Model 474 Timing Filter Amplifier Operating and Service Manual
Contents
1. OOU Suber Aerie CLIO LOT Aa ai 4 LS DIESLE LIF ALi CARTER SAMPLE LIA 7 MLA A AITU IED L fiter PIBE ML TUNEZ ez L Aur LASE L TIBE AEE E lied s tte livia SLT CERA 4 LLU LYMLT HO USE PUMA 72 SEU Of FET Leta ACCORDI tiie SUL IZ COMSART TIA BASED PRL pri SETI ZL LAS TH UAT SIDO SOLU SE 4 Sige CE J ALLE DLAK MECA ag CR USCA TL LIVUERJ ER LVL Sirake NL REGA When wig the IPR wt lit the i VEE the IZA GOUL Pel eye Lat bid rel SIT DORA tether LADO tit la CARITAS Fig 6 2 Nanosecond Decay Time Fluorescence Spectrometer System 10 10 Intensity N yy 10 10 Time Fig 6 3 Lifetime Spectrum of Quinine Sulfate in Sulfuric Acid Bin Module Connector Pin Assignments for Standard Pin ONOoaARWBND 16 17 18 19 20 21 22 Function 3 V 3 V Spare Bus Reserved Bus Coaxial Coaxial Coaxial 200 V dc Spare 6 V 6 V Reserved Bus Spare Spare Reserved 12 V 12 V Spare Bus Reserved Bus Spare Spare Reserved Pin 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Nuclear Instrument Modules per DOE ER 0457T Function Reserved Reserved Reserved Spare Spare 24 V 24 V Spare Bus Spare Spare 117 V ac Hot Power Return Ground Reset Scaler Gate Reset Auxiliary Coaxial Coaxial Coaxial 117 V ac Neutral High Quality Ground Ground Guide Pin Pins marked are installed and2. High Voltage Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product SAFETY WARNINGS AND CLEANING INSTRUCTIONS DANGER Opening the cover of this instrument is likely to expose dangerous voltages Disconnect the instrument from all voltage sources while it is being opened WARNING Using this instrument in a manner not specified by the manufacturer may impair the protection provided by the instrument Cleaning Instructions To clean the instrument exterior e Unplug the instrument from the ac power supply e Remove loose dust on the outside of the instrument with a lint free cloth e Remove remaining dirt with a lint free cloth dampened in a general purpose detergent and water solution Do not use abrasive cleaners CAUTION To prevent moisture inside of the instrument during external cleaning use only enough liquid to dampen the cloth or applicator e Allow the instrument to dry completely before reconnecting it to the power source vi m 47 ag TIMING Y FILTER AMP COARSE GAIN x4 x2 4 xi i ORTEC MODEL 474 TIMING FILTER AMPLIFIER 1 DESCRIPTION 1 1 GENERAL The ORTEC 474 Timing Filter Amplifier is a NIM standard module for use where a wide band fast variable RC filter amplifier with high drive and variable gain is needed Features of the 474 include a wide gain control range separately selectable RC integra
3. alte le Dk 2 31 GENERA Loc la tanda 2 3 2 CONNECTION TO POWER 0000500 rs ee ee ee ele de be pa e da be eb ad de a 2 3 3 INPUT OUTPUT CONNECTIONS 1 0 0 0 0 00 2 4 OPERATING INSTRUCTIONS 0 0 cette ttn eee 3 5 CIRCUIT DESCRIPTION ooo 3 6 MAINTENANCE seasgan ee bed iden eb de e445 ele wee oe ke degen eh a de ats 4 6 1 CORRECTIVE MAINTENANCE 0 00 eee 4 6 2 FACTORY SERVICE cutre ie Peay palit lee ted oye ele alee See Bed wi odie 4 6 3 GENERAL te iss dard Sra athens Gat at ea aren Sted aden anes 4 6 4 CONSTANT FRACTION TIMING WITH GERMANIUM DETECTORS 4 6 5 NANOSECOND FLUORESCENCE SPECTROMETRY 00 0c ce eee ee eee 5 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 Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product In addition the following symbol may appear on the product N ATTENTION Refer to Manual AN DANGER
4. output voltage amplifier consisting of transistors Q9 through Q20 and associated resistors and capacitors has a voltage gain of approximately 5 A complementary Darlington output stage is used to provide good bipolar drive capability Potentiometer R100 is a factory adjusted balance control for the two halves of the complementary Darlington output stage Integrated circuit IC1 senses the output at CN2 and acts in the dc feedback loop to force the output to zero IC1 is connected as an integrator with a time constant of approximately 150 us corresponding to about 1 kHz The NIM power connector includes circuits that accept 12 V and 24 V These input power levels are filtered and are used internally in the circuits of the 474 The four levels are also furnished through the rear panel Preamplifier Power connector CN4 and can be used as the power source for an associated ORTEC preamplifier 6 MAINTENANCE 6 1 CORRECTIVE MAINTENANCE The ORTEC 474 should require no regular maintenance other than replacement of components that have failed due to age Always ensure that the replacement components are equivalentto the original parts No internal trimming or adjustment is necessary for the 474 To aid in the identification of a malfunctioning component typical dc voltages are listed in Table 6 1 Note that these are typical values and may vary from one unit to another without indicating a fault 6 2 FACTORY SERVICE This
5. reliable timing data possible at even the FW 1 100 M level The SRT circuitry in the constant fraction discriminator can provide improved timing resolution by rejecting those logic pulses that result from leading edge timing in the instrument Since the input signals that cause leading edge walk represent valid energy information use of the SRT circuitry results in a loss in the counting efficiency of the system A system for measuring the lifetimes of excited states at extremely low energies is similar to the system shown in Fig 6 1 In this configuration the coaxial Ge Li detector and preamplifier are replaced with a Ge Li low energy photon spectrometer LEPS detector and preamplifier Q18E 29 mV Q19B 8 65V Q19C 11 70 V Q20B 8 65 V Q20C 11 70 V IC1 2 2 6 mV IC1 3 2 2 mV IC1 12 V IC1 70 mV IC1 12V A1 100 mV 120 mV 0 50 V 17 mV 0 mV 11 5 V 5 8 V OV 0 66 V 11 7V 17 mV 1 0mV 0 8 V 40 mV 56 mV 11 5 V 5 8 v OV 0 77 V 0 77 V 11 7 V annan NO A D UL O A ZA A A A a SHS OODOONODORWNHHOANDNARWN A1 A1 A1 A1 A1 A1 A1 A1 A1 A2 A2 A2 A2 A2 A2 A2 A2 A2 A2 A2 6 5 NANOSECOND FLUORESCENCE SPECTROMETRY The ORTEC 9200 Nanosecond Fluorescence Spectrometer is used in lifetime measurements of excited molecular states In the specific application where the molecular structure is studied the experimenter seeks to verify a complex model
6. wired in ORTEC s Model 4001A and 4001C Modular System Bins
7. 50 for this purpose The shaping time constants that select integration and differentiation circuits in the 474 can be set to normalize a pulse rise and decay time to optimize timing measurements In addition to these basic functions the 474 can also be used to invert the pulse polarity if desired and to correct for the pole zero effect that is provided from the preamplifier system There are no typical control settings that can be suggested for operation since each application of the 474 will require a different combination of functions After the system has been installed use an oscilloscope to observe the waveforms at the input and output of the 474 and adjust its controls to optimize its operation considering the functions that are required of it Generally speaking the Integrate time constant can be selected so that the rise time of the output pulses is normalized at a rate that is slower than the rise times of the input pulses This function is of greatest value when the pulses originate in a large detector so that they generate a wide variety of rise times and are difficult to observe for timing measurements The Differentiate time constant is also selectable and determines the total interval before the pulse returns to the baseline and allows a new pulse to be observed The combination of integration and differentiation time constants also contributes to the amount of electronic noise that is seen in the system so the resulting w
8. Printed in U S A Model 474 Timing Filter Amplifier Operating and Service Manual ORTEC Part No 733370 Manual Revision D 1003 Advanced Measurement Technology Inc a k a ORTEC a subsidiary of AMETEK Inc WARRANTY ORTEC warrants that the items will be delivered free from defects in material or workmanship ORTEC makes no other warranties express or implied and specifically NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ORTEC s exclusive liability is limited to repairing or replacing at ORTEC s option items found by ORTEC to be defective in workmanship or materials within one year from the date of delivery ORTEC s liability on any claim of any kind including negligence loss or damages arising out of connected with or from the performance or breach thereof or from the manufacture sale delivery resale repair or use of any item or services covered by this agreement or purchase order shall in no case exceed the price allocable to the item or service furnished or any part thereof that gives rise to the claim In the event ORTEC fails to manufacture or deliver items called for in this agreement or purchase order ORTEC s exclusive liability and buyer s exclusive remedy shall be release of the buyer from the obligation to pay the purchase price In no event shall ORTEC be liable for special or consequential damages Quality Control Before being approved for shipment each ORTEC instrument mu
9. aveforms should be considered from each of these points of view and adjusted for optimum results When the shaping time constants impose considerable changes in the input waveform the nominal gain which is the product of the Coarse and Fine control settings may be degraded somewhat This is not normally a problem since the gain is constant even though it may be less than the nominal settings indicate 5 CIRCUIT DESCRIPTION The front panel toggle switch S1 selects a resistance network for Invert or a circuit through QI and Q2 for Non invert for pulses of either polarity and the pulses are then furnished into the differentiation network at S2 If S2 is set at Out the input pulse is coupled through R34 to the input of Al The pole zero adjustment R30 does not provide any effect for the Out setting of S2 If S2 is set at any of its other five positions the input pulse is coupled through a capacitor that is in parallel with a portion of the signal furnished through the pole zero circuit and provided to the input of A1 Amplifier A1 is an ORTEC Hybrid circuit type HBA0106 that includes Coarse Gain control S3 The amplified output at pin 5 of A1 is furnished to the integration network at the input to A2 which is another type HBA0106 ORTEC Hybrid circuit Amplifier A2 has a gain that is adjusted by Fine Gain control R64 The output of A2 is furnished to the base of 09 which is the input of the output voltage amplifier The
10. e and decay time for compatibility with the application requirements The linear output pulses can be either uni polar or bipolar depending on the type of input pulses that are furnished to the 474 When the front panel toggle switch selects Invert the output is the opposite polarity to the input or when the toggle switch selects Non invert the polarities are the same The 474 is capable of driving a 500 load up to 5 V with no degradation of the performance specifications The ORTEC 474 Timing Filter Amplifier is a NIM standard single width module the front panel measures 1 35 by 8 714 in which is in accordance with TID 20893 Rev It is intended for installation and operation in a standard enclosure such as the ORTEC 4001 4002 Series of Bins and Power Supplies The module accepts all of its required operating power f rom the power supply that is attached to the bin 2 SPECIFICATIONS 2 1 PERFORMANCE INPUT AMPLITUDE RANGE 0 to 1V linear signal 0 to 5 V offset maximum input 5 V total OUTPUT AMPLITUDE RANGE 0 to 5 V linear onto a 500 cable and load RISETIME lt 10 ns with filter Out or 2 2 1 for other Integrate settings NOISE For maximum gain rms noise referred to the input is lt 10 uV witht T 200 ns or lt 50 uV with filter Out measurements made with an HP 3400A true rms meter NONLINEARITY lt 0 05 at mid band frequency over 5 V range TEMPERATURE INSTABILITY DC Level lt 25 uV C refer
11. ed signal through Z lt 10 dc coupled Amplitude 0 to 5 V risetime and decay time controlled by Integrate and Differentiate filter settings PREAMP POWER Rear panel standard ORTEC power connector Amphenol type 17 10090 2 5 ELECTRICAL AND MECHANICAL POWER REQUIRED 24V 60 mA 24V 40 mA 12V 145 mA 12 V 165 mA DIMENSIONS NIM standard single width module 1 35 by 8 714 in per TID 28093 Rev 3 INSTALLATION 3 1 GENERAL The 474 operates on power that must be furnished from a nuclear standard bin and power supply such as the ORTEC 4001 4002 Series The bin and power supply is designed for relay rack mounting If the equipment is to be rack mounted be sure that there is adequate ventilation to prevent any localized heating of the components that are used in the 474 The temperature of the equipment mounted in racks can easily exceed the maximum limit of 50 C 823 K unless precautions are taken 3 2 CONNECTION TO POWER The 474 contains no internal power supply and must obtain the necessary dc operating power from the bin and power supply in which it is installed for operation Always turn off power for the power supply before inserting or removing any modules ORTEC modules are designed so that a full complement of modules installed in the bin will not overload the NIM standard power supply Since however this may not be true when the bin contains modules other than those of ORTEC design the dc power
12. ese additional features provide useful functions in most of the circuits where pulse shaping is necessary Each application for the 474 will require a different combination of the data enhancement parameters that are available Use each as required in the specific application 6 4 CONSTANT FRACTION TIMING WITH GERMANIUM DETECTORS Figure 6 1 is a block diagram of a gamma gamma coincidence system that can be used for timing with germanium detectors In this system the TPHC start channel uses a fast plastic scintillator and the stop channel uses a coaxial germanium detector Excellent timing spectra have been obtained by combining the pulse shaping available with the 474 together with the use of the slow rise time SRT reject circuitry in the constant fraction discriminator Table 1 Typical DC Voltages NONINV Mode DIF and INT switches set to Out fine gain 2 coarse gain 1 Q1B 2 7 mV Q1E 0 6 V Q1C 12 0 V Q2B 45 mV Q2C 5 90 V Q3E 5 35 V Q4B 6 76 V Q4E 7 40 V Q5B 7 40 V Q6E 7 30 V Q7B 14 50 V Q7E 13 95 V Q8E 14 56 V Q9B 90mV Q9E 0 73V Q8C 9 25 V Q10B 7 60 V Q10E 8 25 V Q11B 8 20 V Q11C 12 0V Q12E 8 20 V Q12C 1 27 V Q13E 1 21 V Q13C 1 25 V Q14E 9 85 V Q14C 1 31 V Q15E 0 66 V Q15C 8 0 V Q16E 25 mV Q17E 0 68 V Q17C 8 0 V The SRT circuitry is most effective when used with a wide dynamic range of energies lt can provide dramatic improvement in timing resolution below the FWHM level and makes
13. instrument can be returned to the ORTEC factory for service and repair at a nominal cost The ORTEC standard procedure for repair ensures the same quality control and checkout that are used for a new instrument Always contact ORTEC Customer Service before sending in an instrument for repair to obtain shipping instructions and so that the required Return Authorization Number can be assigned to the unit This number should be written on the address label and on the package to ensure prompt attention when it reaches the factory 6 3 GENERAL The most important function that is served by the 474 Timing Filter Amplifier is pulse shaping This is especially important when using the output from a large volume detector with a wide range of charge collection times for its output pulses and attempting to obtain timing information from these nonuniform pulses By adjusting the pulse rise time with the 474 to an interval that is longer than any of the input rise times the 474 output pulses will have the advantage of uniformity The pulse decay time constant is also selectable so that the operator can compromise between pulse pair resolution time and system noise as shorter time constants are used pulse pair resolution time is shortened at the expense of an increase in noise Other functions that are also included in the 474 area linear amplification of small pulses of either polarity polarity control and adjustable pole zero cancellation Th
14. levels should be checked after all of the modules have been installed The ORTEC 4001 4002 Series Bins Power Supplies have convenient test points on the power supply control panel to permit monitoring these dc levels 3 3 INPUT OUTPUT CONNECTIONS The input impedance of the 474 is about 1000 and provides a suitable termination for cable with a characteristic impedance of 930 It the cable with a characteristic impedance of 500 use a BNC Tee at the 474 Input to accommodate the cable and a 1000 terminator the terminator and the input impedance which are in parallel will then match the 500 cable impedance The low output impedance of the 474 requires that the output cable be terminated by the characteristic impedance of the cable at its remote end This can be accomplished at the input of a high input impedance instrument or by using an instrument with an input impedance equal to the impedance of the cable Both driving end and receiving end coaxial line termination is recommended for long cables although this reduces the driving amplitude by 50 4 OPERATING INSTRUCTIONS Either of two functions or both may be furnished by the ORTEC 474 Timing Filter Amplifier depending on the details of the circuit in which it is installed It may be used to linearly amplify a small amplitude range into one that is better suited to the requirements of a subsequent instrument in the system the gain can be set at any level from X2 through X2
15. of a particular molecule or to determine how a particular molecule is altered by its surroundings This type of experiment requires that the total efficiency the exact energy and the complete time function involved in the de excitation of an electronic state be known so that the experimental results can be fit precisely to a model Figure 6 2 shows the 9200 System and Fig 6 3 shows the detailed lifetime characteristics of a 0 1 N solution of quinine sulfate in sulfuric acid that was excited with impulses of light at approximately 340 nm with the 9200 System The quantity of information available from such a lifetime measurement is illustrated by this set of data 456 HIGH VOLTAGE POWER SUPPLY 459 DETECTOR BIAS SUPPLY 1 by 1 in KL236 22Na Source RCA 8575 PM TUBE GelLi COAXIAL DETECTOR 120 4 PREAMPLIFIER 473A 473A 474 113 425A SCINTILLATION apace BANESECOND CONSTANT TIMING PREAMPLIFIER DELAY FRACTION FILTER DISCRIMINATOR DISCRIMINATOR AMPLIFIER 457 460 414A 460 551 TIME TO 551 DELAY LINE FAST DELAY LINE AMPLIFIER TIMING SCA PuLSEHEIONT COINCIDENCE TIMING SCA AMPLIFIER 62408 MULTICHANNEL ANALYZER Fig 6 1 Gamma Gamma Coincidence System Using a Plastic Scintillator and a Large Ge Li Coaxial Detector
16. red to the output Gain lt 0 06 C OPERATING TEMPERATURE RANGE 0to50 C 273 to 323 K 2 2 CONTROLS COARSE GAIN Front panel 6 position switch to select X1 X2 X4 X6 X10 or X20 gain factor FINE GAIN Front panel single turn potentiometer continuously adjustable from X2 to X12 5 POLE ZERO ADJUST Front panel screwdriver adjustment to cancel the pole associated with the input signal such as that derived from the preamplifier clipping network DIFFERENTIATE Front panel 6 position switch selects a differentiation time constant to control the decay time of the pulse settings select Out equivalent to 150 us 20 50 100 200 or 500 ns INTEGRATE Front panel 6 position switch selects an integration time constant to control the risetime of the pulse settings select 20 50 100 200 or 500 ns or Out equivalent to 10 ns Note With Diff and Int switches both at Out passband is typically 1 kHz to 35 MHZ INVERT NONINVERT Front panel toggle switch selects inversion or noninversion of the input signal polarity for the polarity of the output signal 2 3 INPUT INPUT Front panel BNC connect or accepts input pulses of either polarity amplitude O to 1 V protected to 6 V dc and to 100 V at 10 duty cycle integrated over 1 second impedance 1000 dc coupled Accepts a 5 V dc offset maximum input signal plus offset limited to 5 V 2 4 OUTPUTS OUTPUT Front panel BNC connector furnishes the shaped and amplifi
17. rranty should follow the same procedure and ORTEC will provide a quotation Damage in Transit Shipments should be examined immediately upon receipt for evidence of external or concealed damage The carrier making delivery should be notified immediately of any such damage since the carrier is normally liable for damage in shipment Packing materials waybills and other such documentation should be preserved in order to establish claims After such notification to the carrier please notify ORTEC of the circumstances so that assistance can be provided in making damage claims and in providing replacement equipment if necessary Copyright 2003 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 CONTENTS WARRANTY e sicetaa pel al paa E A baleen 4 ped e Deen O A a beg i SAFETY INSTRUCTIONS AND SYMBOLS occocccccco eeee iv SAFETY WARNINGS AND CLEANING INSTRUCTIONS 0 0 00 c eee eee v 1 DESCRIPTION idp A A ae A E 1 1 GENERAL 000 drid a A AS A A e idea 1 2 SPECIFICATIONS itd at Mad a ot a O A ete a 1 21 PERFORMANCE ovario a Grog alate 1 22 CONTROLES poi bos rr ts pe teeth ge eee lp ab be a Ger CO ga Rd a a 2 23 INRUI sara dia iva a ba boa e 2 24 QUTRUTS a eile A A A a da 2 2 5 ELECTRICAL AND MECHANICAL 00 0 c eect tenes 2 Se INSTALLATION a a a ea hg A a
18. st 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 improvements Repair Service If it becomes necessary to return this instrument for repair it is essential that Customer Services be contacted in advance of its return so that a Return Authorization Number can be assigned to the unit Also ORTEC must be informed either in writing by telephone 865 482 441 1 or by facsimile transmission 865 483 2133 of the nature of the fault of the instrument being returned and of the model serial and revision Rev on rear panel numbers Failure to do so may cause unnecessary delays in getting the unit repaired The ORTEC standard procedure requires that instruments returned for repair pass the same quality control tests that are used for new production instruments Instruments that are returned should be packed so that they will withstand normal transit handling and must be shipped PREPAID via Air Parcel Post or United Parcel Service to the designated ORTEC repair center The address label and the package should include the Return Authorization Number assigned Instruments being returned that are damaged in transit due to inadequate packing will be repaired at the sender s expense and it will be the sender s responsibility to make claim with the shipper Instruments not in wa
19. te and differentiate time constants in the nanosecond region pole zero compensation and drive capability sufficient for use with 500 or 1000 systems The input signals are dc coupled into an impedance of about 1000 The acceptable amplitude range for the linear input to retain its linearity is O to I V The 474 can operate with an input dc offset where the maximum total input signal range including the offset does not exceed the limits of 5 V Input signals may be either positive or negative unipolar or they can be bipolar with either a positive or negative lobe leading The output polarity can be switch selected to either duplicate or invert the input polarity Protection is provided for input voltages of up to 100 V at a 10 duty cycle integrated over 1 second The gain for midband frequencies can be set at any value from X2 through X250 using six coarse gain settings and a fine gain control which is a single turn potentiometer The gain factors are selected to provide range overlap and to assure continuously adjustable gain control throughout the full range Two 6 position switches permit the separate selection of RC integrate and RC differentiate time constants The integrate time constant can be selected from 10 ns switch set at Out through 500 ns The differentiate time constant can be selected from 20 ns through 500 ns or when set at Out at 150 us Thus the input pulses can be reshaped to provide a consistent risetim
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