameter that specifies which of up to 20 0 19 MDA presets to change If PeakNumber is omitted in the set command all MDA preset values will be set to 0 disabled and the supplied value will be applied to MDA Preset 0 This provides compatibility with old GammaVision products SET_MODE_PHA The mode is set to PHA SET_MODE_SAMPLE Starts InSight Virtual Oscilloscope mode SET_NUCLIDE_COEF NucCoef PeakNumber Sets or reports the NucCoef PeakNumber value as shown in the equation above NucCoef is usually the product of the yield and the efficiency PeakNumber is a parameter that specifies which of up to 9 0 8 peaks to change The coefficient can be any value from
100. ing from 0 3 to 2 4 in steps of 0 1 See also SHOW SHAP FLAT SET SHAP RISE value Sets the rise time to value Value is in microseconds ranging from 0 2 to 23 in steps of 0 2 See also SHOW SHAP RISE SET SHUTDOWN index Used in conjunction with the LIST SHUTDOWN command to set the high voltage shutdown setting Index specifies a position in the list of legal shutdown settings which were displayed with the LIST SHUTDOWN command Example SET SHUT 0 Sets the SHUTDOWN to TTL SET SHUT 1 Sets the SHUTDOWN to ORTEC SET SHUT 2 Sets the SHUTDOWN to SMARTI SET SHUTDOWN ORTEC This sets the bias shutdown mode to ORTEC See page 13 SET SHUTDOWN SMARTI Sets the bias shutdown mode to SMART 1 See page 13 SET SHUTDOWN TTL This sets the bias shutdown mode to TTL See page 13 89 digiDART Portable HPGe MCA User s Manual SET THRESHOLD NEGATIVE value Sets the negative threshold to value The negative threshold is normally set automatically by the digiDART See also ENABLE THRESHOLD AUTOMATIC and SHOW THRESHOLD NEGATIVE SET THRESHOLD POSITIVE value Sets the positive threshold to value The positive threshold is normally set automatically by the digiDART See also ENABLE THRESHOLD AUTOMATIC and SHOW THRESHOLD POSITIVE SET TIME hour min sec Sets the time stored in the battery backed up system clock to the specified values hour can be any value from 0 23 min and sec can be any value from 0 59 The current date and time are stor
101. ing the comma or space s that separates the checksum from the command The checksum simply appears as an extra parameter added to the end of the command parameter list For commands that do not normally have parameters the checksum appears as the only parameter separated from the header by one or more spaces All optional parameters must be included in a command if a checksum is to be provided so that the checksum is not mistaken by the MCB API as a parameter For example the SET WINDOW command must include the two optional parameters start and length if the checksum is provided e g SET WINDOW 0 16384 209 8 1 2 Percent Response Records The MCB API responds to all commands with a percent response record that signifies the completion of the command Percent response records contain two error code numbers and a 1 byte checksum as follows 9oaaabbbccc CR where represents the ASCII character aaa represents the macro error code bbb represents the micro error code ccc represents the checksum and CR represents the ASCII carriage return character signifying the end of the record The macro error code represents the general class of error with 0 meaning no error and the micro error code represents the sub class of error with 0 meaning no error Following is a list of all percent responses for the digiDART Unconditional Success 20000000069 CR No errors detected Command executed as specified 000005074 lt CR gt Device al
102. is parameter is displayed at the top left of the spectrum The second Figure 7 Set Up the Status Line status item is marked with 2 and is displayed at the top right The order in which you select items allows you to determine which parameter is shown on the left and right sides of the display Battery Time Remaining Count Rate Count Rate in ROI 2 0 Counts Ja 4 5 Real Time Remaining 8 9 2 2 5 5b Peak Info When you place the marker in a defined ROI and issue Peak Centroid 1332 5 this command it reports the centroid FWHM and net FWHM 2 03 Net Counts 52971 and gross counts for the region Fig 8 Access is denied Gross Counts 83497 ROI Start Channel 4320 when the spectrum display is locked If the marker is not ROI End Channel 4352 in an ROI all values are shown as N A Figure 8 Peak Info 12 2 THE DIGIDART 2 2 6 6 Adjust Controls The list of controls is shown in Fig 9 HV Settings Amplifier Settings Presets Settings ADC Settings Stabilizer Settings Figure 9 Adjust Controls 2 2 6 1 HV Settings This dialog Fig 10 includes the following functions Enable HV Set Bias Voltage 1 Enable HV Sone Turns on the high voltage If no detector SMART 1 View HV SOH or DIM is attached or if HV is in shutdown status the Error Cannot Enable HV message is displayed If Disable HV is displayed the HV is on and pressing 1 will turn it off
103. ivity results as in any counting situation you need to have efficiency factors which are appropriate to the actual counting geometry If NucCoef is set to 1 you will get peak count rate on the display LiveTime 1s the current live time 57 digiDART Portable HPGe MCA User s Manual NetCounts is computed with the following equation NetCounts GrossCounts Background GrossCounts is the sum of the counts in the ROI excluding the first and last 3 channels of the ROI Background is Buckis und AvgCount first 3 chan AvgCount last 3 chan ROIWidth ROIWidth is ROIWidth EndChannel StartChannel 1 6 Uncertainty in percent is calculated as follows GrossCounts Background SOIT Uncertainty Zen EUN 100 NetCounts Peak is the position of the maximum count and is computed with the following equation Peak MaximumROIChan EnergySlope Energylntercept MaximumROlIChan is the channel in the ROI with the most counts If there are no data the center channel of the ROI is used EnergySlope and Energylntercept are the energy calibration values as entered on the digiDART keypad or by software If the values are not present the result is given in channels 58 6 CALCULATIONS 6 2 MDA Preset Calculation The formula for the MDA can be represented as follows a b c Counts in ROI Eff Yield x MDA Live time The MDA values in the MCB are calculated given the constants a b and c i is a index fr
104. izontal axis to maximum expansion 240 channels 849 zooms to minimum expansion maximum number of channels e lt 8 CLEAR gt jump back to menu Zoom Out doubles the number of channels displayed the marker is centered in the display 2 2 Menu Commands The digiDART keypad and display allow you to view or change most of the MCA settings in the field without a host PC This section describes the digiDART menus commands and status screens In addition a quick reference menu tree is included on the last page of the manual after the index Chapter 4 tells how to use the unit in the field The digiDART keypad is simple to use e When you first turn the unit on it starts in spectrum mode Press MENU ENTER to open the Main Menu To select items from the menus press the number buttons e To modify a setting enter the new value then press MENU ENTER To erase a digit press CLEAR To return to the preceding menu press MENU ENTER digiDART Portable HPGe MCA User s Manual e There are two ways to return to spectrum mode from any menu 1 press MENU ENTER until the spectrum is displayed or 2 press CLEAR If you press CLEAR to jump from a menu to spectrum mode you can jump back to that menu by pressing 8 CLEAR e On any entry if you just press MENU ENTER without pressing any other keys the current value will be used that is no change will be made Therefore if you enter a dialog by mistake you c
105. lay Settings as Eu A dou a RES e n 23 Feature mask bits iu sus Coburn 66 Gain stabilizer 21 37 47 59 operation details 22 assem beh 59 GME basen NN I ITIDIMDMMDMDMZ2Mo MIMazR23P 20 General Settings Menus as x RR En 22 Fiehvollase 532 basr bela eed 13 48 InSight Virtual Oscilloscope 45 Tustallatloft s 42 oe bir a an a dan 27 Keypad quick reference 4 6 Lock spectrum display 23 39 MAESTRO ADC SCIUTIBS 5 oen tart o ae 46 amplifier settings 242d oy KK 43 counting presets ioa ete oe KK ex 53 Field Data move view stored spectra 49 BID d Lie od Cede eb K i 43 hardware detector status monitors 50 high voltage setup societe be tx 48 InSight Virtual Oscilloscope 45 instrument specific properties 50 MDA presets 4 ue keyi men S ER ba 54 Nuclide Report setup tab 55 shaping controls deba ex ey eh eee 45 StaDIlIZGT SO sine Eka ay ards Rea kah d 47 Main Ment c s 5ya bac bap dd 10 MDA presets calculation ado ob b ab nak ag 59 directory S vc es sud obese ed ee BO JBZMMMMM 18 Menus ADC BOIS see oeste c SER EBEN 20 Adjust Controls 1 3 ih ihe ERAN 13 Amplifier Settings 2 rae ben A bu 14 Display 234i 9d Saber peta dasa CEPS 23 General Settings caseo ER Ee 27 LIV Setting S se 4ey5 5555a wa lene y Wey ar 13 NIU i aha ad ach wana weh bel d y ART 10 MDA Presets si xara cat adda
106. le The log display is always in autoscale mode You can also do this by pressing 841 3 Normal Switches to linear scale autoscale off The operation is set to PHA This is only needed when you disconnected from the host PC with the digiDART Peak Dieplayed in InSight mode Start Channel End Channel see Section 4 3 1 Display Mode Auto Contrast This shows the current display settings Fig 24 Figure 24 View the Current Display Settings 1 Retrieve Stored Spectrum commands let you view and monitor the contents of the 2 Erase All Stored Spectra digiDART stored spectrum memory 24 1 Retrieve Stored Spectrum Copies the selected spectrum from stored spectrum memory to the live spectrum memory To select the spectrum enter the stored spectrum 3 Spectrum Directory Figure 25 Stored Spectrum sequence number or the spectrum ID To see the Memory list of stored spectrum sequence numbers and IDs press 3 Spectrum Directory The display for selecting a spectrum number or ID is shown 2 THE DIGIDART Figure 26 shows the spectrum number entry display If you enter a spectrum number greater than the number of stored spectra a message is displayed When a spectrum is retrieved the 1 WARNING current live spectral data are lost SOM EEN EISSN Enter Spectrum Number gt Figure 26 Retrieve Stored Spectra 2 Erase All Stored Spectra Deletes all stored spectra from stored spe
107. mple Responses D0000016384094 lt CR gt Window of interest reported as starting at channel 0 and continuing for 16384 channels D0000008192092 lt CR gt Window of interest reported as starting at channel 0 and continuing for 8192 channels first 1 2 D0819208192112 lt CR gt Window of interest reported as starting at channel 8192 and continuing for 8192 channels last 1 2 SHOW_ZDT Not used included for backward compatibility SHOW ZERO ADJ Returns the value of the zero offset for the zero stabilizer SHOW ZERO CHANNEL Reports the center channel for the stabilizer zero peak See also SET ZERO CHANNEL SET ZERO WIDTH and SHOW ZERO WIDTH Responses C00000087 CR Zero channel has not been set C00002089 CR Zero channel is channel 2 lowest possible channel C16382107 CR Zero channel is channel 16382 highest possible channel 109 digiDART Portable HPGe MCA User s Manual SHOW ZERO STABILIZATION Reports the state of zero peak stabilization See also ENABLE ZERO STABILIZATION and DISABLE ZERO STABILIZATION Responses IT lt CR gt Zero stabilization is currently enabled IF lt CR gt Zero stabilization is currently disabled SHOW_ZERO_WIDTH Reports the current width for the stabilizer zero peak See also SET_ZERO_WIDTH SET_ZERO_CHANNEL and SHOW_ZERO_CHANNEL Responses C00001088 lt CR gt Zero width has not been set C00003089 CR Zero width is 3 channels lowest possible width C0
108. nd Analysis Software A66 B32 The digiDART also offers these features e Small enough to mount on a detector Dewar or attach easily to an ORTEC M 1 tripod e Rugged ABS plastic case with a shock resistant elastomer covering The cable between the MCA and detector does not carry high voltage so the digiDART is protected from electrical damage Connects to the host PC via the USB port Long battery life up to 12 hours on a single battery Highly stabile peak shape and peak position with temperature and count rate Optimize detector performance for a given application from the digiDART or from the PC using the InSight Virtual Oscilloscope ORTEC s easy automatic pole zero adjustment Administrator and user passwords entered from the digiDART keypad only not PC Patent number 5 872 363 digiDART Portable HPGe MCA User s Manual software provides added security for your data e Monitor the contents and capacity of the stored spectrum memory e Highly accurate Gedcke Hale extended live time correction method e In the field accessories for ease of use in all conditions The digiDART is the first MCB to support ORTEC s SMART 1 HPGe detector technology which monitors and records the detector s state of health SOH including detector temperature It supports HPGe Nal CZT and other detector types The digiDART can also use our DIM POSNAI and DIM 296 detector interface modules DIMs to supply detector bias
109. nt value of the 24 volt supply in the DIM as delivered to the detector 12 volts This is the current value of the 12 volt supply in the DIM as delivered to the detector 12 volts This is the current value of the 12 volt supply in the DIM as delivered to the detector 24 volts This is the current value of the 24 volt supply in the DIM as delivered to the detector High Voltage This is the current value of the high voltage bias supply in the DIM as delivered to the detector Detector temperature Not available for the digiDART Live detector temperature Not available for the digiDART Battery voltage This is the present voltage of the internal battery Battery full This is an estimate of the amount of power remaining in the battery Battery time remaining This is an estimate of the time remaining when using the internal battery operating in the current mode 52 5 USING THE DIGIDART WITH MAESTRO 5 9 Presets Tab Figure 40 shows the Presets tab MDA presets are shown on a separate tab Amplifier Amplifier2 ADC Stabilizer High Vohage Field Data About Status Presets MDA Preset Nuclide Report The presets can only be set on an a r Uncertainty MCB that is not acquiring data fip Time Penz during acquisition the preset field TT Live Time backgrounds are gray indicating that Start Chan 0 they are inactive You can use any RO Peak wish or all of the p
110. o PZ status bit This bit is returned by the SHOW STATUS command Spectral data can be corrupted if automatic PZ is initiated while a device is collecting data Execution Errors 70131136084 CR The command was attempted while the amplifier was set for a transistor reset preamplifier No action was taken STOP seg mask Stops the acquisition of spectral data The optional segment mask is provided for compatibility with other MCBs and may be any value from 0 to 65535 but is ignored Execution Warnings 000005074 Acquisition already stopped no changes made STOP_OPTIMIZE Stops the optimization in progress The digiDART may be in an indeterminate mode See also START_OPTIMIZE STOP_PZ_AUTOMATIC Stops the optimization in progress The digiDART may be in an indeterminate mode See also START_PZ_AUTOMATIC TERM Sets the digiDART to terminal mode included for backward compatibility TEST mask Performs any combination of the digiDART internal selftests where mask represents a 16 bit integer with each bit set specifying a test as follows Bit 1 Spectral data memory test destroys spectral data Bit 3 Serial line test serial loop back connector required Bit 6 Front panel LED test Execution Errors 004016080 lt CR gt Spectral data memory or mailbox memory failed test 004064083 lt CR gt Serial line failed test 111 digiDART Portable HPGe MCA User s Manual VERIFY CORR FLAT VERIFY SHAPE FLAT VERIFY SHAPE RISE Thes
111. o be used The Eff detector efficiency is determined from the calibration The Yield branching ratio is read from the working library using the nuclide and energy specified The MDA value is the one you have entered in the dialog Counts is the gross counts in the specified region and Live fime is 54 5 USING THE DIGIDART WITH MAESTRO the live time The MDA value is calculated in the MCB given the ampie Ampiez ADC Stabifeer High TAET values a b c Live time Eff and Field Data About Status Presets MDA Preset Nuclide Report Yield The calculated value is MDA Preset Nuclide Energy Add New compared with the MDA value on 120 0000 Ce 1 0a 88 03 n ieg Coced 1173 24 Update the dialog and when it is lower acquisition is stopped Debe MDA Pi esel Coeff ier ls Coefficients A B and C can be Coarrertinn 150 0000 n p nonono l entered as numbers If the applica Nucide F50 m B 000000 uac tion such as ScintiVision supports Energy 117324 kev C fe1 700001 MDA calculations you can click on Llose the Suggest button to enter from an uws internal table the values for the Figure 41 MDA Preset Tab MDA type selected The MDA type should be chosen before the preset is selected here Select the Nuclide and Energy from the droplists The Nuclide list contains all the nuclides in the working library The En
112. om 0 to 19 that represents the 20 unique nuclides CountsinROI is the gross counts in the specified region for the i nuclide and LiveTime is the live time The constants a b and c and the total left hand factor expected value are loaded into the MCB by the user The calculated value right hand side is compared with the expected value and when all are lower acquisition is stopped Note that a b and c are common for all nuclides while the ROI and the preset left hand value are unique for each of the nuclides 6 3 Gain Stabilization The gain stabilizer Section 2 2 6 5 requires a peak in the spectrum to monitor the changes in the gain of the system amplifier The gain stabilizer controls the amplification factor of a separate amplifier so that the peak will be maintained in its original position The input pulse height to channel number relationship is Channel number Intercept Gain pulse height where Intercept The channel number of the zero height input pulse Gain The relation between pulse height and channel number slope of the curve Changes in either the intercept or gain can affect the positions of all the peaks in the spectrum When used with the zero stabilizer both the zero intercept and the gain slope will be monitored to keep all the peaks in the spectrum stabilized The zero stabilization and gain stabilization are separate functions in the digiDART but both will affect the position of the peaks in the spe
113. om 0 to 50 000 cps Linearity Integral Nonlinearity lt 0 025 over top 99 5 of spectrum measured with a mixed source Fe at 5 9 keV to Y at 1836 keV e Differential Nonlinearity lt 1 measured with a BNC pulser and ramp generator System Temperature Coefficient e Gain 50 ppm C typically 30 ppm C e Offset 10 ppm C with rise and fall times of 12 us and flattop of 1 us similar to analog 6 us shaping Overload Recovery At maximum gain recovers to within 246 of rated output from x1000 overload in 2 5 non overloaded pulse widths measured using the InSight Virtual Oscilloscope Pulse Pileup Rejector Automatically set threshold Pulse pair resolution typically 500 ns 63 digiDART Portable HPGe MCA User s Manual 4 Automatic Digital Pole Zero Adjustment Performed from the digiDART keypad or software Can be set automatically or manually Remote diagnostics via InSight Virtual Oscilloscope mode in MAESTRO Digital Gated Baseline Restorer Adjustment of the restorer rate High Low and Auto controlled from the digiDART keypad or software ADC Gate Not available for PLUS transistor reset preamplifier or SMART 1 detectors Accepts a positive TTL input via the DIM s Inhibit BNC Signal must occur prior to and extend 0 5 us beyond peak detect Software selectable as off coincidence and anticoincidence LLD Digital lower level discriminator set in channels Hard cutoff of data in channels below
114. ope mode for viewing the pulses can only be accessed via MAESTRO or similar programs with the digiDART connected to the PC 4 1 Normal Operation This section walks you through the normal steps needed for first time use of the digiDART in the field and saving the spectra on the laboratory PC Once set up the digiDART saves all the settings and restores them on the next startup On any entry if you just press MENU ENTER without pressing any other keys the current value will be used that is no change will be made Therefore if you open a dialog by mistake you can just press MENU ENTER to go back without changing anything For complete details on the menus and dialogs refer to Section 2 2 In addition a quick reference menu tree is included on the last page of the manual after the index CAUTION The digiDART is splashproof but not watertight To avoid equipment failure protect the unit from prolonged or heavy rainfall and from immersion 4 1 1 Battery The battery will last up to 12 hours in full operation with the detector The battery is charged internally when external power is supplied Before starting a series of measurements you should check the battery To check the battery turn on the digiDART power press MENU ENTER then 1 View Status If the percent power is below 15 1 hour remaining you should install a new battery To remove the battery turn off the power open the door at the base of the instrument
115. or example to set the Live time preset press 1 now and enter the preset value in seconds The value is a decimal number with resolution of 20 milliseconds The entered value is truncated to the nearest valid value 36 4 USING THE DIGIDART IN FIELD MODE To turn off a preset enter a 0 not a blank then MENU ENTER Entering a blank or nothing then pressing MENU ENTER vwill keep the existing preset Press 7 to view the live real count and integral preset settings The uncertainty and MDA settings are viewed on their own separate displays Press MENU ENTER 4 times to return to the spectrum display The MDA preset is used to stop the counting when all of the nuclide MDAs are met The MDA setup process is discussed on page 18 The MDA preset requires the detector efficiency and nuclide branching ratio both of these can easily be found or calculated with software such as GammaVision 4 1 14 Stabilizers The digiDART is very stable so unless you see peak drift the stabilizers can be turned off or disabled To disable the stabilizers press MENU ENTER 6 5 then 7 to show the current state If both show as DISABLED press MENU ENTER 4 times to return to the spectrum display If either or both are enabled press MENU ENTER then 1 for gain to disable it or 4 to disable zero Then press MENU ENTER 3 times to return to the spectrum display 4 1 15 Nuclide Report The Nuclide Report is a very useful tool for monitoring nucl
116. out shutting down MAESTRO the PC or the USB hub Note that if MAESTRO is running when you disconnect the digiDART the software will display a detector not responding message on the status line at the bottom of the MAESTRO window When you reconnect the digiDART to the PC simply reselect it from the detector droplist on the MAESTRO Toolbar NOTE When the digiDART is connected to the PC the keypad will be disabled and the display will read LCD Display Disabled Host USB Connected In this configuration the digiDART will function as a standard ORTEC CONNECTIONS 32 MCB 3 2 Cabling Figure 30 shows the digiDART connectors at the top of the instrument 12 15V DC USB Connect the power supply cable to the lt 12 15V DC connector When the digiDART is supplied with external 12 V power the installed battery is charging The external DETECTOR battery charger is only needed when you wish lo up Sum to charge batteries outside the digiDART Attach the SMART 1 HPGe detector or DIM Figure 30 digiDART Connectors cable to the DETECTOR connector Finally connect the USB port to the PC You can connect and disconnect the digiDART from the PC without restarting Windows or MAESTRO NOTE When the digiDART is connected to the PC the keypad is disabled and the display reads only USB connected The digiDART functions in this configuration just like other ORTEC CONNECTIONS 32 MCBs 28 3 INSTALLATION AND STARTUP 3
117. position the palm of your hand under the opening and tap the digiDART s base gently against your palm The battery will dislodge and slide into your hand Note the battery contacts and install the new battery in the same orientation If you need to change the battery in the field you should stop the acquisition and turn off the HV to the detector then turn off the power The acquisition will stop and the HV will turn off as soon as the battery is removed However to maintain the highest spectrum quality you should stop the acquisition and turn off the detector HV manually Change the battery then power up the digiDART and the detector HV Wait approximately 2 minutes for the detector to stabilize 31 digiDART Portable HPGe MCA User s Manual then restart acquisition To change the battery when external power is connected it is not necessary to turn off the digiDART 4 1 2 Detector Connect the digiDART to your cooled detector and power on the digiDART Now set the HV shutdown mode to protect the detector Set the shutdown mode by pressing MENU ENTER 6 Adjust Controls 1 HV Settings 3 Set Shutdown For a SMART 1 HPGe Detector press 3 SMART for other types of detectors select 1 TTL or 2 ORTEC If the detector does not have a shutdown signal use 1 TTL Now set the HV to the value for the detector by pressing 2 Set Bias Voltage and entering the correct value The polarity is set in the SMART 1 or DIM Now turn on the HV
118. press CLEAR before you have saved the current spectrum with the STORE button the spectrum will be lost e Saves the currently displayed spectrum in No action Switches the most the digiDART stored spectrum memory recently entered When a spectrum is stored you can alphabetic character assign it an 8 character ID see between lowercase and Section 2 2 2 If you try to store a uppercase spectrum when the stored spectrum memory is full the digiDART displays a Write Error Spectrum Memory is Full message Moves the marker to the right Decimal point assigned to a number button Decreases the vertical scale making Decreases display contrast Used in conjunction with peaks look taller Use it in conjunction the number buttons with the Zoom In and Zoom Out buttons cycles through the 3 buttons 7 and 9 respectively alphanumeric characters assigned to a number button Increase the vertical scale making peaks Increases display contrast Used in conjunction with look shorter Use it in conjunction with the number buttons the Zoom In and Zoom Out buttons cycles through the 3 buttons 7 and 9 respectively alphanumeric characters Jumps the marker to channel 0 0 space underscore Press the number button then the up or down arrow to move through digiDART Portable HPGe MCA User s Manual Spectrum Mode Menu Mode Parameter Text Entry Mode in conjunction with Qe and Q the letter symbol choices Pr
119. put because the MCB is not unproductively occupied processing noise pulses The Upper Level Discriminator sets the level of the highest amplitude pulse that will be stored This level establishes an upper level cutoff by channel number for ADC conversions 5 4 Stabilizer Tab The digiDART has both a gain stabilizer and a zero stabilizer These are discussed in detail in Sections 6 3 and 6 4 The Stabilizer tab Fig 35 shows the current values for the stabilizers The value in each Adjustment section shows how much adjustment is currently applied The Initialize buttons set the adjustment to 0 If the value approaches 90 or above the amplifier gain should be adjusted so the stabilizer can continue to function when the adjustment value reaches 100 the stabilizer cannot make further corrections in that direction The Center Channel and Width fields show the peak currently used for stabilization 47 digiDART Portable HPGe MCA User s Manual To enable the stabilizer enter the Center Channel and Width values manually or click on the Suggest Region button Suggest Region reads the position of the marker and inserts values into the fields If the marker is in an ROI the limits of the ROI are used If the marker 1s not in an ROI the center channel is the marker channel and the width is 3 times the FWHM at this energy Now click on the appropriate Enabled checkbox to turn the stabilizer on Until changed in this dialog the stabiliz
120. r of stop bits 1 2 For example SET CONFIG UART 09600NS81 sets the baud rate to 9600 disables parity checking sets the number of bits to 8 and the number of stop bits to 1 SET CORRECTION FLAT value This sets the flattop correction to value The flattop correction is normally determined with the OPTIMIZE command See also SHOW CORRECTION FLAT SET DATA start chans value If the optional start and chans parameters are included in this command the range of channels specified by start and chans is loaded with value If start and chans are not specified sets all channels of spectral data in the window of interest see SET WINDOW command to the specified value ROI flags are not affected 82 6 FIRMWARE COMMANDS AND RESPONSES SET DATA APPLICATION stringl string2 This is used to store information in the digiDART internal memory that can be used by other programs such as sample descriptions and energy calibrations CONNECTIONS 32 makes use of this feature String the data identifier 32 bytes maximum string2 the data 128 bytes maximum SET DATE day month year Sets the date stored in the battery backed up system clock to the specified values Day can be any value from 1 31 month any value from 1 12 and year any value from 0 99 The current date and time are stored for a device when an acquisition is started See also SHOW DATE SET TIME and SHOW TIME SET DATE START day month year Sets the start date to the specified v
121. r rise times and flattops can be selected which will increase the FWHM To set the rise time press MENU ENTER 6 2 3 then enter the rise time The rise time is a decimal number If you don t enter one of the exact values say you enter 11 3 the digiDART selects the closest value e g 11 4 Now set the flattop by pressing 4 then the flattop The flattop is a decimal number If you don t enter one of the exact values suppose you enter 1 1 the closest value is selected e g 1 2 You can view the settings now by selecting 0 Press MENU ENTER 3 times to return to the spectrum display 4 1 8 Optimize The next step is to optimize the detector see Section for a detailed discussion of this operation Optimization adjusts the pole zero and the flattop tilt for the best resolution for the detector Use a source positioned so the detector count rate is approximately 5000 cps To monitor the count rate display it as one of the status line options as discussed in Section 4 1 4 When the count rate is satisfactory press MENU ENTER 6 2 7 then 1 to start the optimization The display will show that the optimization is underway The progress is shown by a series of dots If you need to stop the process because of no counts or too high a count rate press any key to abort If you abort you must fix the problem and redo the optimization before collecting any spectra Press MENU ENTER to return to the Amplifier dialog It is not n
122. re ot reae Ovis 33 4 1 7 Rise Time and Flattop oua orto ode KK KK CRUS PRO nl KK KK KK KK KK toy 34 2 128 ODE SEN datu cc SCIEN rrr 34 4 1 9 Detector State ot Health ues pa sna xta ken e dan ttr i eae eee 34 AMO Calibration 6c 4 Stade etui Xe ka ayak p a a eie a ven aed a lak kb amp kak a IE SUR C dan dcs 35 TIL T DISBISV BBSES V seeren d B han EP E E hae E EA Reeth eee A OAE 36 4 1 12 Setting ROIs in the Spectrum Display kk kk KK RR KK RR KK KK 36 d 1 15 DiesetS ec oso ua eee eds n ya dl Re b ye orco be RT eot dae NE Ode 36 2451 12 Stabilizers 2h ke Al an n ore e ue e b dw Dene beoe een 37 A Ne 1 INuclide REPOT ces vari avit tacta ul it ok WA plata e n d hed ca AA 37 4 1 16 Administrator and User Passwords eleeleeeeeeeee 37 4 1 17 Locking the Spectrum Display 0 KK KK KI KK KI KK eee eee 39 2 118 Collec np sSpeclEa sd wie sk dena a r Bee Re Eie mene qe vede 40 4 1 19 Downloading Spectra to the PC AK eens 4 4 2 Should You Take a Laptop Into the Field 20 0 0 RR RR RR RR KK KK 4 4 2 1 Operation witha PC ooo oA 2 354 Dang Q22 2A2 hl Bet eM e o W W 2 Ay halk 4 2 3 TreubleshOOune ow cc toe ee cia O KRN QA e l wd Lae c Eee ee eae ROR ERU He 42 4 3 1 If You Disconnected While In InSight Virtual Oscilloscope Mode 42 4 3 2 The digiDART Will Not Turn on uer yr hae KK KK KK pete Rech s 42 4 3 3 If You Forgot
123. ready started or stopped The START or STOP command was ignored 000006075 lt CR gt Device preset already exceeded The START command was ignored 000016076 lt CR gt START requested but amplifier not pole zeroed since last power up START was attempted anyway 000032074 lt CR gt START requested but high voltage not enabled START was attempted anyway 000064079 lt CR gt Specified parameter was rounded to the closest legal value 72 000048081 lt CR gt 000037079 lt CR gt 000053077 lt CR gt 000038080 lt CR gt 000054078 lt CR gt Power Up Alert 001000070 lt CR gt 003000072 lt CR gt Command Syntax Errors 129001082 lt CR gt 129002083 lt CR gt 129003084 lt CR gt 129004085 lt CR gt 129005086 lt CR gt 129006087 lt CR gt 129007088 lt CR gt 129132087 lt CR gt Communication Errors 130001074 lt CR gt 130002075 lt CR gt 130003076 lt CR gt 130004077 lt CR gt 130005078 lt CR gt 130006079 lt CR gt 130007080 lt CR gt 130008081 lt CR gt 130128084 lt CR gt 130129085 lt CR gt 130131078 lt CR gt 8 FIRMWARE COMMANDS AND RESPONSES Note that the above responses can be combined to indicate a combination of warnings such as Amplifier was not pole zeroed nor was high voltage enabled The START was attempted anyway Device already started and high voltage not enabled The command was ignored Device already started high voltage not enabled and amplifier w
124. recently entered calibration from either software or the digiDART will be written into the stored spectrum memory when the spectrum is stored The calibration will remain with the spectrum when it is downloaded to the PC and stored as an SPC file 4 1 11 Display Energy Now select MENU ENTER then 4 to show the current status line selections Press 2 to remove the marker channel and press 1 to display the marker energy Press MENU ENTER 2 times to return to the spectrum display 4 1 12 Setting ROIs in the Spectrum Display The digiDART lets you mark any number of 1490 keV 1000 sec ROIs on the spectrum display They are shown as horizontal lines immediately beneath the spectrum Fig 31 Any ROIs saved with the spectrum are displayed when the spectrum is viewed in MAESTRO ScintiVision etc Note that these are not the same as the ROIs for the Nuclide Report discussed in Section 4 1 15 To set an ROI in the spectrum mode put the marker on the starting channel and press lt 8 3 gt then move the marker to the end channel and press lt 8 6 gt Figure 31 ROI Indicator Lines The ROI is shown by a bar below the spectrum The bar will always be shown even if it is a small region in a condensed display To delete an ROI put the marker in the ROI and press lt 8 4 gt 4 1 13 Presets To set a preset to stop the collection at a specific point press MENU ENTER 6 3 then the number of the preset type you want F
125. resets at one time To Rai Integral disable a preset enter a value of zero m Suggest Region If you disable all of the presets data mls aue J acquisition will continue unti manually stopped Figure 40 Presets Tab When more than one preset is enabled set to a non zero value the first condition met during the acquisition causes the MCB to stop This can be useful when you are analyzing samples of widely varying activity and do not know the general activity before counting For example the Live Time preset can be set so that sufficient counts can be obtained for proper calculation of the activity in the sample with the least activity But if the sample contains a large amount of this or another nuclide the dead time could be high resulting in a long counting time for the sample If you set the ROI Peak preset in addition to the Live Time preset the low level samples will be counted to the desired fixed live time while the very active samples will be counted for the ROI peak count In this circumstance the ROI Peak preset can be viewed as a safety valve The values of all presets for the currently selected MCB are shown on the Status Sidebar These values do not change as new values are entered on the Presets tab the changes take place only when you Close the Properties dialog Enter the Real Time and Live Time presets in units of seconds and fractions of a second These values are stored internally with
126. roperties When the digiDART is connected to the PC it is completely software controlled The MCB Properties dialog contains all of the instrument controls including ADC setup parameters acquisition presets amplifier gain adjustments pole zero controls and access to the InSight Virtual Oscilloscope Just move from tab to tab and set your hardware parameters then click on Close it s that easy Note that as you enter characters in the data entry fields the characters will be underlined until you move to another field or until 5 seconds have lapsed since a character was last entered During the time the entry is underlined no other program or PC on the network can modify this value 5 1 Amplifier Tab Figure 32 shows the controls on the Amplifier tab It the controls for Gain Baseline Restore Preamplifier Type Input Polarity and optimization Be sure that all of the controls on the tabs have been set before clicking the Start Auto optimize button NOTE The changes you make on this tab take place immediately There is no cancel or undo for this dialog Gain Set the amplifier coarse gain by selecting from the Coarse droplist then adjust the Fine gain with the horizontal slider bar or the edit box in the range of 0 45 to 1 00 The resulting effective gain is shown at the top of the Gain section The two controls used together cover the entire range of amplification from 0 45 to 100 43 digiDART Portable HPGe MCA User s M
127. rrors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_LENGTH_SAMPLE length Sets the number of points in the InSight mode display to the specified value Normally this setting would remain at 1000 SET_LIVE ticks Sets the live time counter to the specified number of ticks The number represents live time in units of 20 ms 50 ticks s Normally this value is set by the digiDART during data acquisition See also CLEAR COUNTERS and SHOW LIVE Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_LIVE_PRESET ticks Sets the live time preset to the specified number of ticks 20 ms tick During data acquisition when the live time counter reaches the preset number of ticks the preset is complete and the acquisition is stopped The preset should always be set to a multiple of 1 second Setting a live time preset to 0 ticks disables the preset See also CLEAR_PRESETS and SHOW_LIVE_PRESET Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_LLD chan Sets the lower level discriminator to chan which must be between 0 and 16383 See also SHOW_LLD SET MDA COEF a b c Sets the coefficients in the MDA preset calculation to the specified values A b and c are floating point values The MDA preset checks for the follow
128. rum 7 Zero Stab Width This is the width in channels of the peak region to be used It should be slightly wider than the peak but not overly wide 21 digiDART Portable HPGe MCA User s Manual 8 Initialize Zero Stab Resets the zero peak stabilization adjustment to unity no adjustment 9 Enable Nal This is an enable disable toggle Enable switches the bias supply to the Nal high current low voltage mode Disable switches to the Ge low current high voltage mode The HV is turned off when this command is sent 0 View Current Settings This displays the stabilizer settings currently being used 2 2 7 7 General Settings These commands Fig 22 control instrument access Change User Password calibration and the LCD display Change Admin Password Enter Password race pene Display 1 Change User Password Calibrate dos Use this to set a numeric password to prevent Display unauthorized use of the instrument The password is limited to 9 digits When the user password has been set the digiDART prompts for it on power up To clear the password enter O zero for the password then press MENU ENTER Figure 22 General Settings 2 Change Admin Password Use this to set a numeric administrator password that prevents other users from changing the current digiDART settings The password is limited to 9 digits When the administrator password has been set users as distinguished from administrators can view t
129. rum The display shows the nuclide name the energy and the calculated value The calculated value is the net area times a factor Figure 29 Real Time Nuclide divided by the live time The factor is user entered If you Report Display enter a 1 the value calculated is the net peak count rate By including the efficiency and branching ratio in the factor the value calculated is the activity See Section 2 2 3 for detailed instructions on setting up the ROIs to be monitored by this report 26 3 INSTALLATION AND STARTUP 3 1 Software and Hardware Installation Installing the digiDART and the MAESTRO 32 MCA Emulation Software takes just three easy steps Do not connect the digiDART to your PC until MAESTRO has been installed 3 1 1 Install MAESTRO 32 and the CONNECTIONS 32 Driver Update Kit Install the accompanying version of MAESTRO 32 must be v6 04 or higher according to the instructions in the MAESTRO Software User s Manual selecting the USB based instruments hardware option If your MAESTRO CD is accompanied by a CONNECTIONS 32 Driver Update Kit P N 797230 follow the installation instructions for the update kit which supersede the MAESTRO instructions 3 1 2 Connect the digiDART to the USB Port on the PC With the PC powered on connect the digiDART to the PC s USB port Windows will indicate that the digiDART has been detected and will start up the new hardware installation wizard Click on Next indicate that
130. s of the live time counter in units of 20 ms 50 ticks s See also CLEAR COUNTERS and SET LIVE Responses G0000000000075 lt CR gt Live time reported as 0 ticks G0000000001076 lt CR gt Live time reported as 1 tick 20 ms G4294967295132 lt CR gt Live time reported as 4294967295 ticks over 23000 days SHOW_LIVE_PRESET Reports the current live time preset in units of 20 ms 50 ticks s See also CLEAR_PRESETS and SET LIVE PRESET 99 digiDART Portable HPGe MCA User s Manual Responses G0000000000075 lt CR gt Live time preset reported as disabled G0000000001076 lt CR gt Live time preset reported as tick G4294967295132 lt CR gt Live time preset reported as 4294967295 ticks SHOW_LIVE_REMAINING Reports the current live time remaining in units of 20 ms 50 ticks s See also SET_LIVE_REMAINING Responses G0000000000075 lt CR gt Live time remaining reported as disabled G0000000001076 lt CR gt Live time remaining reported as 1 tick G4294967295132 lt CR gt Live time remaining reported as 4294967295 ticks SHOW_LLD Shows the lower level discriminator setting See also SET_LLD Responses C00050092 The LLD is 50 SHOW_MARKER Returns the channel number of the marker SHOW_MDA PeakNumber Reports current MDA for the MDA Preset selected by PeakNumber PeakNumber is assumed to be 0 if not supplied Example response MDA 0000000000010 7 SHOW MDA COEF Reports the current settings for coefffi
131. ses C00001088 lt CR gt Gain width has not been set C00003089 CR Gain width is 3 channels lowest possible width C00256100 lt CR gt Gain width is 256 channels highest possible width in Gauss mode C16383108 lt CR gt Gain width is 16383 channels highest possible width in point mode with gain channel set to 8192 SHOW_GATE Reports the current mode of operation of the ADC gate input See also SET_GATE_OFF SET_GATE_COINCIDENT and SET_GATE_ANTICOINCIDENT Responses FOFF lt CR gt Reports the ADC gate is off or ignored FCOI lt CR gt Reports the ADC gate is in coincident mode FANT lt CR gt Reports the ADC gate is in anticoincident mode SHOW_HV Reports the current high voltage and the status of the high voltage power supply in the form Dvvvvvsssssccc Where vvvvv represents the current output voltage if the high voltage is enabled or the rear panel high voltage setting if the high voltage is disabled sssss represents the status of the high voltage bias supply as a 16 bit decimal number with the following bit definitions Bit 0 LSB Bias supply polarity O positive 1 negative Bit 1 Bias supply overload O overload 1 normal Bit 2 High voltage enabled O disabled 1 enabled Example Responses D0200000003077 lt CR gt 2000 V negative not overloaded disabled D0200000002076 lt CR gt 2000 V positive not overloaded disabled D0200000007082 lt CR gt 2000 V negative not overloaded enabled
132. ses suleuueH ou Aieneg HL33v71V3as si al puan sBumas sjeseld Piomssed ulwipy ebueyd z sbulneg 1o du v z WHMS Piomssed esn ebueyd L sbumes AH k pio1juo2 Xead S UNOD 19N 2108 opi vlc 0 eui peed euuguo uoneoo JOSuND Z E Red L IOH P 100 1IS31 08222 ga euin jeou e1j2edgs p 10 S Ily ese13 Z AG1eu3 uopeoo7 10sn5 L L 3ALLOV 0 108 epi qi4ejua 186522 oos OUI n unJ4joeds paJ01S 9A9ujeH yodey epijonN A ouew unnoeds sBu 1eS jesouey Sjo11u02 snfpv OjU eod aul SNIS sIOH apijonN QI 19103 SEIS MIA m NO lt f 0609 9 digiDART Portable HPGe MCA User s Manual 116
133. t CR gt The specified number of channels would create a peak that was less than the minimum width 3 channels or would be outside the devices range 131136084 lt CR gt The command was attempted while zero stabilization was enabled SHOW_ACTIVE Returns a 1 if the digiDART is active 1 e acquiring spectral data or 0 if it is not active Responses C00000087 lt CR gt Not active C00001088 lt CR gt Active SHOW_ADC_CONV Returns the ADC conversion gain SHOW_BLRE Shows the baseline restorer time constant in microseconds See also SET_BLRE Responses BLUE 000000000000091 Time constant is 91 us SHOW_BLRE_AUTOMATIC Shows whether automatic selection of the baseline restorer constant is off or on Responses IT lt CR gt Automatic baseline is enabled IF lt CR gt Automatic baseline is disabled 92 6 FIRMWARE COMMANDS AND RESPONSES SHOW CONFIGURATION Returns a record that indicates the hardware configuration of the MCB The record contains information about the number of segments in an MCB device always 1 for the digiDART and the current conversion gain for each segment The record is organized as follows J1638400001aaaaa00000 65 zeros here for total of 75 zeros 00000ccc where aaaaa represents the conversion gain for the one and only segment in the currently selected device and ccc represents the record checksum See the section on response records in this chapter for more information about response records and
134. t can be positive or negative Choosing a positive value results in a flattop that slopes downward choosing a negative value gives an upward slope Alternatively the optimize feature on the Amplifier tab can set the tilt value automatically This automatic value is normally the best for resolution but it can be changed on this dialog and in the InSight mode to accommodate particular throughput resolution tradeoffs The optimize feature also automatically adjusts the pole zero setting The dead time per pulse is 3 x Rise Time 2 x Flattop Width In the Pole Zero section the Start button performs a pole zero at the specified rise time and other shaping values Unlike the optimize feature it performs a pole zero for only the one rise time The pole zero Stop button aborts the pole zero and is normally not used When you are satisfied with the settings Close the Properties dialog and prepare to acquire data Once data acquisition is underway the advanced user might wish to select MCB Properties and click on the InSight section s Start button to adjust the shaping parameters interactively with a live waveform showing the actual pulse shape or just to verify that all is well Section provides detailed instructions on using the InSight mode 5 3 ADC Tab This tab Fig 34 contains the Gate Conversion Gain Lower Level Discriminator and Upper Level Discriminator controls In addition the current real time live time and count
135. t set of quality control tests designed to expose any flaws in materials or workmanship Permanent records of these tests are maintained for use in warranty repair and as a source of statistical information for design improvements Repair Service If it becomes necessary to return this instrument for repair it is essential that Customer Services be contacted in advance of its return so that a Return Authorization Number can be assigned to the unit Also ORTEC must be informed either in writing by telephone 865 482 4411 or by facsimile transmission 865 483 2133 of the nature of the fault of the instrument being returned and of the model serial and revision Rev on rear panel numbers Failure to do so may cause unnecessary delays in getting the unit repaired The ORTEC standard procedure requires that instruments returned for repair pass the same quality control tests that are used for new production instruments Instruments that are returned should be packed so that they will withstand normal transit handling and must be shipped PREPAID via Air Parcel Post or United Parcel Service to the designated ORTEC repair center The address label and the package should include the Return Authorization Number assigned Instruments being returned that are damaged in transit due to inadequate packing will be repaired at the sender s expense and it will be the sender s responsibility to make claim with the shipper Instruments not in warranty should follow
136. te functions in the digiDART but both will affect the position of the peaks in the spectrum The stabilization operates by keeping a peak centered in an ROI you have defined The ROI should be set symmetrically about the center of a peak with reasonably good count rate in the lower channels of the spectrum The ROI should be about twice the FWHM of the peak If the region is too large counts not in the peak will have an effect on the stabilization 6 5 Optimization The digiDART is equipped with both automatic pole zero logic and automatic flattop logic These features automatically choose the best pole zero and flattop tilt settings Note that if you selected 2 TRP transistor reset the preamplifier type for this digiDART the optimize function does not perform the pole zero As with any system the digiDART should be optimized any time the detector is replaced or if the coarse gain is changed For optimization to take place the digiDART must be processing Patent number 5 872 363 Patent number 5 821 533 60 6 CALCULATIONS pulses The detector should be connected in its final configuration before optimizing Position a radioactive source near the detector so the count rate is approximately 5000 cps To monitor dead time go to the Main Menu and press 1 View Status During optimization pole zeroes are performed for several rise time values and the digiDART is cycled through all the rise time values for determination of
137. the ADC gate input signal in coincident mode See also SET_GATE_OFF SET_GATE_ANTICOINCIDENT and SHOW_GATE SET_GATE_OFF Causes the digiDART to ignore the state of the ADC gate input signal See also SET_GATE_COINCIDENT SET_GATE_ANTICOINCIDENT and SHOW_GATE SET_HV value This sets the HV bias to value in volts SET_ID lt id string gt Sets the sample id string This string can be up to 16 characters long and can be set to any arbitrary value The id string is intended to uniquely identify the sample being analyzed The id string is also set by the BARCODE command and is stored with each spectrum acquired in field mode See also SHOW_ID Execution Errors 131132080 lt CR gt No ID string was specified No action was taken Examples SET ID Site 123 SET ID Sample 123456789 85 digiDART Portable HPGe MCA User s Manual SET INTEGRAL PRESET count Sets the ROI integral preset to the specified count During data acquisition when the sum of the counts contained in the channels that have the ROI flag set reaches the integral preset count the preset is complete and the acquisition is stopped The actual number of counts in the ROI integral may exceed the preset value by up to 512 counts due to the pipelined architecture of the digiDART Setting an integral preset to 0 counts disables the preset The integral preset may be set to from 0 disabled to 4294967295 counts See also CLEAR PRESETS and SHOW INTEGRAL PRESET Execution E
138. this acquisition including the presets ROIs calibration and SOH bit from the live memory to stored spectrum memory This entire set of data can be downloaded to the host PC using a program such as MAESTRO The file can then be saved as an SPC file Ron Jenkins R W Gould and Dale Gedcke Quantitative X Ray Spectrometry New York Marcel Dekker Inc 1981 pp 266 267 2 1 INTRODUCTION The stored spectra are retained until you delete them even when the digiDART is powered off and has been disconnected from all external and battery power The digiDART has 1 5 Mbytes of spectrum memory available for stored spectra Each stored spectrum consumes 4 bytes x the number of channels in the spectrum plus 400 bytes of settings information The spectrum storage required for different conversion gains is shown in Table 1 In addition the table shows the total number of spectra that can be stored in spectrum memory if all of the spectra have the same conversion gain You can collect and store spectra with any combination of conversion gain settings Table 1 Capacity of Spectrum Memory According to Conversion Gain Setting Used Conversion Memory Required Gain bytes a 16k 65936 24 The digiDART has a Spectrum Memory menu see Section 2 2 for more details that allows you to view the contents and remainder of the spectrum memory The Spectrum Directory command allows you to view the spectrum identification for the spectra in sp
139. tings This displays all the amplifier settings currently being used Fig 15 2 2 6 3 Preset Settings This dialog is shown in Fig 16 The Device Busy message means the unit is collecting data and this parameter cannot be changed until the unit is stopped To continue changing the presets return to spectrum mode and press STOP 1 Live Time Preset This dialog is used to enter the live time preset in seconds This stops acquisition when the live time reaches this value To clear the preset enter O zero and press the MENU ENTER key 2 Real Time Preset Coarse Gain Fine Gain Rise Time Flat Top Pole Zero Baseline Restore Preamp Type Input Polarity Figure 15 View Current Amplifier Settings Live Time Preset Real Time Preset ROI Integral Preset ROI Peak Preset Uncertainty Preset MDA Presets View Current Settings Figure 16 Presets This dialog is used to enter the real time preset in seconds This stops acquisition when the real time reaches this value To clear the preset enter 0 zero and press the MENU ENTER key 16 3 ROI Integral Preset 2 THE DIGIDART This dialog is used to enter the ROI integral preset This stops the acquisition when the sum of all counts in all ROIs in the spectrum reaches this value To clear the preset enter 0 zero and press the MENU ENTER key 4 ROI Peak Preset This dialog is used to enter the ROI peak preset This stops the acquisition when an
140. umber with the following bit definitions Bit 0 LSB Bias supply polarity O positive 1 negative Bit 1 Bias supply overload O overload 1 normal Bit 2 High voltage enabled O disabled 1 enabled Bit 3 Unused Bit 4 Amplifier PZ d since initialization O normal 1 needs PZ ing Bit 5 Optimization since initialization 02normal 1 needed Bits 6 7 Unused Bit 8 Amplifier automatic PZ 1 Auto PZ in progress 0 normal Bit 9 Optimization O normal 1 in progress Bits 10 14 Unused Bit 15 MSB Reserved SHOW_THRESHOLD_AUTOMATIC See also SET_THRESHOLD_AUTOMATIC Responses IT lt CR gt Automatic threshold is enabled IF lt CR gt Automatic threshold is disabled 106 6 FIRMWARE COMMANDS AND RESPONSES SHOW THRESHOLD NEGATIVE See also SET THRESHOLD NEGATIVE Responses THR NEG 0000379791 Negative threshold is 379791 SHOW THRESHOLD POSITIVE See also SET THRESHOLD POSITIVE Responses THR POS 00000126811 Positive threshold 1s 126811 SHOW TIME Reports the time from the battery backed up system clock in the form Nhhhmmmsssccc lt CR gt where hhh represents a 3 digit integer hour 0 23 mmm represents a 3 digit integer minute 0 59 and sss represents a 3 digit integer second 0 59 See also SET TIME SET DATE and SHOW DATE Example Responses N010054017052 lt CR gt Time returned 10 54 17 10 h 54 min 17 s N020013037050 lt CR gt Time returned 20 13 37 20 h 13 min 37 s SHOW_TIME_START
141. use with handheld computers without Windows the low level commands are given in Section 8 2 41 digiDART Portable HPGe MCA User s Manual 4 3 Troubleshooting 4 3 1 If You Disconnected While In InSight Virtual Oscilloscope Mode If digiDART was in InSight mode when you disconnected it from the PC it will stay in InSight mode until it is changed You must switch the digiDART out of InSight mode to collect data If the spectrum display is unlocked the digiDART will display the message Display enabled not in PHA mode To return to PHA mode click on MENU ENTER 7 Display 2 Set Display Mode PHA If the spectrum display is locked enter the administrator password then 2 Set Display Mode PHA 4 3 2 The digiDART Will Not Turn on Replace the battery or connect to external power Check that the battery is properly installed 4 3 3 If You Forgot the Password If you have forgotten the user password start the digiDART enter the administrator password and enter a a new user password If there is no administrator password or you have forgotten it too contact your ORTEC service representative 4 3 4 MAESTRO Does Not Connect with the digiDART If properly installed and functioning MAESTRO software or other CONNECTIONS 32 programs cannot find and communicate with the digiDART check the following The digiDART is not turned on e The USB cable is not properly connected e The digiDART display is locked e The Master Instrument
142. ussion on Marks in the Software User s Manual In the automatic mode the current value is shown on the InSight sidebar For a low count rate system the value will remain at about 90 Preamplifier Type The digiDART uses Resistive Feedback preamplifiers Optimize The digiDART is equipped with both automatic pole zero logic and automatic flattop logic The Start Auto optimization button uses these features to automatically choose the best pole zero and flattop tilt settings Note that if you selected Transistor Reset as the Preamplifier Type for this digiDART the Start Auto button does not perform the pole zero As with any system the digiDART should be optimized any time the detector is replaced or if the flattop width is changed For optimization to take place the digiDART must be processing pulses The detector should be connected in its final configuration before optimizing Position a source such that the input count rate is approximately 5000 cps Monitor the count rate with either the Peak Info or Input Count Rate command U S Patent 5 912 825 44 5 USING THE DIGIDART WITH MAESTRO Click on Start Auto The optimize command is sent to the digiDART at this time and if the digiDART is able to start the operation a series of short beeps sounds to indicate that optimization is in progress When optimizing is complete the beeping stops During optimization pole zeroes are performed for several rise time values and th
143. ve spectrum is shown in the lower right The spectrum ID is the eight character alphanumeric value stored with the spectrum The stored spectra cannot be viewed or stored in the PC until they are moved to the active spectrum position To move a spectrum from the stored memory to the active memory enter the spectrum number and click on Move Use the up down arrow buttons to scroll through the list of spectra The label on the lower right does not update until a spectrum is moved The numbers are the same as the numbers shown on the digiDART display in the stored spectrum list Note that this only moves the spectrum inside the digiDART To save the current active spectrum to the PC disk use the File Save commands in the PC based application 49 digiDART Portable HPGe MCA User s Manual The Acquire Download Spectra command can also be used to download and save all the stored spectra to the host PC Be sure to read the Software User s Manual for details on selecting the proper conversion gain and spectrum file format before downloading This tab Fig 38 displays hardware and firmware information about the 5 7 About Tab currently selected digiDART as well ru eee erg een Permit Minimi as the data Acquisition Start Time digiDART s n 241 and Sample description In addition the Access field shows whether the MCB is currently locked with a Saree password Read Write indicates that Calb ation source 1714 the MCB is unlocked Rea
144. w Terminates acquisition when data in any channel exceeds 2 1 2 billion counts Digital Spectrum Stabilizer controlled from the digiDART or software e Stabilization Peak centroid zero and gain channel 2 to 16384 stabilization window width zero and gain 1 to 256 channels e Zero Correction Resolution 64 channels with a minimum adjustment of 0 1 channel out of 16384 total channels Gain Correction Resolution 0 00025 from 99 5 to 100 5 in 4096 steps 7 1 1 Electrical and Mechanical Dimensions digiDART The digiDART is shaped to fit your hand the maximum dimensions are 20 cm x 10 cm x 7 5 cm 8 in x 5 in x 3 in e DIM The DIM is shaped for easy mounting the maximum dimensions including handles are 12 cm x 8 2 cm x 3 3 cm 4 7 in x 3 2 in x 1 3 in Weight e digiDART 900 gm 1 9 Ib e DIM 240 gm 0 5 Ib Operating Temperature Range 10 to 60 C including LCD display Battery 7 2 V lithium ion camcorder battery Charging circuitry and battery management circuitry internal to digiDART Battery inserted through door in case The compartment is semi sealed and protects against penetration of dirt and moisture Battery can be changed without loss of data in spectrum memory Battery life with ORTEC low power preamplifier and HPGe detector is up to 12 hours 65 digiDART Portable HPGe MCA User s Manual 7 1 2 Connectors DETECTOR Preamp Power 1 W only 12V 12V 24V 24V 2 G
145. xample Responses FSite 123 lt CR gt ID set to Site 123 FSample 123456789 lt CR gt ID set to Sample 123456789 SHOW INTEGRAL start_chan number_of_chans Reports the sum of the specified group of spectral data channels If start chan and number of chans is not provided SHOW INTEGRAL reports the sum of all channels in the currently selected segment that have their ROI flag set 98 6 FIRMWARE COMMANDS AND RESPONSES Responses G0000000000075 lt CR gt Integral reported as 0 G4294967294131 lt CR gt Integral reported as 4294967294 G4294967295132 lt CR gt Integral reported as greater than or equal to 4294967295 maximum reportable value SHOW_INTEGRAL_PRESET Reports the current ROI integral preset value For more information about the ROI integral preset see SET_INTEGRAL_PRESET See also SHOW_INTEGRAL Responses G0000000000075 lt CR gt Integral preset reported as 0 G4294967295132 lt CR gt Integral reported as 4294967295 SHOW_INTEGRAL_REMAINING Reports the current ROI integral remaining value For more information about the ROI integral remaining see SET_INTEGRAL_REMAINING See also SHOW_INTEGRAL Responses G0000000000075 lt CR gt Integral remaining reported as 0 G4294967295132 lt CR gt Integral reported as 4294967295 SHOW_LENGTH_SAMPLE Reports the number of points in the InSight Mode Waveform Response C010000088 1000 points in the waveform SHOW LIVE Reports the content
146. y channel in any ROI reaches this value To clear the preset enter 0 zero and press the MENU ENTER key 5 Uncertainty Preset This shows the dialog in Fig 17 to enter the uncer Enter Uncertainty Preset tainty preset and region to be used This stops the E EOM DAD acquisition when the uncertainty of the selected peak View Settings reaches this value Enter the low channel and length first Enter Uncertainty Preset 2 Enter Low Channel 3 Enter ROI Width 4 View Settings This is the percent uncertainty for the peak that will stop Figure 17 Uncertainty Preset the acquisition The calculation is described in Section 6 1 To clear the preset enter 0 zero and press the MENU ENTER key This is the beginning of the peak region The region should start in the background region below the peak The three left most channels should be background The region should not be wider than necessary as the unnecessary width increases the uncertainty value This is the number of channels for the peak region The region should be wide enough to end in the background above the peak The three right most channels should be background The region should not be wider than necessary as the unnecessary width increases the uncertainty value This shows the three values entered above as well as the current uncertainty in the peak region 17 digiDART Portable HPGe MCA User s Manual 6 MDA Presets This function lets
147. you do not wish to connect to the internet or the Microsoft website to locate the driver choose the automatically locate driver option and follow the remaining prompts to completion You will now be ready to run the MCB Configuration program so that MAESTRO and other CONNECTIONS 32 software can recognize the digiDART 3 1 3 Run the MCB Configuration Program to Build a List of Available Detectors From the Windows Start menu select MAESTRO 32 and MCB Configuration The MCB Configuration program will locate all of the powered on ORTEC CONNECTIONS 32 MCBs attached to the local PC and to any network PCs display a master list of the instruments found and allow you to enter customized instrument numbers and descriptions For complete instructions on building and customizing this Master Instrument List see the MAESTRO 32 Software User s Manual 3 1 4 Attaching More Than One digiDART to the PC Once the drivers have been installed for one digiDART simply attach subsequent units to any available USB port on the PC or attached USB hub and re run the MCB Configuration program 27 digiDART Portable HPGe MCA User s Manual REMINDER Be sure to run MCB Configuration any time you add new digiDART or any other ORTEC MCBs to establish communication between the MCBs and the spectroscopy software 3 1 5 Connecting to and Disconnecting from the PC The USB connection allows you to connect digiDARTs to and disconnect them from a USB port with
148. you select a setting the display returns to the Amplifier Settings menu Auto This sets the baseline restorer time constant to the automatic mode This is the normal setting 2 Fast This sets the baseline restorer to operate in the fast restore mode for high count rate situations 3 Slow This sets the baseline restorer to operate in the slow restore mode for low count rate situations 7 Optimize This performs the optimize and pole zero process For best results the digiDART must be collecting data with a dead time less than 1096 Optimization does not start until you press 1 on the next dialog to indicate that the unit is ready to start If you wish to return to the previous menu at this time press MENU ENTER During optimization a row of dots is displayed to show progress To abort the Optimize process press MENU ENTER 15 digiDART Portable HPGe MCA User s Manual 8 Preamp Type The preamplifier type must be set for the type of detector connected This is true for both SMART 1 and DIMs Press MENU ENTER to leave the setting unchanged Resistive Resistive feedback preamplifier 2 TRP Transistor reset preamplifier 9 Input Polarity This sets the polarity for the input signal from the detector GEM detectors have positive output and GMX LEPS and LOAX detectors have negative output This is true for both SMART 1 and for DIMs Press MENU ENTER to leave the setting unchanged Positive 2 Negative 0 View Current Set

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