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1. Strip Chart Recorder or ORTEC 487 Spectrum Scanner Recorder X Y Plotter Fig 4 1 Open Loop System be a sffooth plot of the energy spectrum analyzed If a digital rate meter ORTEC 434 is used then the recorder plot will be a histogram of the energy spectrum analyzed 4 2 CALIBRATION ADJUSTMENTS START LEVEL A trim potentiometer R88 is accessible through the top of the module for calibrating the full range starting voltage 10 00 V dc This trim potentiometer is that one nearest the rear of the module The output voltage may be monitored with a digital voltmeter at the 487 front panel test point while this adjustment is being made For this adjustment RESET should be depressed and then the START LEVEL control should be turned full clock wise SWEEP TIME Another trim potentiometer R130 is accessible through the top of the module for adjusting the frequency of the internal oscillator SWEEP TIME This potentiometer is the one nearest the front of the module This adjustment is made easily by observing the output waveform on an oscilloscope and adjusting the time spacing between adjacent channels The input coupling into the oscillo scope must be ac For example with the SWEEP TIME control set at 1 min the time spacing between channels dwell time at each channel would be 60 sec 1024 or 58 6 us SPAN The span can be adjusted more accurately than by merely relyi2. 55 START FR Ad EP Ti 24 CNB 26 75 reser R P DIO Rios T 24 end Pos OUTPUT L RA O ICO mV RP RECORDER OUT 2 y UNLESS OTHERWISE NOTED P 1 ALL NEWS ARE 2 8 45 2 ALL PNPS ARE 2N3 38A 3 ALL DIODES ARE INdOOS 4 ALL RESISTORS MARKED HT ARE ME 1 gn 5 ALL RESISTORS ARE IN OHMS 6 ALL CAPACITORS ARE IN sf 165 Ib IS IOST 18 19 ARE yi 214 UNLESS OTHENPASE SPECIFIED 7 E or Tec EEES mi TOLERANCES am fsa aww y 100 MIDLAND ROAD DAK RIDGE TENNESSEE 37830 MODEL 497 SPECTRUM SCANNER EN gt D BATES ee 87 0057 ey EG G ORTEC 76 Offices in 49 Countries For more information on EG amp G ORTEC products or their applications contact yourlocal EG amp G ORTEC Representative or United States EG amp G Incorporated 100 Midland Rd Oak Ridge 37830 telephone 615 482 4411 Telex 55 7450 W Germany EG amp G ORTEC GmbH Munich telephone 089 98 71 73 United Kingdom EG amp G ORTEC Limited Bracknell telephone 55455 France EG amp G ORTEC S A R L Rungis Cedex telephone 687 25 71 Italy EG amp G ORTEC SpA Milan telephone 738 6294 Brazil EG amp G ORTEC Limitada Sao Paulo S P telephone 275 3943
3. FR STR LE w r 1 tt 107 i EO WIV ie 10 gt CHANNELS ga 128 VU A RAMP vo MINUTES SINGLE CYCLE FULL SWEEP AUTO RECYCLE STEP ADVANCE START STOP RESET gt gt 12V 150mA 11 13 14V 110mA A F L OUTPUTS RECORDER OUT RESET 9 73 a ORTEC 487 SPECTRUM SCANNER 1 DESCRIPTION The ORTEC 487 Spectrum Scanner is a program control led baseline sweep generator designed as an accessory to an ORTEC single channel pulse height analyzer It furnishes the external baseline for the analyzer and controls a program by which the analyzer window can be swept through an energy spectrum The 487 can be included as an integral part of a data acquisition system to obtain count rate versus energy level information The lower level threshoid or baseline of the analyzer is stepped through an adjusted span within the total dynamic range of an amplifier analog output tor x ray and nuclear applications The starting level span number of steps and dwell time at each step are ali separately adjustable on the front panel Both positive and negative bias polarities are available simultaneously to permit universal application to other instruments The automatic program identifies a cycle as one complete series of steps of the output baseline level starting at an adjusted level of between 1 and 10 V and stepping toward zer
4. flip flop which eliminates switch bounce from the START push button switch IC16A and IC16B form an R S flip flop for the start reset function Suppose that in the FULL SWEEP mode a Start input Is obtained either from the front panel START push button or the rear panel ADVANCE input A negative transition at pin 7 of IC19A will occur which will be inverted by IC19B This positive signal at pin 6 of IC19B will set the Start reset flip flop IC16A and IC16B The resulting negative transition at pin 6 of IC16B will allow the oscillator pulser to pass through the gate IC158B which was closed up to now Thus a train of pulses will appear at point F which is the input of the least significant bit of the binary counter The purpose of grounding points G H J and K successively with the CHANNELS switch is to Inhibit the contribution of the corresponding least significant bits to the output staircase waveform In the STEP ADVANCE mode suppose that the START push button is depressed This action will set pin 7 of the Start stop flip flop consisting of IC14A and IC14B low Simultaneously pin 6 of IC16B will be set low Thus input pulses present at the ADVANCE input will pass through the gate IC15A and appear on one of the points A B C D or E according to the setting of the CHANNELS switch Suppose for example that the CHANNELS control is set at 64 Then the clock pulses will be present at point C and thus be fed into the fifth binar
5. of a strip chart recorder whose input circuitry consists cf a load to some negative supply voltage then the GATE output would supply up to 50 mA of current to enable the chart to advance while the 487 is sweeping 6 MAINTENANCE INSTRUCTIONS The only maintenance that the 487 should require is routine calibration of the 401A Power Supply voltages All power supply voltages 12 and 24 should be kept within 0 05 V of their proper value For calibration adjustments internal to the 487 refer to Section 4 2 of this manual Calibration Adjustments The 487 may at any time be returned to ORTEC for repair service at nominal cost Our standard procedure requires that each repaired instrument receive the same extensive quality control tests that a new instrument receives Before returning the instrument contact Customer Service at ORTEC 615 482 4411 for informa tion concerning shipment of the instrument BIN MODULE CONNECTOR PIN ASSIGNMENTS FOR AEC STANDARD NUCLEAR INSTRUMENT MODULES Pin Function 3 volts 2 3 vol 3 Spare Bus 4 Reserved Bus 5 Coaxial 6 Coaxial 7 Coaxial 8 200 volts dc 9 Spare 10 6 volts 1 6 volts _ 12 Reserved Bus 19 Spare 14 Spare 15 Reserved 12 volts 12 volts 18 Spare Bus 19 Reserved Bus 20 Spare 21 Spare 22 Reserved PER TID 20893 Function Reserved Reserved Reserved Spare Spare 24 volts 24 volts Spare Bus Spare Spare 115 volts ac Hot Powe
6. CNEGEG ORTEC Model 487 Spectrum Scanner Operating and Service Manual CI DA Model 487 Spectrum Scanner Operating and Service Manual This manual applies to instruments Rev 05 on rear panel Printed in U S A 0696 0 50C 0279 STANDARD WARRANTY FOR EG amp G ORTEC INSTRUMENTS EG amp G warrants that the items will be delivered free from defects in material or workmanship EG amp G ORTEC makes no other warranties express or implied and specifically WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE EG amp G ORTEC s exclusive liability is limited to repairing or replacing at EG amp G ORTEC s option items found by EG amp G ORTEC to be defective in workmanship or materials within one year from the date of delivery EG amp G ORTEC s liability on any claim of any kind including negligence loss or damages arising out of connected with or from the performance or breach thereof or from the manufacture sale delivery resale repair or use of any item or services covered by this agree ment 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 EG amp G ORTEC fails to manufacture or deliver items called for in this agreement or purchase order EG amp G ORTEC s exclusive liability and buyer s exclusive remedy shall be release of the buyer from the obligation to pay the purchase price In no
7. EARITY Integral nonlinearity S 0 05 for Pos Neg and Recorder outputs CONTROLS START LEVEL Potentiometer selects voltage level at which a sweep begins range 1 to 10 V SPAN Potentiometer selects range from start level toward zero through which the output will be swept during a cycle range 1 to 10 V but limited to not more than the selected start level CHANNELS Switch selects the number of steps in a cycle settings are 16 32 64 128 and RAMP In RAMP position the number of steps is 1024 SWEEP TIME Switch selects total time for a full sweep cycle settings are 1 3 10 30 and 60 min SINGLE CYCLE AUTO RECYCLE Switch selects the type of automatic program SINGLE CYCLE Program consists of starting at the selected start level progressing toward zero across the adjusted span in the selected number of channel steps and resetting to the start level stopping at that point AUTO RECYCLE Program consists of the single cycle sequence above repeated after each reset to the start level FULL SWEEP STEP ADVANCE Switch selects either automatic or manual control FULL SWEEP Selects the automatic program cycle mode using the selected sweep time for step advances the cycle is initiated by pressing the start switch or by an advance input pulse STEP ADVANCE Selects manual or external control for step advances the cycle is initiated by pressing the start push button and each subsequent step is selected by eith
8. The 487 is compatible with the external baseline input requirements of all ORTEC single channei analyzers It can supply sufficient current to drive up to ten of these inputs in parallel The rear panel ADVANCE input is compatible with the BUSY output of the ORTEC 432 Printout Control This connection would be made when a preset timer or scaler in the printer loop is used to determine the amount of time that the 487 dwells on each channel The rear panel GATE output is compatible with the GATE inout of all ORTEC scalers and timers By making this connection the 487 would gate ON a timer for example only while a scan was being run i 4 OPERATING INSTRUCTIONS AND APPLICATIONS 4 1 GENERAL The 487 Spectrum Scanner provides a simple means of obtaining a strip chart recorder plot of counting rate versus energy information derived from an x ray or nuclear spectroscopy system Typicaily the output pulses from a linear amplifier which lie in a O to 10 V range the range for which the amplifier distribution of the am plifier output pulses accurately represents the energy spectrum of radiation incident upon the detector are separated and analyzed with a single channel analyzer by setting the analyzer window over one particular peak in the amplitude spectrum The analyzer output then will be a logic signal the count rate of which indicates the intensity of the energy represented by that setting of the analyzer lower level discriminator b
9. aseline All energies in the spectrum may be analyzed in this way by merely changing the setting of the lower level discriminator The 487 changes this setting automatically As the 487 steps the analyzer window through the range of interest the rate meter see Fig 4 1 will reflect the intensity of the energy being analyzed A visual display may be obtained with a strip chart recorder or an X Y plotter by driving the ordinate with the rate meter output voltage and the abscissa with the recorder s internal time base or with the output of the 487 for the plotter For explanation of the controls and connector data see Section 2 Specifications If the CHANNELS control is set to either the 16 32 64 or 128 position then the width of each channel can be found by dividing the range to be swept SPAN by the number of steps CHANNELS in the span The window width setting on the single channel analyzer should then be adjusted to be equal to the 487 channel width Refer to Section 4 2 of this manual for calibration procedures The recorder plot will be a histogram of the energy spectrum analyzed The RAMP position of the CHANNELS control is actually a simulated ramp consisting of 1024 equal steps In this position the analyzer window may be set to any width greater than 100 mV If an analog rate meter ORTEC 441 is used in the experiment then the plot will Detector ORTEC 441 Linear Ratemeter
10. e 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 will be repaired at the standard charge unless they have been grossly misused or mishandled in which case the user wili be notified prior to the repair being done A quotation will be sent with the notification 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 EG amp G ORTEC of the circumstances so that assistance can be provided in making damage claims and in providing replacement equipment if necessary CONTENTS WARRANTY PHOTOGRAPH DESCRIPTION SPECIFICATIONS INSTALLATION 3 1 General 3 2 Connection to Power 3 3 Connections to ORTEC Equipment OPERATING INSTRUCTIONS AND APPLICATIONS 4 1 General 4 2 Calibration Adjustments 4 3 Applications CIRCUIT DESCRIPTION MAINTENANCE INSTRUCTIONS LIST OF FIGURES Fig 4 1 Open Loop System Fig 4 2 Closed Loop System Digital Data Acquisition Page 0 WW Ww Q on Page E ADVANCE POS E AOS REP
11. either of two applications DRIVING ORTEC SCALER AND TIMER GATES Scanning Open circuit Not Scanning Shorted to ground for loads connected to positive supply voltages DRIVING RECORDER PEN DROP Scanning Shorted to ground for loads connected to negative supply voltages provides up to 50 mA Not Scanning Open circuit RECORDER OUT Three binding posts one isa common ground one is for a 10 mV range output and one is for a 100 mV range output monitors the POS output level 10 mV Range O to 10 mV positive with sweep slope negative Zo lt 1022 100 mV Range 0 to 100 mV positive with sweep slope negative Zo lt 10022 METER Front panel meter indicates instantaneous sweep level range O to 10 V TEST POINT Front panel test point for convenience in monitoring the instantaneous sweep level with an external voltmeter or oscilloscope i ORDERING INFORMATION POWER REQUIRED 24 V 110 mA 12 V 150 mA 24 V 35 mA 12 V 25 mA WEIGHT SHIPPING 6 Ib 2 72 WEIGHT NET 3 Ib 2 oz 1 42 kg DIMENSIONS Standard double width module 2 70 in by 8 714 in per TID 20893 Rev 3 INSTALLATION 3 1 GENERAL The 487 used in conjunction with ORTEC s 401 A 402A Bin and Power Supply is intended for rack mounting therefore vacuum tube equipment operating in the same rack must be sufficiently cooled by circulating air to prevent any localized heating of the all transistor circuitry used throughout the 487 The t
12. emperature of equipment mounted in racks can easily exceed the recommended maximum of 120 F 50 C unless precautions are taken 3 2 CONNECTION TO POWER The 487 contains no internal power supply and therefore must obtain power from a Nuclear Standard Bin and Power Supply such as ORTEC 401 402 It is recom mended that the bin power supply be turned off when modules are inserted or removed ORTEC instruments are designed so that the Bin Power Supply cannot be over loaded even when a full complement of modules is in the Bin However since this may not be true when the Bin contains modules of other than ORTEC design power supply voltages should be checked after the modules are inserted The 401A 402A has test points on the power supply control panel to monitor dc voltages Before operating the 487 check to see that all 401A 402A supply voltages 12 24 are within 0 5 V of their proper value When using the 487 outside the 401A 402A Bin and Power Supply be sure that the jumper cable used prop erly accounts for the power supply grounding circuits provided as recommended by the AEC in TID 20893 Rev Both high quality and power return ground connections are provided to ensure proper reference voltage feedback into the power supply and they must be preserved in remote cable installations Care must also be exercised to avoid ground loops when the module is operated outside the Bin 3 3 CONNECTIONS TO ORTEC EQUIPMENT
13. er pressing the start push button or furnishing an ex ternal advance signal through the rear panel START Push button switch initiates the program cycle and also provides manual advance for the step advance mode of operation STOP Push button switch interrupts the program cycle at any point the start switch can be used to continue the program without reset RESET Push button switch resets the output to the start level at any time CONNECTORS ADVANCE STOP RESET POS NEG and GATE All are type BNC UG 1094 U on rear panel RECORDER OUT Three banana plugs on rear panel INPUTS ADVANCE Accepts an external signal to start a cycle for the full sweep mode or to advance one channel after the cycle is initiated for the step advance mode pulse is 3 V rise time lt 1 ps width 200 ns min Zin gt 10008 pro tected to 25 V STOP OR function with front panel stop push button pulse is 3 V rise time S 1 ps width 200 ns min Zin gt 10002 protected to 25 V RESET OR function with front pane reset push button pulse is 3 V rise time s 1 us width 200 ns min Zin gt 10008 protected to 25 V OUTPUTS POS Positive bias level stepped sequentially from the selected start level 1 to 10 V through the adjusted span 1 to 10 V toward zero Zo lt 142 NEG Negative bias level stepped sequentially from the selected start level 1 to 10 V through the adjusted span 1 to 10 V toward zero Zo lt 182 GATE For
14. event shall EG amp G ORTEC be liable for special or consequential damages QUALITY CONTROL Befor being approved for shipment each EG amp G ORTEC instrument must pass a stringent set of quality control tests designed to expose any flaws in materials or workmanship Permanent records of these tests are maintained for use in warranty repair and as a source of statistical information for design tmprovements 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 EG amp G ORTEC must be informed either in writing or by telephone 615 482 4411 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 EG amp G ORTEC standard procedure requires that instruments returned for repair pass the same quality control tests that are used for new production instruments Instruments that are returned should be packed so that they will withstand normal transit handling and must be shipped PREPAID via Air Parcel Post or United Parcel Service to the nearest EG amp G ORTEC repair center The address label and the package should include the Return Authorization Number assigned Instruments being returned that are damaged in transit due to inadequat
15. he outputs of the gates go to a resistive ladder network which sums the weight of the successive stages of the counter in binary fashion This sum is fed into the input of the operational amplifier IC12 The output of C12 is a voltage which reflects the state of the counter with a resolution of 1 out of 1024 steps The eleven bit counter is automatically reset to zero state after the 1024th step by the network comprised of 039 and 040 R86 is a single turn potentiometer SPAN in the feed back loop of IC12 and thus determines the closed loop gain of that stage IC13A takes the output voltage of IC12 and amplifies it to a 10 V level for a START LEVEL setting R89 of 10 V or full scale This output NEG OUTPUT is present at the emitter of 042 042 is an emitter follower that provides the current handling cap ability of driving the external vaseline inputs of up to 10 ORTEC single channel analyzers IC13B and 043 invert the negative output voltage to provide a positive output voltage at CN 4 The binary counter may be driven in several different ways In the FULL SWEEP mode of operation it ts driven by the unijunction oscillator Q35 Q34 acts as a constant current source for charging the capacitor C13 The oscillation frequency is determined by C13 the magnitude of its charging current and the trigger voltage at the emitter of O35 044 serves as a current sump to stop the oscillator whenever a STOP has been made IC18A and IC18B form a
16. ng on the front panel markings The procedure is as follows Depress the RESET push button Set the START LEVEL at full scale full clockwise Set the FULL SWEEP STEP ADVANCE switch to STEP ADVANCE Set the CHANNELS control to 16 Manually depress the START push button 17 times This places the output in channel zero The SPAN control can now be adjusted so that the voltage at the monitor test point is 0 00 The 487 is now calibrated for a full range sweep of 10 00 V This procedure may be used for any settings on the START LEVEL and SPAN controls when it is desired to sweep between two precisely known voltage levels 4 3 APPLICATIONS OPEN LOOP SYSTEM Figure 4 1 shows a system for obtaining a recorder plot of count rate vs energy using the 487 for sweeping the window of the single channel analyzer through the spectrum derived from the detector This system is open loop in the sense that for an energy scan operation of the 487 is not controlled by the results of the data being collected That is there is no feedback to alter the operation of the 487 as the scan progresses CLOSED LOOP SYSTEM Figure 4 2 shows a system for obtaining a histogram plot of count rate vs energy using the 487 for stepping the window of the single channel analyzer through the spec trum derived from the detector In this digital data acquisition system data are collected for a preset time selected by the ORTEC 434 Digital Rate Meter at one energy A
17. o volts with a reset to the start level after the selected number of steps or channels has been generated The 487 can be set for a single cycle of automatic programming or for automatic recycling When it is set for full sweeo operation the automatic program includes an adjusted dwell time per channel which results in 16 to 1024 equal time increments within the selected total sweep time 1 to 60 min When it is set for step advance dwell time is exclusively a function of the interval between advance pulses through a rear panel connector and this permits the system to be used for studies of correlation with mechanical movements or other conditions which can require apertodic stepping A cycle once it has been started can be stopped manually or electronically and can be restarted from the point of interruption or can be reset to the start level A recorder output included on the rear panel to monitor the baseline output level is furnished in addition to a front panel meter and a convenient test point The test point can be used for critical adjustments of both start level and span The recorder output can be used as the X drive in an X Y recorder it is not required for a strip chart recorder A rear panel gate output may be used to control other instruments in the counting system according to the scanning and nonscanning intervals programmed in the 487 2 SPECIFICATIONS PERFORMANCE SWEEP TIME ACCURACY 35 OUTPUT NONLIN
18. r Return Ground Reset Scaler Gate Reset Auxiliary Coaxial Coaxial Coaxial 115 volts ac Neut High Quality Ground Ground Guide Pin Pins marked are installed and wired in ORTEC 401A and 4018 Modular System Bins Pins marked and are installed and wired in EG amp G ORTEC HEP M250 N and M350 N NIMBINS Al 8 BR a y Ro ds a Be 52 53 N i A Theo PR Ole THRU QIB SAME AS B 913 THRU SAME B SAME AS B L_ _R36 THR R39 SER GEN nan eee hal q mw a2 Inc SAME ASB DE l esz meo RAS NOA a ll N G22 THRO 924 R52 SAME 48 B _ R48 THRU RSI j 1 rer I l 925 THRU i ps i same ASB Mio Tieu A O ae ee a 928 THEY ao as SAME A6 B 10K e F grev I RGB Py R70 7 3 REG asi i IK pal l R69 i 1 22K i ER ay 8 cs 6 8 HE ll R84 464 Jo 27K 7 cw ee Res START R90 LEVEL 1o IR IT ER 12 R17 9 180 AUTO Ri REC 43x EN D L D R75 S eas SINGLE 43K CYCLE RBI IQOn H2Vo E 3 6V E ell bow sio Te al J C POWER SUPPLY BEN An k if i D e EF ar 8 A si CHANNELS N gt i pue ia 63 1 7 STEP H ADVANCE zus 8 05 sk tf re 3 AIDA 2 Ic 2 1 188 s re Me
19. t the end of the preset time interval a BUSY signal is generated from the printout control unit the rate meter is automatically reset for a new data taking interval and the 487 output is moved to the next level The data taken at each energy setting may be printed out on computer compatible punched paper tape with the Teletype 33 ASR E ORTEC o 109PC 53 Preamp a 200476 Fig 4 2 Closed Loop System Output DATEC ORTEC 487 432 Spectrum Printout Scanner Control L Recorder be DA AA a FDA re Analyzer Output LE Strip Chart Recorder Ratemeter Neg or X Plotter ASR 33 TELETYPE Digital Data Acquisition 5 CIRCUIT DESCRIPTION The 487 is basically a programmable voltage staircase generator The staircase output is obtained by sequencing a digital to analog converter from a selected starting voltage START LEVEL through a number of steps selected by the CHANNELS control IC1 through IC11 comprises an eleven bit binary counter The outputs of the successive binary stages of this counter are fed into eleven gates comprised of O1 through 033 Q1 2 and Q3 make up the basic gate which is duplicated for the successive stages The output of the gate junction of emitters of Q2 and Q3 is either at ground potential or at a positive 12 V level depending upon the state of the driving flip flop in the binary counter T
20. y stage of the binary counter The first four stages or the four least significant bits will not contribute to the output staircase voltage therefore the output will step 1024 24 automatically reset Once the start reset flip flop has been set with a START then all subsequent depressions of the START push button will cause the output staircase voltage to move one step via the gate IC17A through its range in or 64 equal steps and then IC17B and 041 comprise a one shot multivibrator for reshaping the RESET input pulse into a pulse sufficiently long to assure the resetting of all the associated logic circuitry The front panel RESET push button is essentially connected in parallel with this input The GATE output circuitry 037 Q38 and 045 is driven from the output of the start reset flip flop con sisting of IC16A and IC16B When a start has been made and pin 6 of IC16B goes low O38 becomes saturated and Q45 is turned off When the start reset flip flop has been given a reset input then 038 turns off and 045 be comes saturated due to pin 6 of IC16B going high This means that while the 487 is scanning should the GATE output be connected to the GATE input of an ORTEC scaler or timer then that scaler or timer will be allowed to count due to its GATE input going high Resetting the 487 pulls this gate low and inhibits furtner counting in the scaler or timer Should the GATE output of the 487 be connected to the chart advance input
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