Home

DSPEC Pro

Contents

1. 2 15 36 91 PRTOUSHDUL 3624 28 ape Sema Setar bales 26 27 Time CONSANE sepeser Denis Sa ee boa see oe 25 Transist r Resto ib ais Oe tiG sh adlee boas bed 25 Troubleshooting 2 2 5 5 500 ay S aeeeb cup ax 43 Uncertainty Preset despa tanien Saeed oxy ou 40 Upper level discriminator ULD 34 ZOT Mod 24 455 Sabet bend ater ah iad oad 2 9 zero dead time see ZDT mode 34 Zero stabilization o bcis be Vath aaah iad eas So 34 TI ANZ Ss espar ak eins Sey ae Droge esa 34 97 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Intentionally blank 98
2. 37 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Security State of Health This is OK if the security test was passed at the end of the last spectrum acquisition This is available only for SMART 1 detectors 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 current 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 This is the detector temperature at the time the current spectrum acquisition stopped This is available only for SMART 1 detectors Live detector temperature This is the detector temperature at the current time This is available only for SMART 1 detectors Battery voltage Not used in the DSPEC Pro Battery full Not used in the DSPEC Pro Battery time remaining Not used in the DSPEC Pro 38 794380D 0914 2 GETTING STARTED 2 3 9 Presets Figure 23 shows the Presets tab Properties for DSPR 0008 MDA presets are on a separate tab A
3. Use the ZDT Off mode when the counting rate is expected to be constant during the time taken to acquire the spectrum e Use the ZDT CORR_ERR mode when the counting rate is expected to change or might change significantly during the time required to acquire the spectrum 13 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Avoid using the NORM_CORR mode because the spectroscopy software will default to analyzing the LTC spectrum and will ignore the ZDT spectrum 1 6 4 3 More Information Visit our website or contact your ORTEC representative for more detailed information Application note AN56 Loss Free Counting with Uncertainty Analysis Using ORTEC s Innovative Zero Dead Time Technique http www ortec online com pdf an56 pdf General gamma spectroscopy technical papers http www ortec online com papers reprints htm General 1 7 DSPEC Pro SMART 1 HPGe Detector Support ORTEC s SMART 1 Detector technology is a great advance in the operation of HPGe detectors and is a major enhancement to data and chain of custody integrity The SMART 1 detector has a high voltage supply included so the DSPEC Pro does not contain a high voltage power supply For older detectors a detector interface module DIM is used to supply the HV for the detector The SMART 1 detector monitors and reports on vital system functions Also its identification serial number can be read by a controller such as the DSPEC
4. ix ORTEC DSPEC Pro 1 INTRODUCTION The DSPEC Pro is the next generation in digital signal processing based gamma ray spectro meters from ORTEC Perhaps the most versatile digital spectrometer on the market today the DSPEC Pro features all of the spectral acquisition MCA emulation and computer control you expect from our DSPEC family of instruments plus specialized features for more challenging gamma ray spectroscopy applications The DSPEC Pro offers superior performance for more applications than any other gamma ray spectrometer delivered across a high speed USB con nection Whether your application is in nuclear power non destructive analysis research physics homeland security real time monitoring or nuclear safeguards the DSPEC Pro gives you exceptional ease of use flexibility rock solid count rate and peak position stability and impressive overall performance 1 1 Why the DSPEC Pro ORTEC digital signal processing DSP offers more options in optimizing the output signal of high purity germanium HPGe detectors The DSPEC Pro builds on our DSP techniques and combines them with the proven technologies of the DSPEC family in one compact economical package with high speed USB connectivity no other instrument comes close for HPGe applications 1 1 1 DSPEC Pro Technologies Resolution Enhancer In ORTEC DSPEC products the flattop width parameter of the trape zoidal filter automatically corrects for ball
5. 0914 ENABLE_RENH Sets the DSPEC Pro to Resolution Enhancer mode See also SHOW_RENH ENABLE_THRESHOLD_AUTOMATIC Enables automatic determination of the positive and negative thresholds See also DISABLE_THRESHOLD_AUTO SHOW_THRESHOLD_AUTO SET_THRESHOLD_ NEGATIVE and SET_THRESHOLD_POSITIVE ENABLE_THRESHOLD_SAMPLE ENABLE_TRIGGER_SPECIAL No function in the DSPEC Pro included for backward compatibility ENABLE_TRIGGER Enables the Sample Ready connector Acquisition will then start when an external trigger occurs on the Sample Ready connector or when the TRIGGER command is issued See also TRIGGER DISABLE_TRIGGER SHOW_TRIGGER SET_TRIGGER_POLARITY and SHOW_TRIGGER_POLARITY ENABLE_ZDT Sets the DSPEC Pro to ZDT mode See SET_MODE_ZDT for information on selecting the ZDT mode ENABLE_ZERO_STABILIZATION Enables the stabilization of the zero peak See also DISABLE_ZERO_ STABILIZATION SHOW_ZERO_STABILIZATION and INITIALIZE_ZERO_STABILIZATION INITIALIZE Returns the DSPEC Pro including flash to the factory default settings and simulates a power down power up cycle for the MCB after a simulated loss of battery backed up memory CAUTION Before issuing this command protect the DIM by turning off the detector bias and physically disconnecting the detector cable from the DSPEC Pro rear panel INITIALIZE_GAIN_STABILIZATION Resets the gain peak stabilization adjustment to unity no adjustment This value is reported as 2048 by the S
6. 17 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 The next line shows the current high voltage setting HV the current high voltage status ON OFF SHDN shutdown or OVLD overload and the shutdown mode TTL ORTEC or SMART Ifa SMART 1 detector is attached the DSPEC RT 36 6 LT 36 6 Pro displays a line immediately beneath the high RTP 200 0 LTP 210 0 voltage line this line is blank for other detector types compare Figs 6 and 7 On the left are the DT 0 1 ICR 41 word SMART and the first 10 characters of the Sey las Adee ISS Ae SMART 1 detector s serial number This is the HV OV OVLD TTL same value returned by the SHOW_DET_SNUM command On the right is the detector tempera MCB ID 1 ture in kelvins DSPEC PRO V 002 USB Figure 7 The DSPEC Pro Display for a The next line shows the ID number for this Non SMART 1 Detector DSPEC Pro as set by the MCB Configuration program and displayed in the Master Instru ment List see the MAESTRO user manual for more information on the MCB Configuration pro gram and the Master Instrument List The last line on the display gives the firmware version for this DSPEC Pro 2 1 1 2 Controls ON OFF To power up the DSPEC Pro press ON OFF It takes up to 20 seconds for the display to appear To turn off the instrument press ON OFF The DSPEC Pro is designed to avoid accidental power down so acquisition isn t interrupted The displa
7. 68 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES Bit 1 Negative baseline threshold Bit 2 Baseline restorer gate 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 Not used included for backward compatibility SET_SHAP_FLAT value Sets the width of the flattop to value Value is in microseconds ranging from 0 3 to 2 4 us 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 8 to 23 us 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 SMART SET_SHUTDOWN_ORTEC This sets the bias shutdown mode to ORTEC SET_SHUTDOWN_SMART Sets the bias shutdown mode to SMART SET _SHUTDOWN_TTL This sets the bias shutdown mode to TTL 69 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SET_THRESHOLD_NEGATIVE value Sets the negative threshold to value The negative threshold i
8. ROI peak count preset 39 stabilizer SUID oat Sie ta e aa 34 uncertainty preset s ay tel ee yey 40 upper level discriminator 34 zero dead time ZDT mode 34 Enhanced throughput mode 3 Feat re mask DIES 500 4 pure Ya eg uel eb oy 49 AMON ew sinnen each cunn ota ae ek eh our 27 ballistic deficiti 2 255 659 oe a ae aaas 8 Tilt e ag irice Nk Bah orgs ata De sched 25 27 Wa eas cory eld Seed yt a a e eB ates 27 Gain stabilization s on n bese sea ox 34 nitaleta a a eg hn ech eye 34 1s 684 61 6 FF ere nem en en a 35 Sithi Mode seansai ta as ee oe eyes 27 Mark 525 ti Siteh bath aye eRe acre ech ors 29 TS tA ANON rss Siok ach cy oe Ca ae tl ee ees 19 Integration UME opty bly oe Pah eas tlle bees 26 List mode SET _MODE _LIST 93 Live tme 5 a Bis bos edie Sed haben Sg 39 Low Frequency Rejector LFR 5 Lower level discriminator LLD 34 MDA presets ik be Pedy hee ree eae 40 INOISE 2 s2i dis Satie Sars Oe eel EN 25 PUI ZS isn ost pana a Aa a Oe 25 POlEZErO ss anpa E n EGA 25 27 Presets see Acquisition presets 39 Rea UMC in ta Deb eich od tha See aan Soe 39 Resistive Feedback 2005 25 ReSOlimOn seeren con En bela 26 27 Resolution Enhancer 5 4 32 RISC TUNG erratean saa is ae ee bes 25 26 SMART 1 detector 2 14 17 37 State of health SOH
9. of counts in the peak will not be correct When a supported ORTEC MCB operates in ZDT mode it adjusts for the dead time losses by taking very short acquisitions and applying a correction in real time that is as the data are coming in to the number of counts in the spectrum This technique allows the gamma ray flux to change while the acquisition is in progress yet the total counts recorded in each of the peaks are correct The resulting spectrum has no dead time at all in ZDT mode the data are correc ted not the acquisition time Thus the net counts in a peak are divided by the real time to deter mine the count rate ZDT mode has a unique feature in that it can store both the corrected spectrum and the uncor rected spectrum or the corrected spectrum and the uncertainty spectrum Therefore supported MCBs allow you to choose between three ZDT Mode settings on the ADC tab under MCB Properties Off NORM_CORR and CORR_ERR Table 1 shows which spectra are collected in the three possible ZDT modes Table 1 ZDT Modes Mode Uncorrected ZDT Corrected ZDT Error Spectrum Spectrum Spectrum Off ZDT Disabled Yes No No NORM_CORR ZDT LTC Mode Yes Yes No CORR_ERR ZDT ERR Mode No Yes Yes 1 6 1 Off Uncorrected Spectrum Only In this mode only the uncorrected spectrum live time and real time with dead time losses also called the live time corrected or LTC spectrum is collected and stored in the SPC file Th
10. 12 us might achieve a small improvement in resolution For planar detectors such as ORTEC s GLP Si Li IGLET and IGLET X Series operating at longer rise times frequently gives improved resolution 2 5 Troubleshooting 2 5 1 MAESTRO Does Not Connect with the DSPEC Pro If properly installed and functioning MAESTRO software or other CONNECTIONS programs cannot find and communicate with the DSPEC Pro check for the following The DSPEC Pro is not turned on The USB cable is not properly connected Check the Master Instrument List on the computer to ensure that the DSPEC Pro is on the list If it is not listed shutdown and restart the DSPEC Pro then re run the MCB Configuration program according to Section 2 2 4 43 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 See the CONNECTIONS Driver Update Kit instructions for more detailed information on using MCB Configuration 44 3 SPECIFICATIONS 3 1 DSPEC Pro Display 240 x 160 pixel backlit LCD provides status information instrument ID bias infor mation live and real time Maximum System Throughput gt 100 000 cps depends on shaping parameters Enhanced Throughput Mode Protection time from 0 1 us to 200 us in 25 ns increments LFR Mode Highest Throughput Lowest Throughput minimum Protection Time maximum Protection Time Off Rise Time flattop 2 x Rise Time Flattop 3 x Rise Time 2 x Flattop 6 x Rise Time 3 x F
11. 4 Run MCB Configuration to Communicate With Your MCBs IMPORTANT This is an abbreviated discussion of the operation and use of the MCB Configuration program We strongly recommend that you read the instructions for the CONNECTIONS Driver Update Kit for complete details on the command line arguments that change how the program searches for MCBs customizing MCB ID Numbers and Descriptions changing your Windows firewall settings to allow MCB access across a network enabling additional device drivers and troubleshooting 1 Make sure the DSPEC Pro is connected and powered on 2 Connect and power on all other local and network ORTEC instruments that you wish to use as well as their associated PCs Otherwise the MCB Configuration program will not detect them during installation Any instruments not detected can be configured at a later time 3 To start the software type mcb in the Search programs and files box on the Windows Start menu then click the MCB Configuration search result or open the Windows Start menu and click MAESTRO then MCB Configuration The MCB Configuration program will locate all of the powered on ORTEC MCBs on the local computer and the network and display the list of instruments found the Master Instrument List Fig 10 If you wish you may enter customized instrument ID numbers and descriptions Section 2 2 4 2 When you close the dialog any changes you have made to an ID number or description wi
12. Digital Gamma Ray Spectrometer User s Manual 794380D 0914 To switch to LFR mode click the Amplifier PRO tab under Acquire MCB Properties and mark the Low Frequency Rejector checkbox see Section 2 3 3 Note that you cannot optimize or pole zero the DSPEC Pro while in LFR mode The Optimize feature should be used with the LFR filter off checkbox unmarked Subsequent measurements can then be taken with the LFR filter on 1 5 Ballistic Deficit and Adjusting the Flattop Duration In germanium detectors it takes a variable amount of time to collect all of the charge released in the detector diode when a gamma ray deposits energy in the detector The duration of this charge collection time depends on the dimensions of the detector the geometry of the electrodes and the points at which energy is deposited in the detector A small planar detector has charge col lection times that vary from 50 ns to 100 ns whereas a large coaxial detector is characterized by charge collection times that vary from 100 ns to 700 ns The variability of the charge collection time within a specific detector is the source of the resolution degradation described by the ballistic deficit effect The ballistic deficit becomes a significant source of resolution degradation when very short shaping times are selected in order to reduce dead time and improve the high counting rate limit For a digital filter having the shape of a symmetrical triangle in the time domain t
13. Electrical and Mechanical Dimensions e DSPEC Pro 8 1 cmH x 20 3 cm W x 24 9 cm D 3 2 in x 8 in x 9 8 in e DIM 11 2cmHx 3 13 cm W x 6 5 cm D 4 4 in x 1 25 in x 2 6 in 47 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Weight e DSPEC Pro 1 0 kg 2 2 lb e DIM lt 240 gm 0 5 Ib Operating Temperature Range 0 to 50 C including LCD display 3 1 2 Connectors DETECTOR Miulti pin connector 13W3 carries the following Preamp Power 1 W only 12V 12V 24V 24V 2 GND Amp In Normal amplifier input Inhibit For TRP or gate Battery Power 5 12 V for DIM Control for HV SMART 1 HPGe detector control USB High speed USB for communication with computer 12 15V DC External power input from wall mounted dc power supply 12 V dc lt 1 25 A center contact positive The connector is RAPC712 Switchcraft 5 5 mm x 2 5 mm SAMPLE CHANGE OUT Rear panel BNC connector TTL compatible SAMPLE READY IN Rear panel BNC connector accepts TTL level signal from sample changer Software selectable polarity 3 2 HPGe High Voltage Detector Interface Modules The DSPEC Pro offers high voltage supply flexibility in the form of modules that connect the detector to the MCA and provide bias and SMART 1 support if appropriate These modules have an input connector that connects to the DETECTOR connector discussed in Section 3 1 2 On a SMART 1 detector the high voltage module will be hardwired to
14. SET_UNCERTAINTY Responses UNCE 0000000000008 5 Uncertainty of the peak is 8 5 87 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 5 SHOW_VERSION Reports the DSPEC Pro firmware version number in the form Fmmmm vvv lt CR gt where mmmm is a 4 character model designator and vvv is a 3 character version designator Example Responses FDSPR 002 lt CR gt Model DSPEC Pro 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 0O 16383 and yyyyy is the number of channels 1 16384 See SET_WINDOW for more information about the window of interest Example 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 D0819208192112 lt CR gt Window of interest reported as starting at channel 8192 and continuing for 8192 channels SHOW_ZDT Reports if ZDT mode is enabled Responses IF ZDT mode disabled IT ZDT mode enabled SHOW_ZERO_ ADJ Returns the value of the zero offset for the zer
15. _LIST Sets the DSPEC Pro to list mode See also SHOW_MODE SET MODE PHA Sets the mode to PHA SET_MODE_SAMPLE Starts the InSight Virtual Oscilloscope mode SET_MODE_ZDT mode Sets the ZDT mode LIST MODE_ZDT can be used to determine which modes are valid Mode 0 standard indicates that a normal and corrected spectrum should be stored Mode 1 enhanced indicates that an error and a corrected spectrum should be stored ENABLE_ZDT must be issued to turn on ZDT mode SET_OUTPUT port value This sends the value to the port This command can be issued without entries for port and value because the DSPEC Pro has only one port If you wish to specify a port number it must be zero for this unit See also SHOW_OUTPUT See also STEP_OUTPUT 67 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SET_OUTPUT_HIGH output num Sets the Change Sample output to the high level The DSPEC Pro has only one sample changer BNC therefore if you include a value for output num it must be zero output num is provided for compatibility with other ORTEC instruments See also STEP_OUTPUT SET_OUTPUT_LOW output num Sets the Change Sample output to the low level The DSPEC Pro has only one sample changer BNC therefore if you include a value for output num it must be zero output num is provided for compatibility with other ORTEC instruments See also STEP_OUTPUT SET_PEAK_PRESET count Sets the ROI peak preset to the specif
16. a 1 if the DSPEC Pro 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_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 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 DSPEC Pro 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 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_CORRECTION_FLAT Shows t
17. accompanying MAESTRO Software User s Manual as well as the man uals for GammaVision Renaissance ISOTOPIC and our other spectroscopy software For the purposes of this manual when we refer to MAESTRO we mean the ORTEC MCA emulator analysis application you are using e g MAESTRO GammaVision ISOTOPIC 16 2 1 1 Front Panel Figure 5 shows the DSPEC Pro front panel 2 GETTING STARTED 2 1 The DSPEC Pro ORTEC DSPEC Pro Figure 5 DSPEC Pro Front Panel 2 1 1 1 The Display The DSPEC Pro has a 240 x 160 pixel LCD display for viewing counting settings and status high voltage setting and status stabilizer settings SMART 1 detector status and shutdown mode When connected to a computer via the USB con nector an indicator is displayed in the lower right Figure 6 shows the layout of display for a DSPEC Pro with a SMART 1 detector attached RT RTP LT and LTP are respectively the actual real time real time preset live time and live time preset r RT 36 6 LT 36 6 RTP 200 0 LTP 210 0 DT 0 1 ICR 41 GainStab OFF ZeroStab OFF HV 0V SHDN SMART SMART 42 N21741A 92 K MCB ID 1 DSPEC PRO V 002 USB Figure 6 The DSPEC Pro Display Showing Presence of a SMART 1 Detector DT and ICR are the dead time in percent and input count rate in counts per second CPS GainStab and ZeroStab show the current setting for the gain and zero stabilizers respectively
18. and click 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 2 3 2 1 InSight Mode The InSight display Fig 15 shows the actual sampled waveform in the digital processing units on a reference graticule The Properties dialog remains active and can be used to change settings while viewing the pulses As none of the traditional analog signals are available in the DSPEC Pro this mode is the only way to display the equivalent amplifier output pulse Note that at the bottom of the window the marker channel is displayed in units of time To exit the InSight mode and return to the PHA display press lt Esc gt or go to the Insight section on the Amplifier 2 tab and click Stop The PHA mode is set to STOP when you enter the InSight mode 27 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 The Status Sidebar changes from the PHA mode controls to the InSight controls for adjusting the peak display On the left is a vertical scrollbar for adjusting the vertical offset of the wave form The value of the offset is shown on the display Double clicking the mouse in the scrollbar will set the vertical offset to the vertical value of the channel at the marker position This lets you conveniently zoom in on a particular part of the waveform such as the tail for pole zero ing ot InSight DS
19. are processed with gating in Coinci dence mode a gating input signal must be present at the proper time 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 ns beyond peak detect peak maximum 33 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 ZDT Mode See Section 1 6 for a for DSPR 0008 detailed discussion of this feature Use this droplist to choose the Off i A Pars Maa p LTC spectrum only or CORR_ERR N 2 ERR and ZDT spectra mode If a oe a raar Ea ZDT mode is selected both spectra Sane Lower Level Disc 50 H are stored in the same spectrum oF Upper Level Disc 1eses H SPC file If you do not need the ZDT spectrum you should select Off Real Time Live Time 0 00 0 00 Count Rate 0 In MAESTRO the display can show either of the two spectra Use Qose lt F3 gt or Acquire ZDT Display Select to toggle the display between the two spectra In the Compare mode lt F3 gt switches both spectra to the other type and lt Shift F3 gt switches only the compare spectrum This allows you to make all types of comparisons Figure 18 DSPEC Pro ADC Tab Conversion Gain This 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 en
20. detector temperature are available only for SMART 1 detectors For non SMART 1 detectors they show N A The parameters displayed are Detector State of Health This is OK if all the SOH are OK and ERR if any one is ERR 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 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 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 This is OK if the detector temperature has stayed below the high temperature limit set in the detector since the last time the SOH was cleared This is available only for SMART 1 detectors 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
21. digital signal pro cessing by allowing you to adjust the delay between the peak detect and the start of processing of the next pulse The dead time for a conventionally processed pulse is the sum of the pulse s rise time flattop and fall time By contrast the dead time in ORTEC s Enhanced Throughput Mode can be as little as the rise time plus the flattop These two scenarios are illustrated in Fig 1 The DSPEC Pro lets you set a protection time PT following a peak detect that blocks 3Patent number 5 872 363 Patent number 5 912 825 Ron Jenkins R W Gould and Dale Gedcke Quantitative X Ray Spectrometry New York Marcel Dekker Inc 1981 pp 266 267 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 subsequent peak detects until the protection time has elapsed Note that the conventional dead time illustrated in Fig 1 is the same as the maximum protection time in Enhanced Throughput Mode The protection time settings with the low frequency rejector LFR filter off range between Minimum PT highest throughput J x rise time 1 x flattop Maximum PT 2 x rise time 1 x flattop With LFR on the protection time settings range between Minimum PT Maximum PT 3 x rise time 2 x flattop 6 x rise time 3 x flattop 1 3 Resolution Enhancement Mode Corrects for Charge Trapping When a gamma ray interacts with a germanium detector mobile electrons and holes are
22. from spectrum Linearity e 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 Gain lt 50 ppm C typically lt 30 ppm C e Offset lt 3 ppm C with rise and fall times of 12 us and flattop of 1 us similar to analog 6 us shaping Pulse Pileup Rejector Automatically set threshold Pulse pair resolution typically 500 ns Automatic Digital Pole Zero Adjustment Can be set automatically or manually Remote diagnostics via Insight Virtual Oscilloscope mode in MAESTRO Digital Gated Baseline Restorer Software controlled adjustment of the restorer rate Fast Slow and Auto 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 the LLD setting ULD Digital upper level discriminator set in channels Hard cutoff of data in channels above the ULD setting Ratemeter Monitor the input count rate on the DSPEC Pro display or computer screen 46 794380D 0914 3 SPECIFICATIONS Battery Internal battery backed up memory to mai
23. 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 Tilt can be positive or negative Choosing a positive value results in a flattop that slopes down ward 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 approximately 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 For the more advanced user the InSight mode lets you directly view all the parameters and adjust them interactively while collecting live data To access the InSight mode go to the Insight section on the Amplifier 2 tab and click Start The InSight mode is discussed in more detail in the following section When you are satisfied with the settings you are ready to acquire data Once data acquisition is underway you may wish to return to MCB Properties
24. our CONNECTIONS Programmer s Toolkit with Microsoft ActiveX Controls A11 Use the DLL interface call MIOComm or the ActiveX control UCONN s Comm method to send commands to instruments and receive responses 4 1 Command Format The commands consist of a command header that may be followed by numeric parameter values The header consists of a verb a verb and noun or a verb noun and modifier each separated by underscores The first four letters of a word in a command will always be enough to uniquely identify that word when composing commands for the instrument For example the command ENABLE_GAIN_STABILIZATION can be abbreviated to ENAB_GAIN_STAB Numeric parameters are unsigned integer numbers that follow the command header separated by one or more spaces Specific commands require multiple parameters separated by commas that specify numeric quantities related to the operation of the MCB such as live time or conversion gain The command SET_WINDOW 0 8192 has two parameters 0 and 8192 which set the window of interest to start at channel 0 and continue for 8192 channels Some parameters are optional and are delimited by square brackets in the command prototype line to distinguish them from mandatory parameters e g SET_WINDOW start length Com mands with optional parameters can be sent to the MCB without the optional parameters in which case the instrument behavior will be explained in the command description 4 2 Error Cod
25. parallel noise and the FET current series noise The trapezoidal filter is essentially inde pendent of dc offsets since the averaging and subtracting removes the dc component of the signal Unfortunately it is just as sen sitive as analog filters to slowly varying signals such as those produced in micro phonic noise Figure 2 shows the output of the trapezoidal filter is equal to the slope of the baseline signal multiplied by the full width at half maximum FWHM of the trapezoid If a step pulse were to be measured on such a base line the filter output value would be too great by an error equal to the difference between the average values Al and A2 Since the microphonic noise component in a signal is approximately a sine wave as illus trated in Fig 3 the error induced can be positive negative or zero This error signal adds to the width of the spectral lines appearing as degraded resolution performance from the detector and can in many cases be a dominant noise source especially at lower energies Figure 3 Example of Weighting Function Output Resulting from the Positive Slope Due to Low Frequency Noise shown as a sine wave 794380D 0914 1 INTRODUCTION The ORTEC LFR filter removes most of the microphonic noise by estimating the microphonic induced error signal on a pulse by pulse basis and subtracting the estimated error signal from the trapezoid output As noted above the error signal is pr
26. 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 lt CR gt Maximum count was found in channel 0 or no ROI channels were found 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 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 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_RENH Reports if Resolution Enhancer mode is enabled 82 794380D 0914 4 FIRMWA
27. the detector To support older detectors a detector interface module DIM with 12 inch leads connect the detector and DSPEC Pro providing HV bias and control The leads are as follows 9 pin D preamplifier power cable Analog In Shutdown In Bias Out Inhibit In 48 794380D 0914 3 SPECIFICATIONS The DSPEC Pro uses the following DIMs e DIM POSGE For any non SMART 1 positive bias HPGe detector includes leads with mating connectors for existing detector cabling 500 V to 5000 V e DIM NEGGE For any non SMART 1 negative bias HPGe detector includes leads with mating connectors for existing detector cabling 500 V to 5000 V DIM POSNAI For any positive bias Nal detector includes leads with mating connectors for existing detector cabling 100 V to 1800V 300 uA e DIM 296 For any positive bias Nal detector includes Model 296 ScintiPack tube base preamplifier bias supply for Nal detectors with 14 pin 10 stage photo multiplier tubes 0 V to 1200 kV In all cases except the DIM 296 the bias voltage setting and shutdown polarity are set via MAESTRO or other CONNECTIONS software The SMART 1 detector provides detector state of health information as discussed above and in Section 1 7 3 3 Feature Mask Bits The following table describes the feature bits from the SHOW_FEATURES command discussed on page 74 If the feature is supported in the DSPEC Pro the bit is set to 1 if the feature is not supported the b
28. 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 0 with the INITIALIZE_ZERO_ STABILIZATION 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 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 chan nels 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 71 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SHOW_ACTIVE Returns
29. 01000036 lt CR gt Date reported as Jan 1 2000 N031012087056 lt CR gt Date reported as Dec 31 2087 SHOW_DELAY_COLLECTION Shows the width of the PUR signal setting See also SET_DELAY_ COLLECTION Responses DEL_COLL 0000000000001 6 73 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 SHOW_DET_SNUM This command responds with the detector serial number stored in the SMART 1 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_DEVICE Shows the currently selected device Always 1 for DSPEC Pro SHOW_DISPLAY Not used included for backward compatibility SHOW_ETP Reports if Enhanced Throughput Mode is enabled Responses IF Enhanced Throughput Mode disabled IT Enhanced Throughput Mode enabled SHOW_FEATURES Responds with four 32 bit masks indicating which features are present in the MCB See Appendix 3 3 for a complete description of each bit in the mask Example Response FEATURES 02285062207 02014941185 00000000000 00000000000 SHOW_GAIN_ADJUST Returns the gain stabilizer amplifier setting SHOW_GAIN_CHANNEL Reports the current center channel for the stabilizer gain peak See also SET_GAIN_CHANN
30. 1 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Bit 8 92 Description Security Power Comment At the start of the acquisition the DSPEC Pro queries the SMART 1 detector for its serial number The DSPEC Pro then writes a random number to the detector At the end of the acquisi tion both numbers are read from the detector and compared to the original values If there is a mismatch the Security SOH bit is set Set if the power fails during an acquisition APPENDIX B LIST MODE IN THE DSPEC PRO The DSPEC Pro is equipped with List Mode which streams spectroscopy data directly to the computer event by event without the data dead periods associated with the acquire store clear restart cycle of standard spectrum acquisition MAESTRO v7 supports our List Mode MCBs with menu and toolbar commands as well as commands in our automated JOB streams See the MAESTRO user manual for detailed information This appendix provides details about the List Mode that will enable experienced programmers using the ORTEC CONNECTIONS Programmer s Toolkit with Microsoft ActiveX Controls to write custom software applications for acquiring and saving List Mode data For additional information see http www ortec online com Solutions applications software aspx tab 2 B 1 List Mode Data In List Mode each detectable event that would normally be histogrammed as a spectrum is sent to the computer in
31. 337 65 053 ee Ades ie bedg he ey beige pes 42 2d TTOUDIESHOOUNE seoor a aE dn Bas ce utnes eh N BA aaa lee mae E aay 43 2 5 1 MAESTRO Does Not Connect with the DSPEC Pro 43 SPECIFICATIONS eoe i sibs a aes oops Gee Re ES Dany BD aoe ees 45 3 PY S PEC PRO ig oe og A rae Ea aap aease ac Apt Meas teal Raa aioe taps a EE aA 45 3 1 1 Electrical and Mechanical 2 Sssia dasioee edcie hs Rey CEO eee eae YER ER ees 47 Oeil COMNCCIOUS 22s ol wood eae ee ae mae ake wake kT eae ete EELE E REPS 48 3 2 HPGe High Voltage Detector Interface Modules 0 0 00 e eee ee 48 3 0 Feature MASK BUS 2 3 9 etters see eee wey ety eee ey ee CRBS SERS eae ay woes 49 FIRMWARE COMMANDS AND RESPONSES 00 0 e eee eee eee ees 53 AN A OMAN FOrma t aeea a ary a ree En a EEA A A E KEEA ee AaS 53 A ass Error OC S septa ct bik e R OE a S E PRC EG Oh RL EA ET Hee OND O AR 53 4 2 1 Dollar Response Records es ais ean deacon emt Wedel see ee eR eR RR ERE RS 54 ADs MOB Commands sorore eao E ete dea pitta da ew made ON Pe Eee 55 794380D 0914 TABLE OF CONTENTS APPENDIX A STATE OF HEALTH BIT DEFINITIONS 02000002 91 APPENDIX B LIST MODE IN THE DSPEC PRO 0 eee eens 93 Bal List Mode Data serere aronet Beek eee eRe nd Ce P E we eee Ee BOER ER ERE 93 B 1 1 Spectrometer Data Format cag Seiuccte tacondseed alanec astd esena bandanas mai traarae 93 INDEX A EE Gash son alas Ono Ree me Aa ee es Bie a eek mod d
32. 37 20 h 13 min 37 s 85 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SHOW_TIME_ETP Returns the current Enhanced Throughput Mode protection time Response TIME_ETP 0000000000012 8 Protection time is set to 12 8 us SHOW_TIME_START Reports the time of the last START command in the form Nhhhmmmsssccc lt CR gt 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_TRIGGER Tells whether the trigger is enabled or disabled See also ENABLE_TRIGGER Responses IF Trigger disabled IT Trigger enabled SHOW_TRIGGER_POLARITY This returns the polarity setting of the input trigger for the sample changer 1 means the trigger is positive edged and triggers on a low to high transition 0 means it is negative edge triggered and triggers on a high to low transition See also TRIGGER ENABLE_ TRIGGER DISABLE_TRIGGER SHOW_TRIGGER and SET_TRIGGER_POLARITY Responses FNEG lt CR gt The HV is set to negative FPOS lt CR gt The HV is set to positive SHOW_TRIGGER_SAMPLE Reports the trigger source in Insight Mode Responses FOLLD LLD is source F1PKD Peak d
33. 6 characters long and can be set to any arbitrary value The id string is intended to uniquely identify the sample being analyzed See also SHOW_ID Examples SET_ID Site 123 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 archi tecture of the DSPEC Pro 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 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 DSPEC Pro during data acquisition See also CLEAR_COUNTER and SHOW_LIVE SET_LIVE_PRESET ticks Sets the live time preset to the specified number of ticks 20 ms tick During data acquisi tion when the live time counter reaches the preset number of ticks the preset is complete and the acquisition is stopped Setting a live time preset to 0 ticks disables t
34. 66 Check this entry if you a O Maca have any ORTEC USB E O digiDART RS232 based instrument except a C DSPEC jr R 232 A E O mcs Pci CO DigiBASE E Local Instrument list lt No instruments found gt M Allow other computers to use this computer s instruments XY Figure 9 Choose USB based instruments If you also have other types of MCBs attached to this computer refer to the installation instruc tions in the corresponding hardware manuals Note that you can install device drivers for other types of instruments later as described in the CONNECTIONS Driver Update Kit instructions 2 2 2 Step 2 Install MAESTRO Install MAESTRO according to the instructions in its User Manual 20 794380D 0914 2 GETTING STARTED 2 2 3 Step 3 Connect the DSPEC Pro to the Computer 1 With the computer powered on connect the DSPEC Pro to the computer s USB port 2 Windows will indicate that the DSPEC Pro has been detected In Windows 8 and 7 the driver will install without a wizard In XP the new hardware installation wizard will open Click Next indicate 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 When this operation is complete you are ready to run the MCB Configuration program so that MAESTRO and other CONNECTIONS software can recognize the DSPEC Pro 2 2 4 Step
35. AMT 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 AMT of the circumstances so that assistance can be provided in making damage claims and in providing replacement equipment if necessary Copyright 2014 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 NOTICE OF PROPRIETARY PROPERTY This document and the information contained in it are the proprietary property of AMETEK Inc It may not be copied or used in any manner nor may any of the information in or upon it be used for any purpose without the express written consent of an authorized agent of AMETEK Inc ADDITIONAL WARRANTY STATEMENT Please note that the DSPEC Pro contains no user serviceable parts Breaking the seal on the case voids your warranty The DSPEC Pro should be opened only by ORTEC authorized service personnel iii iv Intentionally blank TABLE OF CONTENTS Installation page 19 WARRANTY age cg tei S
36. B instruments can be connected to your computer via USB hubs and across the network As an ORTEC CONNECTIONS multichannel buffer MCB DSPEC Pro works in both standalone and networked configurations Low Frequency Rejector LFR Filter Uniquely designed for mechanically cooled HPGe detectors our Low Frequency Rejector digital filter surpasses all signal processing methods for reducing the effects of microphonics ground loops and virtually all other sources of periodic noise for HPGe and Nal T1 spectrometry Zero Dead Time Correction The DSPEC Pro features our innovative ZDT mode of opera tion an alternative to the classical extended live time clock The ZDT method produces accu rate results in all situations and completely overcomes some of the shortcomings of extended live time methods Moreover the new ZDT method overcomes some limitations in previous loss free dead time correction methods Most notably the ZDT mode does not require any manual adjustments and is capable of computing the statistical uncertainty of the corrected spectrum Single Cable Connection to Detectors DSPEC Pro uses the unique ORTEC Detector Interface Module DIM for single cable connection between the DSPEC Pro and the detector The DIM is designed to supply bias close to the detector so the cable carries only signal and low voltage power no longer is high voltage bias and its associated dangers carried over long distances SMART 1 Su
37. CR gt List mode FSAM lt CR gt Sample mode InSight SHOW_MODE_ZDT Reports the current ZDT mode See SET_MODE_ZDT Responses MODE_ZDT 00000 Mode 0 selected normal and corrected MODE_ZDT 00001 Mode selected error and corrected SHOW_MONI_LABEL num Returns with an ASCII string label designation for the state of health parameter for num SHOW_MONI_ MAX Returns with the number of state of health values available for viewing SHOW_MONI VALUE num Returns with an ASCII representation of the value for the state of health parameter SHOW_NAI Indicates whether ENABLE_NAT 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 the SHOW_ROI command SHOW_NEXT reports the next continuous group of channels that have the ROI flag set The response is of the form 80 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES Dsssssnnnnnccc lt CR gt 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 l
38. Clears data and resets acquisition in List Mode The response is the same as the CLEAR command CLEAR_MDA_PRESET Clears all MCA preset values This command is used to quickly clear the list of MDA preset values CLEAR_PRESETS The live time true time ROI integral ROI peak and overflow presets are all set to zero disabled 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 CLOSE_FILE_FLASH crc No function in the DSPEC Pro included for backward compatibility COMP No function in the DSPEC Pro included for backward compatibility DISABLE_BLRE_AUTOMATIC Disables the automatic determination of baseline restorer time constant See also ENABLE __ BLRE_AUTOMATIC SET_BLRE and SHOW_BLRE 56 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES DISABLE_ETP Returns the DSPEC Pro to normal operation if in Enhanced Throughput ETP mode See also ENABLE_ETP SHOW_ETP SET_TIME_ETP LIST_TIME_ETP and SHOW_TIME_ETP 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 N
39. 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 DSPEC jr 2 0 DSPEC Pro Selectable HV rise time SET SHOW LIST_HV_RISE SBS 60 Monitor command support SHOW_MONI_MAX LABEL VALUE 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 SET SHOW_VIEW in MCBs with Dual Port Memory or printer port interfaces LIST_VIEW in all MCBs Connected to MCB via RS 232 slow port No SET_HV_POSI SET_ HV_NEGA ENA_NAT and DIS_NAI Low Frequency Rejector ENA DIS SHOW_LFR Resolution Enhancer ENA DIS SH_RENHANCER SET SHOW_RETABLE idx val SET_MODE_RELIST for Resolution Enhancer List Mode Readable Sample mode time per channel SH_TIME_ SAMPLE Adjustable Sample mode time per channel SET LIST_TIME_SAMPLE List Mode data streamed and formatted as in digiBASE Supports ETP mode ENA DIS SHOW_ETP List Mode data streamed and formatted as in DSPEC PRO SET SHOW LIST_PZ using floating point microseconds 4 FIRMWARE COMMANDS AND RESPONSES Most software communication with the DSPEC Pro takes place through the CONNECTIONS soft ware layer CONNECTIONS is used by all ORTEC software and can be accessed for other software development with
40. EL 74 794380D 0914 Responses C00000087 lt CR gt C00002089 lt CR gt C16382107 lt CR gt SHOW_GAIN_COARSE 4 FIRMWARE COMMANDS AND RESPONSES Gain channel has not been set Gain channel is channel 2 lowest possible channel Gain channel is channel 16382 highest possible channel Returns the coarse gain for the DSPEC Pro 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 C00002089 lt CR gt C00004091 lt CR gt C00008095 lt CR gt C00016094 lt CR gt C00032092 lt CR gt SHOW_GAIN_CONVERSION Coarse gain reported as 1 Coarse gain reported as 2 Coarse gain reported as 4 Coarse gain reported as 8 Coarse gain reported as 16 Coarse gain reported as 32 This command returns the conversion gain Responses C00512095 lt CR gt C01024094 lt CR gt C02048101 lt CR gt C04096106 lt CR gt C08192107 lt CR gt C16384109 lt CR gt SHOW_GAIN_FINE Conversion gain reported as 512 channels Conversion gain reported as 1024 channels Conversion gain reported as 2048 channels Conversion gain reported as 4096 channels Conversion gain reported as 8192 channels Conversion gain reported as 16384 channels Returns the current fine gain setting See SET_GAIN_FINE Sample Response GAIN
41. GGER DISABLE_TRIGGER SHOW_TRIGGER and SHOW_TRIGGER_POLARITY 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 DSPEC Pro during data acquisition See also CLEAR_COUNTER and SHOW_TRUE 70 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES SET_TRUE_PRESET ticks Sets the true time preset to the specified number of ticks 20 ms tick During data acquisi tion 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 preset See also CLEAR_PRESETS and SHOW_TRUE_PRESET 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 chan nels 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 SET_ZERO_ADJUSTMENT value Sets the
42. HOW_GAIN_ADJUSTMENT command See also SET_GAIN_ ADJUSTMENT ENABLE_GAIN_ STABILIZATION and DISABLE_GAIN_ STABILIZATION 60 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES 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 See also SET_BLRE Response BLRE 10 0 100 0 10 100 Legal settings are 10 0 to 100 0 in steps of 1 LIST_CORR_FLAT Lists the valid settings of the flattop width See also SET_CORR_FLAT Response CORR_FLAT 1 0 992 0 255 Legal settings are from 1 to 0 992 in 255 0 1 256 steps LIST_DISPLAY Not used by the DSPEC Pro included for backward compatibility LIST_GAIN_COARSE Lists the valid coarse gain settings Response GAIN_COAR 1 2 4 8 16 32 LIST_GAIN_CONV Lists legal conversion gain settings Response GAIN_CONV 512 1024 2048 4096 8192 16384 LIST_GAIN_FINE Lists the valid fine gain settings Response GAIN_FINE 0 45 1 0 88437 196607 0 45 to 1 in 108171 steps LIST_HV Lists the valid high voltage settings Response HV 0 5000 0 5000 0 to 5000 in 5000 steps 61 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 LIST_MODE_ZDT Reports the legal ZDT mode settings Each item i
43. If it is necessary to accept higher counting rates the rise fall times must be shortened accordingly For this case the DSPEC Pro includes a flattop feature for the filter that can eliminate the resolution broadening caused by ballistic deficit Instead of a symmetrical triangle with a sharp point at the 8 794380D 0914 1 INTRODUCTION peak amplitude the rising and falling edges are separated by a flattop to form a trapezoid The width of the flattop is adjusted to be long enough to match the longest charge collection time for the detector employed This allows time for the longer charge collection pulses to reach the same maximum pulse amplitude as the faster charge collection pulses from gamma rays of the same energy Consequently the effect of ballistic deficit is reduced and the energy resolution is dramatically improved at these short pulse widths Note that the selection of shorter pulse widths inevitably degrades the signal to noise ratio com pared to the optimum achieved at longer pulse widths Thus operating at shorter pulse widths will compromise the energy resolution of low energy gamma rays for which the preamplifier noise makes a significant contribution to the energy resolution The signal to noise degradation is independent of the ballistic deficit effect The flattop and other shaping controls are on the Amplifier 2 tab under Acquire MCB Proper ties see Section 2 3 2 for a more detailed discussion 1 6 Zero Dead T
44. LL or CLEAR_HV_ HEALTH At the end of the acquisition the DSPEC Pro reads the SOH and if any bit is set displays a warning message If no bits are set no message is displayed this means 15 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 there was no problem during the acquisition The SOH status is saved with the spectral data in the SPC file as part of the QA data MAESTRO GammaVision and other ORTEC programs can monitor the status of the SOH bit for the current spectrum on the Status tab under Acquire MCB Properties In addition user developed programs may read and write the SOH register Chapter 4 provides the commands for reading and interpreting the SOH settings see Appendix A for a table of SOH bit definitions 1 8 Host Computer and Software Requirements The DSPEC Pro is completely computer controlled and can be operated with any suitable ORTEC CONNECTIONS software including the supplied MAESTRO MCA Emulation Software A65 BW communicating via the supplied version of CONNECTIONS The current version of MAESTRO runs under Microsoft Windows 8 7 XP Professional SP3 1 9 About this Manual This manual describes the DSPEC Pro tells how to connect it in a complete spectroscopy sys tem gives instructions on configuring the hardware settings such as high voltage presets and gain and supplies the hardware commands and responses Complete details on using the con trol software are in the
45. N_STABILIZATION and INITIALIZE_GAIN_STABILIZATION ENABLE_HV Turns on the high voltage enable output of the DSPEC Pro See also DISABLE_HV and SHOW_HV ENABLE_HV_DIM Enables the DSPEC Pro to work with a standard DIM e g DIM POSNAI DIM POSGE or DIM NEGGE DIM 296 This command causes the DSPEC Pro to poll the DIM and return state of health information to a controlling program see SHOW_HV_HEALTH command ENABLE_LFR Sets the DSPEC Pro to LFR mode See also DISABLE _LFR and SHOW_LFR ENABLE_NAI Switches the stabilizers to NaI 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 DSPEC Pro 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 DSPEC Pro needs pole zeroing ENABLE_REMOTE No function in the DSPEC Pro included for backward compatibility 59 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D
46. ORTEC 42 794380D 0914 2 GETTING STARTED digital spectrometers operate well above the peak of the throughput curve Operating there allows these instruments to handle an even higher rate of incoming counts but with less data into memory and therefore a longer count time to the same detection limit It is possible to move the peak of the curve to the right more counts to memory with higher input count rate by reducing the pulse rise and fall time thereby trading off resolution for maximum count rate Table 2 is a guide to choosing a count Table 2 Rise Time Selection Guide rate that will ensure that the most efficient operation of your digital spectrometer over Dynamic Range Throughput us the range of anticipated input count rates for your application that is at or below o gt 50000 1250 s8 the throughput peak while achieving the best resolution obtainable from the detector consistent with that requirement Enter the rise time that best matches your dynamic range of count rate note that the available 0 gt 200k 70000 08 rise time settings will vary by instrument 0 gt 220k_ 85000 o6 this chart is a general guide only 0 gt 250k 100000 0 gt 300k 120000 The longest rise time shown in the table is 12 us even though some digital instruments can be set for rise times as long as 23 us If throughput is not an issue because all samples are low rate increasing the rise time beyond
47. ORTEC DSPEC Pro Digital Gamma Ray Spectrometer Hardware User s Manual Printed in U S A ORTEC Part No 794380 0914 Manual Revision D Advanced Measurement Technology Inc AMT WARRANTY AMT warrants that the items will be delivered free from defects in material or workmanship AMT makes no other warranties express or implied and specifically NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE AMT s exclusive liability is limited to repairing or replacing at AMT s option items found by AMT to be defective in workmanship or materials within one year from the date of delivery AMT 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 AMT fails to manufacture or deliver items called for in this agreement or purchase order AMT 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 AMT be liable for special or consequential damages Quality Control Before being approved for shipment each AMT instrument must pass a stringent set of quality control tes
48. PR 005 Calibration source 1714 File Acquire Calculate Services RO Display si ARA CxK Los A 1000 IARAA 0002 DSPR 005 7 Mark Peak Trigger LLD T Single Reset Delay 79 60 E Baseline Restorer Auto EE nS Fast f Slow up 50o Pole Zero Auto 2064 Other Controls ORTEC 11 00 45 4M Wed 10 Jul 02 Marker 50 00 pS Mcb Model No DSPR 002 Figure 15 DSPEC Pro InSight Mode In the Auto trigger mode the display is updated every time a new pulse exceeds the trigger level To keep a single pulse displayed select Single Click Reset to refresh the display to see the next pulse There will usually be one or two pulses in the pipeline that will be displayed before any change entered will be seen If the trigger is turned off the display will be redrawn periodically even if no pulse is there The Delay setting is the time delay between the pulse shown on the display and the trigger level crossing The value of the time delay is shown on the display 28 794380D 0914 2 GETTING STARTED Just as for the PHA mode display the vertical scale can be adjusted with the vertical adjust ments The display can be set to Log mode but the peak shapes do not have a familiar shape in this display The Auto mode will adjust the vertical scale for each pulse The pulse is shown before the amplifier gain has been applied so the relation between channel number and pulse
49. Pro For more security it can save authentication codes written to it and report the code at a later time The authentication code value is replaced with every start command At the end of the acquisition both the serial number and code are read and checked with the values at the start of the acquisition ORTEC SMART 1 HPGe detectors monitor the following conditions 14 Preamplifier 24 and 12 V values read only Preamplifier voltage out of range read only Detector element temperature read only Detector high voltage value read only Detector high voltage state on off Detector overload state read only Detector high voltage shutdown state read only Detector serial number read only Detector authentication code read write 794380D 0914 1 INTRODUCTION 1 7 1 SMART 1 HPGe Detector Construction In the SMART 1 detector the controller and high voltage power supply are contained in a single small module and are permanently attached to the detector endcap The cable is strain relieved and sealed This eliminates the possibility that the detector will suffer severe damage from moisture leaking into high voltage connectors The controller can be positioned in any convenient place It does not interfere with shielding or other mounting hardware 1 7 2 Using Older Detectors For older detectors a detector interface module DIM is used The DIM is a compact size and can be attached directly to the detector itself keep
50. RE COMMANDS AND RESPONSES Responses SIF Resolution Enhancer mode disabled IT Resolution Enhancer mode enabled SHOW_ROI Used in conjunction with the SHOW_NEXT command SHOW_ROI reports the first contin uous group of channels that have the ROI flag set The response is of the form Dsssssnnnnnccc 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 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 SAMPLE Displays the ROI Sample setting See also SET_ROI_SAMPLE Responses C00001088 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 numb
51. RO tab and mark the Resolution Enhancer checkbox 5 Acquire the first training spectrum then record the FWHM for the Am Cd Cs and Co peaks Clear the data acquire another spectrum and record the FWHMs for the target peaks After 2 4 iterations the FWHMs should no longer change appreciably indicating the Resolution Enhancer is trained Save the final spectrum with a name and optional sample description indicating the Resolution Enhancer was used to improve peak resolution 6 The table of adjustments will be stored in the DSPEC Pro s memory and will continue to be used each time you mark the Resolution Enhancer checkbox until retrained NOTE Ifyou change any parameters that affect peak shape you must repeat this training procedure To Turn the Enhancer Off 1 With the Resolution Enhancer checkbox still marked switch to the Stabilizer tab and click the Gain Stabilizer section s Initialize button 2 Return to the Amplifier PRO tab and unmark the Resolution Enhancer box 3 Re optimize 2 3 4 ADC This tab Fig 18 contains the Gate ZDT Mode Conversion Gain Lower Level Discrimi nator and Upper Level Discriminator controls In addition the current real time live time and count rate are monitored at the bottom of the dialog Gate This control allows you to select a positive TTL logic level gating function With gating Off no gating is performed that is all detector signals
52. When you reconnect the DSPEC Pro to the com puter you will have to reselect it from the detector droplist on the Toolbar 2 3 DSPEC Pro MCB Properties in MAESTRO This section discusses the hardware setup dialog you will see within MAESTRO and all other ORTEC CONNECTIONS software e g GammaVision ISOTOPIC when you click Acquire MCB Properties The DSPEC Pro is completely software controlled the MCB Properties dialog contains all of the instrument controls including ADC setup parameters acquisition pre sets amplifier gain adjustments pole zero controls and access to the InSight Virtual Oscillo scope Just move from tab to tab and set your hardware parameters then click 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 computer on the network can modify this value 2 3 1 Amplifier Figure 13 shows the Amplifier tab Properties for DSPR 0008 This tab contains the controls for Gain Baseline Restore Preamp soit r gea lifier Type Input Polarity and Op timize Gain 1 00 Baseline Restore Optimize 0 25 1 00 fauo 4 Start Auto NOTE Be sure that all of the I p Preamplifier Type ea controls on the tabs have T e Resistor Feedbact p Input Polarity been set before c
53. _FINE 000000 70000203 SHOW_GAIN_POLARITY Fine gain is set to 0 7 Returns the polarity of the amplifier input as F records Responses FNEG lt CR gt FPOS lt CR gt The amplifier input is set to negative The amplifier input is set to positive 75 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SHOW_GAIN_STABILIZATION 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 lt CR gt Gain stabilization is currently disabled SHOW_GAIN_WIDTH Reports the current width for the stabilizer gain peak See also SET_GAIN_WIDTH SET_GAIN_CHANNEL and SHOW_GAIN_CHANNEL Responses C00001088 lt CR gt Gain width has not been set C00003089 lt CR gt Gain width is 3 channels lowest possible width C00256100 lt CR gt Gain width is 256 channels highest possible width in Gauss mode 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 o
54. 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 84 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES 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 O normal 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 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 is 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
55. ace and special symbols such as the underscore _ and comma 13 in the prototype line are literal text to be sent to the MCB exactly as they appear Lowercase letters in the prototype line represent numeric values as described in the accompanying text they should not be sent literally to the MCB but should be replaced by an appropriate numeric value In this section the term lt CR gt 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 equi valent to the combination of CLEAR_COUNTER and CLEAR_DATA commands 55 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 CLEAR_ALL This command is equivalent to the combination of CLEAR_COUNTER CLEAR_DATA CLEAR_PRESETS and CLEAR_ROI commands CLEAR COUNTER 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 This command clears the SOH bits in the DIM and does not affect the stored SOH which is reported when the instrument is not acquiring data CLEAR_LIST
56. b The polarity is determined by the DIM or SMART 1 module which also supplies the bias voltage The recommended HV for SMART 1 is displayed on the dialog For other detectors see the detector manual or data sheet for the recommended voltage 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 The HV will not turn on if the detector is sending a remote shutdown or overload signal The Overload indicator means there 35 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 is a bad connection in your system The Shutdown indicator means that either the detector is warm or you have chosen the wrong Shutdown or Source mode To use a Sodium Iodide Detector mark the checkbox This changes the gain and zero stabili zers to operate in a faster mode For the DIM 296 the HV is controlled by the adjustment in the Model 296 and not here 2 3 7 About This tab Fig 21 displays hardware and firmware information about the currently selected DSPEC Pro as well as the data Acquisition Start Time and Sample description In addition the Access field shows whether the MCB is currently locked with a password see the password discus sion in the MAESTRO user manual Read Write indicates that the MCB is unlocked Read Only means it is locked 2 3 8 Status Figure 22 shows the Status tab There are 21 values mo
57. ce does not affect the PHA mode choice The colors are the same as for the PHA mode None No channels are marked in the display PileUpReject The region marked indicates when the PUR circuit has detected pileup and is rejecting the marked pulses NegBLDisc This shows when the negative baseline discriminator has been triggered Typically this signal only marks the TRP reset pulse The signal is used internally in the live time correction baseline restoration and pile up rejection circuits 29 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 BaseLineR This shows when the baseline restorer is actively restoring the baseline PosBLDisc This shows when the positive baseline discriminator has been triggered The signal is used internally in the live time correction baseline restoration and pile up rejection circuits Busy When the DSPEC Pro busy signal is active Busy shows in the Mark box It represents the dead time Gate This shows when the gate signal is present on the gate input connector If the Gate mode on the ADC tab see Fig 18 is set to Off then all regions are marked If the mode is set to Coincidence then the marked region must overlap the pulse peak that is must start before the beginning of the flattop and stop after the end of the flattop for the pulse to be counted If the mode is set to Anticoincidence then the marked region will show the pulses that are accepted That is the rejected p
58. compatibility DISABLE_RENH Returns the DSPEC Pro to normal operation if the Resolution Enhancer is enabled See ENABLE_RENH DISABLE_THRESHOLD_AUTOMATIC DISABLE_THRESHOLD_SAMPLE DISABLE_TRIGGER_SPECIAL No function in the DSPEC Pro included for backward compatibility DISABLE_TRIGGER Disables the data acquisition trigger that was enabled by the ENABLE_TRIGGER command Cancels an ENABLE_TRIGGER_REP if it is issued before the acquisition starts See ENABLE_TRIGGER TRIGGER and SHOW_TRIGGER 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 DISABLE_ZDT Returns the DSPEC Pro to normal operation if in zero dead time ZDT mode See ENABLE_ZDT ENABLE_BLRE AUTOMATIC Enables the automatic determination of baseline restorer time constant See also DISABLE _ BLRE_AUTO SHOW_BLRE and SET_BLRE ENABLE_ETP Sets the DSPEC Pro to Enhanced Throughput ETP mode See also DISABLE_ETP SHOW_ETP SET_TIME_ETP LIST_TIME_ETP and SHOW_TIME_ETP 58 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES ENABLE_GAIN_STABILIZATION Enables the stabilization of the gain peak See also DISABLE_GAIN_STABILIZATION SHOW_GAI
59. d counts for the channels adjacent to the peak start low energy channel L B sum of background counts for the channels adjacent to the peak end high energy channel H n the number of low background points n 1 3 or 5 used n the number of high background points n 1 3 or 5 used The peak area uncertainty is calculated from o Gr 8B where G is the sum of counts from the error spectrum from channels L to H from error spectrum Area from ZDT spectrum error x 100 In our WAN and ISOWAN analysis engines the peak fitting routine fits all the library peaks as singlets to calculate the peak centroid peak start and end channels and peak background A linear background under the peak is assumed during the peak fitting process The error spectrum is always used to calculate the uncertainties of counts whenever needed For example if peak deconvolution is needed the error spectrum is used to find the best fit for the peak background 1 6 4 Choosing a ZDT Mode When the counting rate is essentially constant during the time required to acquire the spectrum the standard mode ZDT Off is the preferred mode only the uncorrected spectrum is col lected and stored in the spectrum file But if the counting rate varies significantly during the measurement time the standard mode will not yield the proper dead time corrected counting rate This can be most easily understood by noting that the unc
60. d is created therefore it represents only 10 ms of external pulses Optionally the external counters can be configured to be a simple level sensitive input In this case the counter value is either 0 or 1 depending on the level of the input at the time the counter word is generated 95 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Intentionally blank 96 Acquisition presets 6 d b 4 56 ach ay ee Ce Baie 39 ADE SUID 38 thai apara cee hae yeh eas 33 AMUCOIMCITENCE 49 5 2d ey ep trana eaea 33 Ballistic deficit and flattop 8 Charge trapping correction 4 COIMCIIENCE srt oaea Spc erat eh aaah Cast are 33 Count rales i eid tt ian rA cate ah dae Sie 25 27 Dead UME yas Sete eles o Oath a tte anA 39 DSPEC PRO PO Setpa ouais Pues ot Be Sel 33 amplifier settings 3 645 ata densa kias 24 26 ANLCOMCIPENCE 33 ay cae hese ae ea 33 COMCIGENCE cack taba agen thag tunel ack Cys 33 Enhanced throughput mode 31 high voltage setup 04 35 MSieht mode a tab oa bata dena aA 27 liyetime preste cease at iana ab cys 39 low frequency rejector LFR 31 lower level discriminator 34 MDA Preset 4 4 bien a ea dena iaa 40 OPUS seian ose Re ate ak ae 25 OVETIOW prESEt 2 3 oye ate eae aai 40 r al time PRESCU seed oyys s ea ay nh end gx 39 Resolution Enhancer 32 ROI integral preset 3 eine pea ay sae Cebu 40
61. e LTC spectrum can be used to determine exactly how many pulses at any energy were pro cessed by the spectrometer The corrected spectrum gives the best estimate of the total counts that would have been in the peak if the system were free of dead time effects The uncertainty spectrum can be used to calculate the counting uncertainty channel by channel in the corrected spectrum Patent number 6 327 549 10 794380D 0914 1 INTRODUCTION NOTE When the spectrometer is placed in ZDT mode the throughput of the instrument is reduced somewhat as extra processing must be done on the spectrum therefore if the gamma ray flux is not changing as a function of time but absolute highest throughput is desirable you might wish to store only the LTC spectrum in the MCB memory 1 6 2 NORM_CORR ZDT and Uncorrected Spectra Stored When the ZDT mode is set to NORM_CORR the two spectra stored are the LTC spectrum and the ZDT spectrum corrected for the dead time losses real time only Unfortunately in the analysis of the ZDT spectrum the uncertainty of the measurement cannot be determined using either spectrum NOTE This mode is not useful for quantitative analysis if the counting rate varies significantly during the measurement time particularly if the user desires an accurate counting rate and standard deviation calculation When you select the NORM_CORR mode the spectroscopy software ignores the ZDT spectrum and analyzes the LTC spectrum a
62. e efficiency component in the CorrectionFactor is set to 1 0 the preset field is labeled Correction instead of MDA and the preset is based on counting activity cA instead of becquerels You can enter the MDA preset either in counts or corrected for factors such as sample volume attenuation or calculated efficiency For example if you manually calcu late the efficiency for a peak you can enter a corrected MDA target value by multi plying the desired MDA value times the calculated efficiency and entering the product as the Correction 41 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 To add an MDA preset enter the preset value in the MDA or Correction field select the Nuclide and Energy enter the desired values for coefficients a b and c then click Add New To edit an existing preset click to highlight it in the table This will load its Nuclide Energy and coefficients in the lower sections of the dialog Change as needed then click Update To remove a preset click to highlight it in the table then click Delete IMPORTANT These MDA presets are not dynamically calculated Each time you add an MDA preset to this table its CorrectionFactor value is calculated and stored in the MCB s memory If you then load a different library change the efficiency calibration or change the system geometry the spectroscopy application will not update the existing CorrectionFactors and your MDA presets may no
63. e time constant can be manually set on the InSight display see the discussion beginning on page 27 You can view the time when the baseline restorer is active on the InSight display as a Mark region see the discussion on Marks p 29 In the automatic mode the current value is shown on the InSight sidebar Fig 15 For a low count rate system the value will remain at about 90 Preamplifier Type Choose Transistor Reset or Resistive Feedback Your choice will depend on the preamplifier supplied with the germanium detector being used Optimize The DSPEC Pro is equipped with both automatic pole zero logic and automatic flattop logic The Start Auto optimize button uses these features to automatically choose the best pole zero and flattop tilt settings Note that if you select Transistor Reset as the preamp lifier type the optimization routine does not perform the pole zero During optimization pole zeroes are performed for several rise time values and the DSPEC Pro cycles 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 DSPEC Pro you do not have to repeat optimization for each possible rise time Optimization requires a source with sufficient activity to register between 800 cps and 5000 cps Arrange the detector in its final configuration Unmark the LFR checkbox on the Amplifier PRO tab you cannot optimize with LFR mode enabl
64. ea e pe aes ates tag oe A ee Sore ere ee ee eet ii ADDITIONAL WARRANTY STATEMENT 0 0 e cece eee eens iii Safety Instructions and Symbols ssesusuesaaeun eenen eere Vili Cleaning INStr ctionS 433 Asis cue ylides CE Nee te Neha ae eos E Meh ESE N Vili Mi INTRODUCTION e td eee tg ent ated og RA baste eee ras Samora iene a argue ena ae Aa Ora cy ah gh 1 kle Whiythe DSPEGC PrO thenant ae ee Ee eee ae ee ee ee ee 1 1 1 1 DSPEC Pro Technologies os cnea iq teen s aes astute neat a eens aes 1 1 1 2 Proven Technologies of the DSPEC Family 02 000000 2 1 2 Enhanced Throughput Mode v2 aces cred ain Ant hataG nee he ale hese Maw ae Rad 3 1 3 Resolution Enhancement Mode Corrects for Charge Trapping 4 1 4 The Low Frequency Rejector LFR Filter 0 0 0 0 cece ene 5 1 5 Ballistic Deficit and Adjusting the Flattop Duration 0000000 8 1 6 Zero W ead lime ZDT Modo ee creneee eranmi Bie ohare Beg Rasheed ek mendes 9 1 6 1 Off Uncorrected Spectrum Only 6 66 0 655 060 ccs ce eee cde ween ees 10 1 6 2 NORM_CORR ZDT and Uncorrected Spectra Stored 11 1 6 3 CORR_ERR ZDT and Error Spectra Stored 20 00055 11 1 6 4 Choosing a ZDT Modes se enene tee te dee Ve annerer 12 1 6 4 1 The NORM_CORR Diagnostic Mode 00055 13 164 2 To S mmari Ze coe cata hae Aenea ee eek Cee Mee re aes 13 1 0 4 3 Mo
65. eaks will not be marked Simply put in all modes the accepted peaks are marked Peak This is the peak detect pulse It indicates when the peak detect circuit has detected a valid pulse The Mark occurs about 1 5 us after the pulse maximum on the display On the lower right of the InSight display are the shaping parameter controls The controls are split into two groups and the other controls button switches between them One group includes Rise Time Flattop Tilt and the Optimize button 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 Tilt can be positive or negative Choosing a positive value results in a flattop that slopes down ward choosing a negative value gives an upward slope Alternatively Optimize can set the tilt value automatically This 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 button also automatically adjusts the pole zero setting 2 3 3 Amplifier PRO This tab Fig 17 contains the controls for the Low Frequency Rejector LFR filter Resolu tion Enhancer and Enhanced Throughp
66. ectra are stored in the resulting spectrum file Note that the counts in the ZDT spectrum must be divided by the elapsed REAL time to compute the dead time corrected counting rate It is important to note that the standard deviation in the Nzpr counts in a gamma ray peak in the ZDT spectrum is not N Instead the standard devia ZDT tion is obtained from the N counts in the same peak ROI in the accompanying error spectrum The standard deviation in this case is N pgg And the standard deviation in the computed count ing rate N Real Time is Live Time ZDT Nerr 1 6 4 1 The NORM_CORR Diagnostic Mode Why is there a NORM_CORR mode and why should you avoid using it This mode simul taneously collects the ZDT spectrum and the conventional uncorrected spectrum It is useful for demonstrating that the counts in the uncorrected spectrum divided by the live time is the same counting rate as the counts in the ZDT spectrum divided by the real time in the special case of constant counting rate Because the error spectrum is not collected in NORM_CORR mode the standard deviation in the ZDT counts cannot be calculated if the counting rate is varying The spectroscopy software provides some protection for users if the ZDT LTC mode is inadver tently selected In this case the software ignores the ZDT spectrum and presumes you intended to use the uncorrected spectrum in a constant counting rate application 1 6 4 2 To Summarize
67. ed see Section 2 3 3 turn on the HV so the instrument is processing pulses then place the source on or near the detector endcap A count Patent number 5 821 533 25 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 rate guidance message on the lower left of the Amplifier page will help you position the source to deliver the correct count rate for optimization You may also right click in the spectrum window and select Input Count Rate from the context menu to view the count rate meter The Start Auto optimization button will remain disabled gray until the count rate is suitable Click it to start A series of short beeps indicates optimization is in progress When optimizing is complete the beeping will stop The process can take from 1 to 10 minutes depending on count rate but typi cally takes 5 minutes NOTE As with any system the DSPEC Pro should be optimized any time the detector is replaced or 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 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 2 3 2 Amplifier 2 Figure 14 shows the Amp
68. ed 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_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 coeffficients a b and c used for the MDA calculation See SET_MDA_COEF 79 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 SHOW_MODE Reports the current mode of operation PHA List or Sample InSight Virtual Oscillo scope See also SET_ MODE_PHA and SET_MODE_SAMPLE Responses FPHA lt CR gt PHA mode FLIS lt
69. ent occurred 200 ns relative to the beginning of the acquisition LT Words are created by the spectrometer at the same time as are RT Words The 30 bit live time stamp represents the ADC live seconds since the beginning of the acquisition or since the last CLEAR command By calculating the relative change in live time between any two LT Words in a list mode stream you can calculate the live time for a given block of data 10 ms The ADC CRM word contains the value of the spectrometer s count rate meter and is generated at the same time as the RT and LT words 1 e it always appears next to these words in the list mode data stream The count rate meter is incremented each time the ADC fast channel detects a pulse Since many pulses may be rejected before one is converted into an ADC event this number is not the simple sum of the ADC events over the past 10 ms instead it represents the true input count rate as well as it can be measured by the instrument Note that this value is zeroed after an ADC CRM word is created therefore it represents only 10 ms of ADC input counts The Ext Counter words contain the value of the external input pulse counters and are generated at the same time as the RT and LT words The external pulse counters count the positive pulses at the external input of the spectrometer Note that the external inputs must stay high for at least AO ns for the pulse to be counted These counters are zeroed after an Ext Counter wor
70. er Always 1 for the DSPEC Pro SHOW_SHAPE_CUSP Not used by the DSPEC Pro included for backward compatibility 83 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 Shows the type of HV shutdown selected Responses FORT ORTEC mode selected FTTL TTL mode selected FSM1 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 DSPEC Pro Response F100 Serial number 100 SHOW_STATUS Returns system status information in the following format SMI ttttttttttaaaaahhhhhccc lt CR gt where IHIIHI 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
71. er specified MDA nuclides reach the needed value Presets are expressed in Bq and are evaluated every 40 seconds The detector must be calibrated for energy in all spectroscopy applications and for efficiency in all applications but MAESTRO The MDA presets are implemented in the MCB i e the entries you make on this screen are saved in the MCB memory and have no direct link to MDA methods selected in the analysis options for applications such as GammaVision ScintiVision ISOTOPIC etc The MDA preset calculation uses the following formula 40 794380D 0914 2 GETTING STARTED r Properties for DSPR 0008 Amplifier Amplifier2 AmplifierPRO ADC Stabilizer High Voltage About Status Presets MDA Preset MDA Preset Nuclide Energy MDA Preset Coefficients Correction c 4 10 000000 Nuclide Pu 238 B 10 000000 Energy ke C 0 000000 Figure 24 DSPEC Pro MDA Preset Tab MDA at b c Counts Live time CorrectionFactor where a b and c are determined by the MDA criteria you choose Counts is the gross counts in an ROI that is 2 5x FWHM around the target peak energy Live time is evaluated in 40 second intervals for the MDA presets CorrectionFactor is the product of the calibration efficiency at the specified peak energy and the peak s branching ratio yield as listed in the working active library NOTE MAESTRO does not support efficiency calibration Th
72. ercent 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 Note that MAESTRO calculates this preset once per 40 seconds Therefore the software will continue data acquisition up to 40 seconds after the preset has been reached and the uncertainty achieved for a high count rate sample may be lower than the preset value Use the Start Channel and Width fields to enter the channel limits directly or click 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 calcu lation 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 Marking the Overflow checkbox terminates acquisition when data in any channel exceeds 2 1 gt 2x10 counts 2 3 10 MDA Preset The MDA preset Fig 24 can monitor up to 20 nuclides at one time and stops data collection when the values of the minimum detectable activity MDA for all of the us
73. es On each completion of the command the MCB returns a macro error code and micro error code 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 O meaning no error In case of error condition you can use the MIOGetLastError DLL interface or GetErrMajor GetErrMinor ActiveX control interface Macro error codes 0 Success S O Power up just occurred Battery backed data lost 53 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 isi 132 Invalid Command For macro code 129 syntax error or 131 execution error the following apply 129 Micro error codes Success Input already started stopped 2 Preset already exceeded Input not started stopped Parameter was rounded for decimal numbers No sample data available 4 2 1 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 54 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES unsigned checksum of all characters on the record up to but not including the checksu
74. etect is source F2RANDOM Trigger happens randomly F3Gate Gate Input triggers the waveform SHOW_TRIGGER_SPECIAL Not used included for backward compatibility 86 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES SHOW_TRUE Reports the contents of the true time counter in units of 20 ms 50 ticks s See also CLEAR_COUNTER 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 lt CR gt 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 lt CR gt True time preset reported 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
75. eup 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 LIST_ULSCA Device supports the MDA preset Software selectable ADC type Matchmaker Has ability to daisy chain MCBs DART ZDT functions available DSPEC Plus DSPEC jr DSPEC jr 2 0 DSPEC Pro 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 No Peak Preset feature M CA and OASIS Programmable pulser OASIS Programmable Vacuum HV interlock OASIS 51 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Bit 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 52 Meaning Programmable
76. gen erated The electrons and holes are swept to the detector electrodes by the electric field inside the detector If all the electrons and holes travel the complete path to the detector electrodes a signal is produced proportional to the energy deposited in the detector by the gamma ray If some of the electrons or holes do not reach the electrodes the signal produced will be smaller than expected The process of interrupting the movement of an electron or hole is referred to as charge trapping If charge trapping did not occur the resolution of a reasonably low noise germanium detector for the 1 33 MeV gamma ray from Co would be about 1 5 keV FWHM Real detectors typi cally have a resolution of 1 8 to 2 2 keV FWHM ORTEC s Charge Trapping Corrector CTC helps reduce this energy resolution loss caused by charge trapping yielding the DSPEC Pro s Resolution Enhancer Mode The controls are accessed via the Acquire MCB Properties command in the accompanying MAESTRO Multichannel Analyzer Emulation Software A65 BW and other ORTEC CONNECTIONS applications Charge trapping is caused by various defects and impurities in the germanium crystal and thus varies from detector to detector The amount of charge lost due to trapping also depends on the distance the charge carrier electron or hole has to move to reach the collecting electrode If the carrier must travel a long distance it is more likely to be trapped If some of the charge
77. he DSPEC Pro included for backward compatibility TRIGGER Starts data acquisition if the trigger has been enabled ENABLE_TRIGGER VERIFY_CORR_FLAT VERIFY_SHAP_FLAT VERIFY_SHAP_RISE These test the argument against the list of valid settings and return true if valid 90 APPENDIX A STATE OF HEALTH BIT DEFINITIONS Following are descriptions of the SOH bit To monitor these within MAESTRO click Acquire MCB Properties then on the Status tab see Fig 26 Bit Aa N r Properties for DSPR 0008 Amplifier Amplifier2 AmplfierPRO ADC Stabilizer High Voltage About Status Presets MDA Preset Ok DIM 24V State Of Health OK DIM 12V State Of Health OK DIM 1 State Of Health OK DIM 24V State Of Health OK or Temperature State Of Health OK Description 24V 12V 12 V 24V Figure 26 The SOH Status Tab within MAESTRO Comment The first four bits monitor the voltages coming from the DSPEC Pro If one of these values varies by more than 2 V the corre sponding bit is set Temperature Set if the detector temperature increases and shuts down the HV HV voltage Overload Shutdown therefore the SHUTDOWN bit will also be set Set if the high voltage deviates by more than 300 V from the value you entered in MAESTRO Set if the preamplifier overloads for more than about 4 0 seconds Set if the preamplifier shuts down for any reason 9
78. he flattop correction value See also SET_CORR_FLAT Responses CORR_FLAT 000000000000000 72 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES 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 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 to 031 month as a 3 digit integer number from 001 to 012 and year as a 3 digit integer number from 000 to 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 N0010
79. he output pulse begins to rise as soon as the gamma ray is detected It continues to rise until it reaches a peak amplitude at a time specified by the currently selected rise fall time this is the Rise Time parameter entered on the Amplifier 2 tab under Acquire MCB Properties see Section 2 3 2 Beyond this peak amplitude time the pulse falls back to the baseline to allow a subsequent gamma ray to be processed If all the charge has not been collected by the detector by the desig nated time for peak amplitude there will be a deficit in the measured peak amplitude and a broadening of the pulse width The deficit in amplitude is called the ballistic deficit Obviously events that result in a faster charge collection time will suffer less deficit and less increase in pulse width than those yielding a slower charge collection time even though the deposited energy was identical Thus the ballistic deficit resulting from variable charge collection times broadens the energy resolution for that gamma ray If the longest charge collection time is negligible compared to the rise time of the filter pulse the ballistic deficit will be imperceptible and the energy resolution will not be degraded Thus at the 10 to 20 us rise times typically selected for optimum signal to noise ratio i e minimum peak FWHM at low energies the ballistic deficit problem can be ignored Long rise times create higher dead times and depress the maximum counting rate limit
80. he preset See also CLEAR_PRESETS and SHOW_LIVE_PRESET 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 following condition to be met 66 794380D 0914 4 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 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 com patibility software that only supports the one nuclide MDA method implemented in some MCBs SET MODE
81. height is not fixed The horizontal scale extends from 16 to 256 channels The display is expanded around the marker position which means that in some cases the peak will disappear from the display when it is expanded The display can be switched from the DSPEC Pro to another detector or the buffer In this case the other detector will be shown in the mode selected for it The buffer will always be shown in PHA mode The display will return to the InSight mode when you return to the first DSPEC Pro If you exit the program with the DSPEC Pro in InSight mode it will be in InSight mode on the next startup The display can include a Mark to indicate one of the other signals shown lt none gt g in Fig 16 The Mark is a solid color region displayed similarly to that of an i l ROI in the spectrum This Mark can be used to set the timing for the gate Tir i eei pulse It can also be used to set the shaping times and flattop parameters to BaseLineR get the best performance For example suppose you want to get the best PosBLDisc resolution at the highest throughput possible By viewing the pulses and the ser pileup reject marker you can increase or decrease the rise time to obtain a Peak minimum of pileup reject pulses Figure 16 Mark Display Selection Mark Types For the Mark choose either points or filled to the zero line display This is controlled by the selection in the Display Preferences menu item That choi
82. his sets the baseline restorer time constant to the value baseline Baseline is in micro seconds 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 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 chan nels 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 SET_DATA_APPLICATION string1 string2 This is used to store information in the DSPEC Pro internal memory that can be used by other programs such as sample descriptions and energy calibrations CONNECTIONS uses 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 cur rent 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 yea
83. ied 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 DSPEC Pro 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_PRESFT 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 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_ROIL 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_ROILSAMPLE num Selects which control 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
84. ime ZDT Mode An extended live time clock increases the collection time real time of the acquisition to correct for input pulse train losses incurred during acquisition due to system dead time This corrected time value known as the live time is then used to determine the net peak count rates necessary to determine nuclide activities As an example consider the case where the spectrometry amplifier and ADC are 60 dead during the acquisition the elapsed real time will be Live Time Real Time 1 0 60 _ Live Time x 100 100 Dead Time If the N counts in the gamma ray peak in the spectrum are divided by the elapsed live time the resulting counting rate N Live Time is now corrected for dead time losses The standard deviation in that counting rate is y N Live Time Unfortunately extending the counting time to make up for losses due to system busy results in an incorrect result if the gamma ray flux is changing as a function of time If an isotope with a very short half life is placed in front of the detector the spectrometer might start out with a very high dead time but the isotope will decay during the count and the dead time will be zero by the end of the count If the spectrometer extends the counting time to make up for the lost counts it 9 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 will no longer be counting the same source as when the losses occurred As a result the number
85. ing the length of the high voltage cable to the absolute minimum The DIM is only needed for non SMART 1 detector use The DSPEC Pro uses the following DIMs for support of non SMART 1 detector systems e DIM POSGE For any non SMART 1 positive bias HPGe detector includes short leads with mating connectors for connecting to existing detector cabling 500 V to 5000 V e DIM NEGGE For any non SMART 1 negative bias HPGe detector includes short leads with mating connectors for connecting to existing detector cabling 500 V to 5000 V e DIM POSNAI For any positive bias Nal detector includes short leads with mating connectors for connecting to existing detector cabling 100 V to 1800 V e DIM 296 For any positive bias Nal detector with Model 296 ScintiPack tube base preamplifier bias supply for Nal detectors with 14 pin 10 stage photo multiplier tubes 0 V to 1200 kV 1 7 3 How State of Health SOH is Monitored The SMART 1 HPGe detector SOH function operates as follows When the acquisition is started the DSPEC Pro clears all the bits of the SOH byte in the SMART 1 HPGe Detector memory During data acquisition the SMART 1 HPGe Detector monitors the conditions listed above Should any of these values fall outside a specified range even if they subsequently return to normal the relevant SOH bit is set The bits stay set until cleared externally with the Acquire Clear command in MAESTRO or the firmware commands CLEAR CLEAR_A
86. is trapped it does not contribute to the signal The reduced signals have a different rise time than the full signals The relationship between rise time of the signal and charge trapping is the basis of the Charge Trapping Corrector 794380D 0914 1 INTRODUCTION Maximum protection time gt Minimum protection time Pulse Amplitude 0 5 10 15 20 25 30 35 40 45 Time Figure 1 Demonstration of the DSPEC Pro s Minimum and Maximum Protection Times in Enhanced Throughput Mode At the maximum protection time setting the DSPEC Pro processes pulses in the conventional way The digital filter in the DSPEC Pro measures the amount of charge collected for each event and uses the result to increment the spectrum memory location associated with that charge measure ment The Charge Trapping Corrector also measures the pulse rise time for the event The pulse rise time is used to adjust the very fine gain For each pulse the measured charge is increased by the appropriate fine gain factor to correct for the signal lost due to carrier trapping 1 4 The Low Frequency Rejector LFR Filter In designing a multichannel buffer MCB that can be used in conjunction with mechanical coolers ORTEC has developed a new digital filter the Low Frequency Rejector LFR filter capable of correcting the pulse output signal for changes in the baseline caused by cooler induced microphonics In many ways digital filters are easier to understand than
87. istic deficit Unfortunately this doesn t compensate for resolution loss due to charge trapping which results in variations in charge collection effi ciency over the crystal volume The DSPEC Pro introduces our new Resolution Enhancer which enables you to correct for charge trapping by training the spectrometer to accommodate the particular performance of your detector Enhanced Throughput Mode This signal processing method allows the spectrometer to begin sampling the next pulse before the preceding one has returned to baseline The effect is optimum throughput while maintaining resolution and peak shape List Mode In List Mode the DSPEC Pro records and stores the pulse value with a time stamp for every pulse generated by the detector With List Mode you can write your own programs that can reconstruct histograms for any time segment without dead time between histograms or make histograms for overlapping time slices Data can be stored easily for reconstruction of any time frame needed If your application requires real real time monitoring no other instrument comes close for HPGe applications DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 1 1 2 Proven Technologies of the DSPEC Family High Speed USB Interface Connect the DSPEC Pro via high speed USB to any computer running under Microsoft Windows 8 7 or XP SP3 A nearly unlimited number of DSPEC Pros as well as any combination of other ORTEC US
88. it 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 SR p E A tg get ed 49 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Bit 10 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 42 43 44 45 50 Meaning Software selectable analog offset HV power supply Enhanced HV SET_HV SET SHOW_HV_POL SHOW_HV_ACT Software selectable HV range ENA_NAI DIS_NAI Auto PZ START_PZ_AUTO 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 MicroONOMAD Software selectable DPM address SET_DPM_ADDR Multiple devices e g 919 Sof
89. l time stamps on each of the ADC words Using the CONNECTIONS time stamp and the hardware time word you can determine the 64 bit Windows time associated with each ADC word in the buffer 93 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Refer to the Win 32 function GetSystemTimeAsFileTime for more information about the 64 bit time format contained in these words In the case where the data acquisition program does not get all of the data from the spectrometer the data block will not contain a hardware time word In this case the data acquisition program must immediately request another block of data from the spectrometer in order to find the corre sponding hardware time stamp Note that the second block will begin with another CONNEC TIONS time stamp which will correspond to another hardware time word The data acquisition program must associate the first CONNECTIONS time stamp to the first hardware time word and the second CONNECTIONS time stamp to the second hardware time word even though the first hardware time word appears after the second CONNECTIONS time stamp For example if you request 16384 words and the first returned word is 65532 indicating that 16380 data words plus 4 overhead words were returned you should immediately request another block of data The DSPEC Pro has buffer storage for up to 96k 32 bit words Therefore six requests may be needed to drain the buffer and find all of the hardware time w
90. lattop System Gain Settings Coarse Gain Settings 1 to 32 in binary steps 1 2 4 8 16 32 Fine Gain 0 45 to 1 The available range of gain settings supports all types of HPGe detectors Specifically the fol lowing maximum energy values are achievable using the standard ORTEC preamplifier maxi mum to minimum gain e COAX 187 keV 12 MeV GLP SLP 16 5 keV 1 MeV Amplifier Input Polarity Selectable via software System Conversion Gain Software selectable as 16384 8192 4096 2048 1024 or 512 channels Preamplifier Software selectable as either resistive or TRP preamplifier 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 or anticoincidence For the legacy LO AX and IGLET X detector types the respective energy ranges are 94 keV 6 MeV and 8 keV 500 keV 45 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Digital Filter Shaping Time Constants e Rise time 0 8 us to 23 us in steps of 0 2 us e Flattop 0 3 to 2 4 in steps of 0 1 ps Dead Time Correction Extended live time correction according to Gedcke Hale method Accuracy area of reference peak changes lt 3 from 0 to 50 000 cps Low Frequency Rejector LFR When ON removes low frequency lt 3 kHz input noise
91. le Olean ee wie ae aA 97 Vii Safety Instructions and Symbols This manual contains up to three levels of safety instructions that must be observed in order to avoid personal injury and or damage to equipment or other property These are DANGER Indicates a hazard that could result in death or serious bodily harm if the safety instruction is not observed WARNING Indicates a hazard that could result in bodily harm if the safety instruction is not observed CAUTION Indicates a hazard that could result in property damage if the safety instruction is not observed In addition the following symbols may appear on the product AN DANGER Hazardous voltage AN ATTENTION Consult the manual in all cases where this symbol is marked in order to determine the nature of the potential hazards and any actions that must be taken to avoid them Protective earth ground terminal Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product Cleaning Instructions To clean the instrument exterior e Disconnect the instrument from the power source Remove loose dust on the outside of the instrument with a lint free cloth Remove remaining dirt with a lint free cloth dampened in a general purpose detergent and water solution Do not use abrasive cleaners Allow the instrument to dry completely before reconnecting it to the power source Vili Intentionally blank
92. licking Coarse RNE GLO Sg the Start Auto optimize button The changes you Count Rate too low for for OPTI make on most property tabs take place immediately Close There is no cancel or undo for these dialogs Figure 13 DSPEC Pro Amplifier Tab 24 794380D 0914 2 GETTING STARTED Gain Set the amplifier coarse gain by choosing 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 32 Input Polarity These buttons select the preamplifier input signal polarity for the signal from the detector Normally GEM p type detectors have a positive signal and GMX n type have a negative signal Baseline Restore This 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 from dc shifts or mains power ac pickup The baseline settings control the time constant of the circuit that returns the baseline to zero There are three fixed choices Auto Fast and Slow The fast set ting 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 DSPEC Pro even when the power is off Th
93. lifier 2 Properties for DSPR 0008 tab which accesses the advanced shaping controls including the InSight Virtual Oscilloscope mode High Voltage About Status Amplifier Presets Amplifier2 AmplfierPRO ADC MDA Preset Stabilizer The many choices of Rise Time let you precisely control the tradeoff Tit 0 00000 between resolution and throughput Pole Zero see Section 2 4 This setting affects InSight both the rise and fall times so oar Start St 2200 changing it spreads or narrows the quasi trapezoid symmetrically Close Use the up down arrows to set the Rise Time from 0 8 to 23 0 us Once the unit has been optimized Rise Time 12 00 Width 0 80 Flattop Figure 14 DSPEC Pro Amplifier 2 Tab according to Section 2 3 1 you can use any Rise Time without having to re optimize The value of the rise time parameter in the DSPEC Pro is roughly equivalent to twice the inte gration time set on a conventional analog spectroscopy amplifier Thus a DSPEC Pro value of 12 us corresponds to 6 us in a conventional amplifier Starting with the nominal value of 12 0 26 794380D 0914 2 GETTING STARTED 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 The Flattop controls adjust the top
94. ll be written back to the corresponding MCB 21 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual r Configure Instruments Version 8 01 1 Somme wr 13 14 Instr Number amp Description DSPec DSPec DS50 00P2U2 MCB 1 DS50 11195158 MCB 1 DS50 11195158 MCB 2 Station 6 Right Station 5 Left Station 3 Station 4 DSPEC PRO MCB 129 Input System Close Cancel Help Renumber All Renumber New Figure 10 MCB Numbering and Descriptions 2 2 4 1 Configuring a New Instrument The first time a new instrument is detected the dialog shown in Fig 11 will remind you that all new instruments must be assigned a unique non zero ID number Click OK You can either manually change the ID Number and Description as described in the next subsection or you can click the Renumber New button to renumber only the new instruments This is the first time you have configured these detectors 794380D 0914 All detectors must have an ID number Since none of your detectors have ID numbers it is recommended that you press Renumber All to establish initial ID numbers for your detectors Figure 11 New Instruments Must Have a Non Zero ID Number NOTE We strongly recommend not using the Renumber All button In addition we strongly recommend not renumbering MCBs that belong to other users as this could affect the interaction between their MCBs and their ORTEC soft
95. longer be applicable When using spectrum analysis applications such as GammaVision and Scinti Vision you can create an analysis options file SDF or SVD file for each system geometry that you use and include in it a set of MDA presets specific to that geometry efficiency calibration and nuclide library You can then recall this tailored analysis options file as needed 2 4 Setting the Rise Time in Digital MCBs To achieve the best results when using a digital spectrometer such as the DSPEC Pro we recommend that you set the rise time of the pulses being processed by the digital filter to the minimum value for the resolution needed The pulse rise time and also fall time is based on the time required for each pulse o I V2 to reach its peak value This peaking time F 8 is about twice that indicated by the conven g 6 tional time constants displayed on the front of 4 panel of commercial analog amplifiers For a 5 example germanium detectors are often specified at a 6 us time constant this set 1 5 9 15 20 30 50 75 95 105 120 130 140 ting is equivalent to 12 us peaking rise Count Rate kcps time in our digital spectrometers Figure 25 An Example of the Tradeoff Between Throughput and Count Rate Up to some value of rise time one can expect improved resolution with increasing rise time there will however be a tradeoff in maximum throughput to memory Figure 25 illustrates an example of this tradeoff
96. lue 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 C01000088 1000 points in the waveform SHOW_LFR Tells whether LFR mode is enabled Responses SIF LFR mode disabled IT LFR mode enabled SHOW_LIVE Reports the contents of the live time counter in units of 20 ms 50 ticks s See also CLEAR_COUNTER and SET_LIVE 78 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES 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 Responses G0000000000075 lt CR gt Live time preset report
97. m charac ters and lt CR gt represents the ASCII carriage return character Axxxcecc lt CR gt xxx is a single 8 bit unsigned number Cxxxxxccc lt CR gt XXXXxX s a single 16 bit unsigned number Dxxxxxyyyyyccc lt CR gt XXXxXx and yyyyy are 16 bit unsigned numbers Exxxxxccc lt CR gt XXXXX is a single 16 bit alarm mask Fssss lt CR gt Ssss is a variable length ASCII character sequence no checksum is sent with this record Gxxxxxxxxxxccc lt CR gt XXXXXXXXXX s a Single 32 bit unsigned number IT lt CR gt True response to a SHOW command no checksum IF lt CR gt False response to a SHOW command no checksum Jxxxxxyyyyy cec lt CR gt Response to SHOW_CONFIGURATION command MXXXXXXXXXx ccc lt CR gt Response to SHOW_STATUS command Nxxxyyyzzzccc lt CR gt XXX yyy and zzz are 8 bit unsigned numbers 4 2 2 MCB Commands This section lists each command with a description of its operation The descriptions include a list of any error codes that may result As described in the two preceding sections the usual response is a macro error code of 0 and a micro error code of 0 no errors 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 The commands are listed in alphabetical order each starting with a command prototype line Uppercase letters numeric digits blank sp
98. ment 5344 e acaee Fst dvaeace chase Pa raters 22 2 2 4 2 Customizing ID Numbers and Descriptions 22 2 2 5 Attaching More Than One DSPEC Pro to the Computer 23 2 2 6 Connecting to and Disconnecting from the Computer 24 2 3 DSPEC Pro MCB Properties in MAESTRO 9 o c4 see ceed bs va eee te eedaae we ewd 24 DA AMPTE tein Ran ne ak te aCe ene eRe O Meo A E kenge 24 2S Dy AMPIE 2 God ne te delat we suck ee heb els te nee wee NORE Rh Ee eis 26 29D als MSI SOE Mods wate c dk ersch aed om he we a aad E Bend Gee Ge Ce Be a 27 Mark I VOCS lt 5 ore an aceen econ puice te ec bad E E E EE 29 Z3 oe AMPIE PRO Re ee rae eae ONT ORS aD POC OR Fete Ee ae Er oe ee 30 2 3 3 1 Training the Resolution Enhancer 200005 32 To Enable and Train the Enhancer 2005 32 To Turn the Enhancer Off 007 8 tooo Bacar ne hater nee 33 ZO ADG peice tek ee Ne ey Laken 2a ede tik suchen Salted oe oom eed 33 Zid ois SLA DIMZER 437 er ee Rela wo pinay Oe cua ko SA a O alae ae as 34 29 07 HeH VONACE 5 cdi Gd dn E mated nace abn ed Rawat end eR ae eR 35 2 Sl SEO OUNL ee arse ed ea MAC we Mee nS Rea Beg dota Gt Rl N eh 36 PAE ie SAMUS eigecce E ww aly HED a eC ew AS GER ER ca 36 De PTESEIS tan ae crt oye ieee Ben ann had Gee E OA Ew ee Ee 39 23 10 MDA Preset ex cae vie diy vinta aie ones nie Rede eee e Met ye ee KEW Sea eee 40 2 4 Setting the Rise Time in Digital MCBs i
99. mplifier Amplifier2 AmplifierPRO ADC Stabilizer High Voltage About Status Presets MDAPreset The presets can only be set on an MCB that is not acquiring data _ Real Time s alii during acquisition the preset field ok Fie backgrounds are gray indicating pas a that they are inactive You can use ROI Peak ents on p any or all of the presets at one time i To disable a preset enter a value of Pa iNi SEES zero If you disable all of the presets Overflow data acquisition will continue until manually stopped Figure 23 DSPEC Pro Presets Tab 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 start the next acquisition or Close the Properties dialog 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 additi
100. mplifier2 AmplifierPRO ADC Stabilizer reads the position of the marker and sO E Zato Stab zajion Enabled inserts values into the fields If the Solace boleh Center Chan 0 marker is in an ROI the limits of the Width f1 Width f1 ROI are used If the marker is not in See eee Sasa esos an ROL the center channel is the Akame Achustineri marker channel and the width is 3x Initialize 0 Initialize 0 the FWHM at this energy Now L me click the Enabled checkbox to turn the stabilizer on Until changed in this dialog the stabilizer will stay enabled even if the power is turned off When the stabilizer is enabled the Center Channel and Width cannot be changed Figure 19 DSPEC Pro Stabilizer Tab 2 3 6 High Voltage Figure 20 shows the High Voltage for DSPR 0008 tab which allows you to turn the high voltage on or off set and monitor the voltage and choose the Shutdown mode Amplifier Amplifier2 AmplifierPRO ADC Stabilizer High Voltage About Status Presets MDAPreset Target O Volts Shutdown TTL X or Actual O Volts The shutdown can be TTL ORTEC or SMART The ORTEC mode is used for all ORTEC detectors except SMART 1 detectors Use the SMART option for those detectors Check with Off Overload the detector manufacturer for other detectors The TTL mode is used for most non ORTEC detectors Sodium lodide Detector Figure 20 DSPEC Pro High Voltage Ta
101. n the list can be selected by sending the SET_MODE_ZDT command with a mode number The mode number is implied by the loca tion of the mode in the list For example the first item in the list had a mode number of 0 To select the first item send SET MODE _ZDT 0 The second item has a mode number of 1 and so on Response MODE_ZDT NORM_CORR CORR_ERR Mode 0 stores the normal and corrected spectra Mode 1 stores the corrected and the error spectra LIST_ROI SAMPLE Lists the valid ROI sample settings Response ROI SAMP PUR BLN BLRG BLD BUSY GATE RESV PKDET LIST_SHAP_CUSP Not used by the DSPEC Pro included for backward compatibility LIST_SHAP_FLAT Lists the valid flattop width settings Response SHAP_FLAT 0 3 2 4 3 24 Settings are 0 3 to 2 4 in 22 steps of 0 1 us LIST_SHAPE_RISE Lists the valid rise time settings Response SHAP_RISE 0 8 23 0 4 115 Settings are 0 8 to 23 in 0 2 us steps LIST_SHUT Lists the valid shutdown settings Response SHUTDOWN TTL ORTEC SMART LIST_TIME_ETP Returns the range of valid protection time settings in the Enhanced Throughput Mode Response TIME_ETP 01 200 4 8000 Valid settings range from 0 1 us to 200 us in 25 ns increments 62 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES OFF Turns the DSPEC Pro off OPEN_FILE filename ext OPEN_FILE_FLASH RESET RESET_REMOTE No function in the DSPEC Pro included for backward compatibility SET_BLRE baseline T
102. nitored at all times You can select any six of these to be displayed simultaneously on the Status tab The parameters you choose can be changed at any time so you can view them as needed Two types of values are presented OK or ERR and numeric value The state of health SOH parameters read OK or ERR If the state is OK the parameter stayed within the set limits during the spectrum acquisition If the para meter varied from the nominal value by more than the allowed limit the 36 r Properties for DSPR 0008 Amplifier Amplifier2 AmplifierPRO ADC Stabilizer High Voltage About Status Presets MDAPreset DSPR 0008 Sample Acquisition Start Time Access 20 13 00 Friday November 08 2019 Read Write Firmware Revision Serial Number Acquisition Mode DSPR 046 RevB11 PHA Figure 21 DSPEC Pro About Tab Properties for DSPR 0008 Amplifier Amplifier2 AmplifierPRO ADC Stabilizer High Voltage About Status Presets MDA Preset Detector State Of Health DIM 24 State Of Heath OK DM stv State Ofrieath OK DIMAX State Of Health OK DIM 24V State Of Health OK Jor Temperature State Of Health OK Close Figure 22 DSPEC Pro Status Tab 794380D 0914 2 GETTING STARTED ERR is set until cleared by the program The numeric values are displayed in the units reported by the DSPEC Pro Security Detector temperature and Live
103. ntain settings in the event of a power interruption Presets Multiple presets can be set on any or all of the following Real Time Stops data collection when the real time reaches this value Live Time Stops data collection when the live time reaches this value ROI Integral Integral count stops data collection when the sum of counts in all ROI channels reaches this value ROI Peak Peak count stops data acquisition when the count in any ROI channel reaches this value maximum value of 2 1 counts 2x10 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 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 the computer does not have to poll the DSPEC Pro for the preset to operate See Section 2 3 10 for details on the MDA preset calculation Data Overflow Terminates acquisition when data in any channel exceeds 2 1 2x10 counts Digital Spectrum Stabilizer Stabilization Peak centroid zero and gain channel 2 to 16384 stabilization window width zero and gain 1 to 256 channels 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 3 1 1
104. o function in the DSPEC Pro included for backward compatibility DISABLE_HV Turns off the high voltage enable signal of the DSPEC Pro See the section on the bias supply for more information about the high voltage output See also ENABLE_HV and SHOW_HV DISABLE_HV_DIM Disables the use of the MCB connector on the back of the DSPEC Pro and causes the DSPEC Pro to suppress State of Health information see SHOW_HV_HEALTH command Also the command disables polling of a standard DIM module e g DIM POSNAT DIM POSGE DIM NEGGE or DIM 296 by the DSPEC Pro DISABLE_LFR Returns the DSPEC Pro to normal operation if the LFR filter is enabled See also ENABLE _ LFR and SHOW_LEFR DISABLE_NAI Switches the stabilizers to Ge mode See ENABLE_NAI DISABLE_OPTI_NEED Disables the reporting of an error when the DSPEC Pro 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 57 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 DSPEC Pro has not been pole zeroed DISABLE_REMOTE No function in the DSPEC Pro included for backward
105. o 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 88 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES Responses C00000087 lt CR gt Zero channel has not been set C00002089 lt CR gt Zero channel is channel 2 lowest possible channel C16382107 lt CR gt Zero channel is channel 16382 highest possible channel 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 lt CR gt Zero width is 3 channels lowest possible width C00256100 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 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 DSPEC Pro START_FLAT_AUTO Performs optimization of PZ and flattop correction for a single
106. ompanying CONNECTIONS Driver Update Kit P N 797230 selecting the USB based instruments family on the install wizard s Instrument Setup page 2 Install the accompanying MAESTRO MCA Emulation Software A65 BW 3 Connect the DSPEC Pro to the USB port on the computer 4 Run the MCB Configuration program to build a list of available ORTEC MCBs 19 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 2 2 1 Step 1 Install the CONNECTIONS Driver Update The first step is to install the CONNECTIONS Driver Update Kit P N 797230 according to its instruction sheet This software must be installed before MAESTRO can be installed The update kit s instructions tell how to install CONNECTIONS enable disable the drivers for your ORTEC MCB s and share ORTEC instruments across a network On the Instrument Families page be sure to mark the USB based instruments checkbox as shown in Fig 9 Otherwise the DSPEC Pro will not be able to communicate with the computer and MAESTRO software At the end of installation you will be directed to restart the computer Instrument Setup E Instrument Families Please check all items in this list that are connected to or CO DPM USB installed in this computer O Dual Port Memory plug in cards ISA slot Click Done when you are CO TRUMP PCI cards finished O DART or any other printer port based device O microBASE Item Description a 0 Miniature MCA miniMCA 1
107. on 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 Enter the Real Time and Live Time presets in units of seconds and fractions of a second These values are stored internally with 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 39 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Enter the ROI Integral preset value in counts With this preset condition the MCB stops count ing when the sum of all counts in all channels for this MCB marked with an ROI reaches this value This has no function if 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 p
108. oportional to the slope of the baseline during the energy measurement If the slope is known then so is the error introduced by the microphonics An excellent estimate of the slope can be obtained by using the trapezoidal filter itself to measure the slope both before and after the energy measurement Since the digital filter is always sampling the input signal it is only necessary to store 1 the values measured before the event is detected 2 the gamma ray energy measurement and 3 the values measured after the event is detected The modified trapezoidal digital filter for LFR from an InSight Virtual Oscilloscope trace is shown in Fig 4 A suitably weighted and averaged value of the before and after slope measurement is then subtracted from the energy measurement producing a measure ment essentially free of microphonic noise Although the inherent increase in the pulse proces sing time increases the dead time of the system the resolution can be greatly enhanced when periodic noise is present InSight BED WELL MCB 163 x H File Acquire Calculate Services ROI Display ov tl eD K C efa A 1 BEOWELL Mce 163 Trigger Random V Single Reset Delay 0 00 Baseline Restorer Auto E ps Fat Slow up feo 3 Pole Zero Auto 3237 Other Controls Q0RTEC 1247 32 PM Tue 4 1 2003 ba Marke 1 435 143 50 p5 1 039 Cnts Figure 4 LFR Enabled Digital Filter DSPEC Pro
109. ords In practice a program buffer of 96k words would always hold enough data to drain an instrument buffer assuming that all six requests were made in less than 1 second The following tables describe the format for the list mode data as returned by CONNECTIONS from the DSPEC Pro spectrometer Table 3 Geese List Mode Data Format 31 30 29 ADC Word 14 bit ADC value 16 bit real time in 200nS ticks RT Word x al 30 bit real time in 10 ms ticks LT Word ad Aitlive time in 10s teks Table 4 Spectrometer List Mode Data Format 24 23 15 ADC CRM 94 794380D 0914 APPENDIX B LIST MODE IN THE DSPEC PRO The ADC Word contains a raw 14 bit ADC value and a 16 bit real time stamp The Hardware Time Word contains the same 16 bit real time stamp In both cases this value represents the time that the word was created as represented by an internal clock that increments every 200 ns The 200 ns clock rolls over from 49999 to 0 which gives it a period of 10 ms Every time the 200 ns clock rolls over a RT Word and LT Word are created The 30 bit real time stamp on the RT word corresponds to the number of times the 200 ns clock rolls over The 10 ms real time clock and the 10 ms live time clocks are cleared when the CLEAR command is sent to the spectrometer Otherwise they increment every 10 ms while data is collecting Using the RT Word as a time standard and the 200 ns time stamps from the ADC word you can determine the time that any ADC ev
110. orrected mode compensates for dead time losses by extending the real counting time Hence a sample containing both a short lived high activity isotope and a long lifetime lower activity isotope will experience very high dead time losses during the first few seconds of the measurement as the short lifetime isotope decays rapidly This high dead time will cause the counting time to be extended after the short lived isotope has decayed to zero activity and the system will count the low activity isotope for 12 794380D 0914 1 INTRODUCTION the extra time Consequently the average activity of the short lived isotope will be under estimated If you anticipate significantly varying counting rates during the time taken to acquire the spec trum the CORR_ ERR ZDT mode should be used The CORR_ERR mode corrects for dead time losses over minuscule time intervals by adding counts to the ZDT spectrum in proportion to the instantaneous ratio of real time to live time Thus the dead time correction can correctly track rapidly changing counting rates The CORR_ERR mode should be used whenever the counting rate might change significantly during the measurement time In addition to the rapidly decaying isotope example above the CORR_ERR mode should be used when monitor ing cooling water flow from a nuclear reactor The CORR_ERR mode accommodates brief bursts of high activity in the water flowing past the gamma ray detector Both the corrected and error sp
111. 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 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 lt CR gt Conversion gain set to 512 channels SET_GAIN_CONVERSION 1024 lt CR gt Conversion gain set to 1024 channels 64 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES SET_GAIN_CONVERSION 2048 lt CR gt Conversion gain set to 2048 channels SET_GAIN_CONVERSION 4096 lt CR gt Conversion gain set to 4096 channels SET_GAIN_CONVERSION 8192 lt CR gt Conversion gain set to 8192 channels SET_GAIN_CONVERSION 16384 lt CR gt Conversion gain set to 16384 channels SET_GAIN_FINE value Sets the fine gain to value Value is a floating point value from 0 333 to 1 0 See also SHOW_GAIN_ FINE SET_GAIN_NEGATIVE Sets the amplifier input polarity to negative SET_GAIN_POSITIVE Sets the amplifier input polarity to positive SET_GAIN_PRESET co
112. plays the instrument ID name preset count conditions current live and real time dead time percentage if active input count rate HV status and value and the serial number of SMART 1 detectors Use a USB hub to quickly connect multiple instruments to your computer ORTEC CONNEC TIONS software supports any combination of USB devices to a total of 127 connected to a particular computer In addition any number of other ORTEC multichannel buffers USB and other interfaces can be connected to the same system Standard DSPEC Family Features The DSPEC Pro also offers the InSight Virtual Oscillo scope which allows you to optimize detector performance for a given application from the com puter our easy automatic pole zero adjustment and automatic baseline restorer and the highly accurate Gedcke Hale extended live time correction method 1 2 Enhanced Throughput Mode To optimally process an input pulse stream and thereby obtain the best spectral resolution the signal processing device should allow the input signal to return to baseline before beginning to process the subsequent pulse However in cases where some loss of resolution is acceptable it is possible for a DSP to begin processing a subsequent pulse before the first pulse has returned to the baseline provided the first pulse has returned to baseline when the peak detect of the second pulse occurs The ORTEC Enhanced Throughput Mode takes advantage of this feature of
113. pport Detectors equipped with the SMART 1 technology have their recom mended bias values preset at the factory No more shuffling through paperwork or looking for tags on the detector to find the right bias setting Simply turn on the electronics and the SMART 1 detector senses the detector temperature and applies the right high voltage bias Our SMART 1 detectors also allow our more recent MCBs such as the DSPEC 50 and digi DART to monitor and display detector state of health SOH during acquisition including detector temperature preamplifier power bias overrange and bias on off state This continuous SOH monitoring ensures the integrity of the acquired data A quick check of the SOH flag in the SMART 1 detectors shows if any parameter deviated from specification during the measure ment This is vitally important for environmental samples that must be counted for long periods of time and regulatory driven samples where chain of custody integrity means everything Patent pending Patent number 6 327 549 2 794380D 0914 1 INTRODUCTION Sample Changer Connections and Controls The DSPEC Pro connects easily to many types of automatic sample changer Compact Convenient Connectivity A small footprint means that the DSPEC Pro can sit right on the desktop Lightweight but rugged multiple units can be stacked on top of one another via their interlocking cases without fear of sliding or tipping The easy to read backlit LCD screen dis
114. r Sets the start date to the specified values Normally the start date and time are set automati cally whenever a device is started with the START command See also SHOW_DATE_ START SET_TIME_START and SHOW_TIME_START 63 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SET_DELAY_COLLECTION value Controls the pileup rejector by setting a width threshold such that if a fast channel discrimi nator 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 1 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 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 channel as determined by the conversion gain the gain
115. re Information o2 ta eat bee ad eee eet cdi eh eees 14 1 7 DSPEC Pro SMART 1 HPGe Detector Support 0 ee eee 14 1 7 1 SMART 1 HPGe Detector Construction 0 0 0 0 15 1 72 Use Older Detectors ratere tk ha Rass e E E ese Rae a a et 15 1 7 3 How State of Health SOH is Monitored 0 0 0 0000005 15 1 8 Host Computer and Software Requirements 0 0 00 cece eee eee 16 Lo About his Manual suras oe Paw ad woah y LR eet EAE E Sen wea ie aka 16 2 GETING STARTED costae ii Lg Gree a eee BOW a Mader Ss Ge Fe 17 Delis The D SPEC PrO oh aida oe aed tiene Hee WEES ROI AE BE be Ree Rao wie 17 2E Front Panely cererea ea ao ah oe Dried tha Tac sre a pe raha ah Ba aera cee hdtv 17 oe es Wael B Bs 0 ee a a re a ee ee 17 2 EZ CONOS cae c eee dealers Hines eke ke eee oy eee Bead 18 Debs SIRE AL Panel cicuaxeee plagues EE eid io ceawe due si gtamiave dat E EEN dawg nate done 18 2 2 Software and Hardware Installation 2 s 4s 6034 6244400108684 evs bes ees 19 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 3 4 2 2 1 Step 1 Install the CONNECTIONS Driver Update 0 20 222 Step 2 Install MAESTRO terisi epe vba eee ae eee VARGA A eee eee a 20 2 2 3 Step 3 Connect the DSPEC Pro to the Computer 21 2 2 4 Step 4 Run MCB Configuration to Communicate With Your MCBs 21 2 2 4 1 Configuring a New Instru
116. 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 0 positive 1 negative Bit 1 Bias supply overload 0 overload 1 normal Bit 2 HV enabled 0 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_ID Reports the sample ID string as was previously set by the SET_ID command Example Responses FSite 123 lt CR gt ID set to Site 123 FSample 123456789 lt CR gt ID set to Sample 123456789 SHOW_INPUT 0 Reports the state of the Sample Ready input Responses C00000087 lt CR gt Sample Ready input is low C00001088 lt CR gt Sample Ready input is high 77 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 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 window that have their ROI flag set 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 va
117. rise time instead of all rise times START_OPTIMIZE Starts optimization of PZ and flattop correction for all rise times 89 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 START_PZADJUST_AUTO Starts the automatic PZ process The automatic PZ is not complete until indicated by the auto 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 STEP_OUTPUT Causes a pulse to be output on the Change Sample output port The level of the Change Sample output is changed then returned to the level present when the STEP_OUTPUT com mand was received The duration of the intermediate level varies but is never less than 2 us Use the SET_OUTPUT_HIGH or SET_OUTPUT_LOW commands to establish an initial output level Responses C00000087 lt CR gt Initial and final level on Change Sample was low C00001088 lt CR gt Initial and final level on Change Sample was high STOP seg mask Stops the acquisition of spectral data The optional segment mask is provided for compati bility with other MCBs and may be any value from 0 to 65535 but is ignored STOP_OPTIMIZE Stops the optimization in progress The DSPEC Pro may be in an indeterminate mode See also START_OPTIMIZE STOP_PZ_AUTOMATIC Stops the optimization in progress The DSPEC Pro may be in an indeterminate mode See also START_PZ_ AUTOMATIC TERM No function in t
118. ryone using ORTEC instruments on your network should make this change To prevent others from renumbering your MCBs or performing any other actions except read only viewing password lock your MCBs with the MAESTRO Lock Unlock Detector command If you lock a detector that will be controlled by a JOB stream remember to include the proper password unlock commands in your JOB file see the MAESTRO user manual If a modified description has already been applied to a particular instrument you can restore the default description by deleting the entry in the Description field and re running MCB Config uration After MCB Configuration runs the default description will be displayed 2 2 5 Attaching More Than One DSPEC Pro to the Computer Once the drivers have been installed for one DSPEC Pro adding subsequent units is simple REMINDER Be sure to run MCB Configuration any time you add new DSPEC Pros or other ORTEC MCBs to your system or when you move an instrument from one USB port to another 23 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 2 2 6 Connecting to and Disconnecting from the Computer The USB connection allows you to connect DSPEC Pros to and disconnect them from a USB port without shutting down the computer or USB hub Note that if MAESTRO is running when you disconnect the DSPEC Pro you will see a detector not responding message on the status line at the bottom of the MAESTRO window
119. s it would for the Off ZDT mode 1 6 3 CORR_ERR ZDT and Error Spectra Stored In the CORR_ERR mode the estimation of the statistical uncertainty is stored in place of the LTC spectrum and is referred to as the error spectrum ERR In this mode the ZDT spectrum is used to measure the counts in a peak and the error spectrum is used to determine the uncer tainty of the measurement made in the corrected spectrum For example if the area of a peak is measured in the corrected spectrum by summing channels 1000 to 1100 the variance of the measurement can be determined by summing the counts in channels 1000 to 1100 in the error spectrum Or shown another way the counts in channel 7 can be expressed as N i y V i with a 1 sigma confidence limit where N is the corrected spectral data and V is the variance error spectral data The live time is set to the real time within the analysis engine during the analysis of ZDT spectra A CORR_ERR spectrum is analyzed as a regular spectrum most of the time with a few exceptions as listed below To calculate the peak area uncertainty the error spectrum is used If the peak limits are from L and H channels then the background variance is calculated as Using our gamma ray spectrum analysis software such as GammaVision or ISOTOPIC 11 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 E B n n B n n x H L 1 var 4 B sum of backgroun
120. s normally set automatically by the DSPEC Pro 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 DSPEC Pro 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 stored for a device when an acquisition is started See also SHOW_TIME SET_DATE SHOW_DATE SET_TIME_START and SHOW_TIME_START SET_TIME_ETP value Sets the Enhanced Throughput Mode protection time in microseconds value ranges from 0 1 us to 200 us in 25 ns increments Example SET_TIME_ETP 50 Set the protection time to 50 us 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_TRIGGER_POLARITY polarity This sets the polarity of the input trigger for the sample changer which occurs on the SAMPLERDYIN BNC to zero or 1 Zero means it is negative edge triggered and triggers on a high to low transition 1 means the trigger is positive edged and triggers on a low to high transition See also TRIGGER ENABLE_TRI
121. t CR gt Next ROI group starts at channel 1000 and is 50 channels long D0215000150086 lt CR gt Next ROI group starts at channel 2150 and is 150 channels long D0000000000072 lt CR gt No other ROI groups to report SHOW_OUTPUT 0 Reports the status of the Change Sample output port The output port status is reported as a 16 bit number that is 0 or 1 depending on the level last set by a SET_OUTPUT_HIGH or SET_OUTPUT_LOW command Responses C00000087 lt CR gt Change Sample output currently low C00001088 lt CR gt Change Sample output currently high SHOW_OVERFLOW_PRESET Reports the state of the overflow preset Responses IT lt CR gt Overflow preset enabled IF lt CR gt 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 is the maximum number of counts that can be stored in a 31 bit channel Responses G0000000000075 lt CR gt 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 81 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SHOW_PEAK_CHANNEL This command returns the number of
122. t Lowest Throughput minimum Protection Time maximum Protection Time Off Rise Time flattop 2 x Rise Time Flattop 3 x Rise Time 2 x Flattop 6 x Rise Time 3 x Flattop 31 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 Turning on this feature automatically sets the minimum protection time highest throughput rate based on your current Rise Time and Flattop settings however you can adjust this value at any time Each time you change the rise time or flattop the DSPEC Pro will automatically set itself to the new minimum protection time 2 3 3 1 Training the Resolution Enhancer The Resolution Enhancer can help reduce the low side peak tailing that results from increased charge trapping see the discussion in Section 1 3 It operates by measuring the rise time collec tion time of the pulses and adjusting the gain based on the rise time This is done on each pulse The gain adjustment value for the rise time is stored in a table The values in the table must be set by training the Resolution Enhancer Training requires two to four 15 minute data acqui sitions with a mixed gamma source for instance mixed gamma with Am The source should have sufficient activity that the detector registers a count rate of 5000 cps on the endcap Marking the Resolution Enhancer checkbox enables disables the learning mode Once trained the enhancer continues to operate until disabled as disc
123. tered in powers of 2 e g 8192 4096 2048 The up down arrow buttons step through the valid settings for the DSPEC Pro 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 The Upper Level Discriminator sets the level of the highest amplitude pulse that will be stored This level establishes an upper level cutoff by chan nel number for storage 2 3 5 Stabilizer The Stabilizer tab Fig 19 lets you adjust and monitor the gain and zero stabilizers which are discussed in detail in the MAESTRO user manual 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 1 The NORM_CORR LTC and ZDT mode is typically not used see Section 1 6 2 34 794380D 0914 2 GETTING STARTED To enable the stabilizer enter the for DSPR 0008 Center Channel and Width values manually or click the Suggest Region button Suggest Region High Voltage About Status Presets MDAPreset Amplifier A
124. the form of a pulse height value along with a time stamp that indicates the time the pulse arrived The data can be analyzed by the computer in real time to determine if some significant event has occurred or can be streamed to disk for analysis at a later time B 1 1 Spectrometer Data Format List Mode data is retrieved from the DSPEC Pro spectrometer by calls to the CONNECTIONS MIOGetData DLL function or the CONNECTIONS control GetRawData method A minimum of 4 and a maximum of 16384 32 bit words of data can be requested at a time Each request for data returns a block of 32 bit list mode words that begin with a 32 bit integer number of valid bytes followed by a 3 word CONNECTIONS time stamp thus the minimum of 4 words in a request The first word is the number of bytes returned not including the first 4 bytes The minimum value returned here is 12 indicating 3 CONNECTIONS time stamp words only and the maximum is 65532 indicating 3 CONNECTIONS time stamp words plus 16383 data words The CONNECTIONS time stamp represents the 64 bit Windows file time that corresponds to the exact time that the request for data is sent to the spectrometer At the exact time the CONNEC TIONS requests data from the spectrometer the spectrometer creates a hardware time word in the list mode data stream that indicates the corresponding time within the spectrometer The 16 bit real time number on the hardware time word is from the same time source as the 16 bit rea
125. their analog counterparts Figure 2 shows the voltage step output produced at the preamplifier by the collec tion of charge produced by absorption of a gamma ray and the resulting trapezoidal weighting function in a digital spectrometer The difficulty in the measurement is to precisely determine the height of the step pulse because the baseline contains noise A fairly obvious estimate of the 5 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 step signal is obtained by averaging the M N digitized samples of the signal before and after the step M samples immediately after the event are first ignored to allow for a maximum rise time of M times the sample interval N samples of the baseline prior to anal anetyli _ rane K the step pulse are averaged and then sub N N N tracted from the average of N samples Figure 2 Typical Trapezoidal Weighting Function taken after the step pulse This simple right Arising from Detector Preamplifier Output procedure produces a trapezoidal weight Signal left ing function with a rise time of N sample intervals and a flattop of M sample intervals The maximum value of the trapezoid output occur ring at the end of the flattop is the best estimate of the step height and therefore the gamma ray energy With a proper selection of M and N this filter is very nearly the optimum filter for a system with noise arising only from the detector leakage
126. ts 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 AMT 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 AMT 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 AMT 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 the same procedure and
127. tware 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 Software programmable SCA upper and lower thresholds Software selectable MCS mode input sources Uncertainty statistical preset SET_UNCERT_PRES Features vary by input SHOW_FEATURES depends on device segment multi input MCBs only 794380D 0914 3 SPECIFICATIONS Bit 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 2B 74 75 76 37 78 79 80 81 Meaning 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 VERI LIST_GAIN_FINE Software enabled pil
128. unt No function in the DSPEC Pro included for backward compatibility 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 chan nels 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 SET_GATE_ANTICOINCIDENT Causes the DSPEC Pro 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 DSPEC Pro to use the ADC gate input signal in coincident mode See also SET_GATE_OFF SET_GATE_ANTICOINCIDENT and SHOW_GATE SET_GATE_OFF Causes the DSPEC Pro to ignore the state of the ADC gate input signal See also SET_GATE_COINCIDENT SET_GATE_ANTICOINCIDENT and SHOW_GATE 65 DSPEC Pro Digital Gamma Ray Spectrometer User s Manual 794380D 0914 SET_HV value This sets the HV bias to value in volts SET_ID id string Sets the sample id string This string can be up to 1
129. ussed on page 33 NOTE This feature typically improves the shape of low energy peaks moreso than high energy peaks and does not improve poor resolution due to causes other than charge trapping To Enable and Train the Enhancer Note that this procedure requires detector recalibration 1 Right click in the spectrum window and turn on the Input Count Rate option 2 Set the desired bias and gain position the source to deliver a count rate of 1000 5000 cps and start the Optimize routine A message at the bottom of the Amplifier tab will indicate whether the count rate is too high or low At the optimum count rate optimization should take less than 5 minutes 2 Issue the Clear command position the source on or near the endcap set a Real Time preset of 1000 seconds and acquire a spectrum 3 Energy calibrate on the lowest and highest peaks for instance the Am 59 54 keV and Co 1332 51 keV gamma rays use the Peak Info command to obtain the FWHM data for the 41 Am Cd Cs and Co peaks mark the Cs 661 62 keV peak as an ROI and save the spectrum with a name and optional sample description indicating the MCB has been auto optimized 32 794380D 0914 2 GETTING STARTED 4 Position the marker in the Cs peak then switch to the Stabilizer tab In the Gain Stabilizer section click Suggest to capture the peak channel and width of the Cs ROI click the cor responding Initialize button then return to the Amplifier P
130. ut Mode To enable a particular feature mark the cor 30 794380D 0914 2 GETTING STARTED responding checkbox Any or all of these features can be used at one time however the LFR and Enhanced Throughput modes must be set up before the Resolution Enhancer is configured as discussed below Note that once an MCB is trained for the Resolution Enhancer see the following section it must be retrained if any settings are changed that can affect peak shape or position e g bias gain rise time flattop PZ r Properties for DSPR 0008 High Voltage About Status Presets MDAPreset Amplifier Amplfier2 AmplfierPRO ADC Stabilizer Kicesssseseseesesassescastseessess Seecszecseumiisesessstass Resolution Enhancer Enables resolution enhancement for the Gain Stablilzer Enhanced Throughput Mode Protection Time 12 800 us Figure 17 DSPEC Pro Amplifier PRO Tab Low Frequency Rejector This feature is discussed in detail in Section 1 4 The DSPEC Pro cannot optimize or pole zero in LFR mode Optimize or PZ with the filter off then turn it back on for data collection e LFR mode affects the available range of protection times in Enhanced Throughput Mode as discussed in the next paragraph Enhanced Throughput Mode See Section 1 2 for a discussion of this feature The valid Protection Time settings in 25 ns increments range as follows LFR Mode Highest Throughpu
131. utput 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 0 positive 1 negative Bit 1 Bias supply overload 0 overload 1 normal Bit 2 High voltage enabled 0 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_ACTUAL Returns the value of HV actually on the detector 76 794380D 0914 4 FIRMWARE COMMANDS AND RESPONSES SHOW_HV_DIM Indicates whether HV_DIM is enabled or disabled SHOW_HV_HEALTH Returns the status of the state of health for the detector as reported by the DIM or SMART 1 SHOW_HV_POLARITY This returns the HV polarity defined in the DIM as a F record Responses FNEG lt CR gt The HV is set to negative FPOS lt CR gt The HV is set to positive SHOW_HV_RECOMMEND Returns HV in volts 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 Dvvvvvsssssccc lt CR gt where vvvwv represents the HV setting and sssss
132. ware for instance if they control their MCBs with JOB files e g the JOB file command SET_DETECTOR 5 or use the GammaVision or ISOTOPIC spectroscopy applications See also the NOTE FOR MULTIPLE USERS ON A NETWORK in the next section 2 2 4 2 Customizing ID Numbers and Descriptions If you wish you can change the instrument ID Numbers and Descriptions by double clicking an instrument entry in the Configure Instruments dialog This will open the Change Description or ID dialog Fig 12 It shows the physical MCB location read only and allows you to change the ID Number and Description If this is a first time installation of ORTEC products all your instruments will be new 22 794380D 0914 2 GETTING STARTED f Change Description or ID Instrument Input System ID 132 1 USER PC 19 fare Cancel Description Figure 12 Change MCB Number or Description Make the desired changes and click Close Any changes you have made to an ID number or description will then be written back to the corresponding MCB NOTE FOR MULTIPLE USERS ON A NETWORK There are two ways to reduce the chance that other users will renumber your MCBs e Add the I flag to their MCB Configuration command line as described in the CONNEC TIONS Driver Update Kit instructions This will allow you to assign whatever ID Numbers you wish regardless of the numbers assigned by other users on your network Ideally eve
133. y will ask you to confirm shutdown press the backlight button to power down or ON OFF to ignore the shutdown command Backlight button Press to turn the display backlight on and off We recommend use of the backlight for easy viewing 2 1 2 Rear Panel Figure 8 shows the rear panel e 12 15 VDC Connects to the accompanying ac dc power adapter e DETECTOR Attach to the SMART 1 HPGe detector or DIM cable 18 794380D 0914 2 GETTING STARTED WARNING ORTEC DSPEC Pro NO USER SERVICEABLE PARTS OPENING CASE VOIDS WARRANTY IADE IN USA U S A PATENTS RS 232 5 821 533 12 15V DC 5 872 363 5 912 825 ae lol 6 327 549 MAX PWR 18W SAMPLE USB CHANGE OUT READY IN DETECTOR cE A CO Figure 8 DSPEC Pro Rear Panel e USB Connects to the host computer Note that you can connect to and disconnect from the computer without restarting Windows or MAESTRO However if you disconnect with MAESTRO running an error message will be generated When you reconnect to the computer you must reselect this MCA from MAESTRO s detector droplist as described in the MAESTRO user manual 2 2 Software and Hardware Installation Installing the DSPEC Pro and the MAESTRO MCA Emulation Software takes just four easy steps You must have Administrator access in Windows to install MAESTRO For easiest installation do not connect the DSPEC Pro to your computer until MAESTRO has been installed 1 Install the acc

Download Pdf Manuals

Related Search

Related Contents

Fuji FinePix 4900 Zoom Digital Camera  Wind River Workbench (Linux Version) User`s  Moleview User Guide  Télécharger - scierie  TPS2410EVM and TPS2411EVM User's Guide    2.3 Teacher Management system  Trust Summer  

Copyright © All rights reserved. Failed to retrieve file