ORTEC 863 Service manual

Model 863
Quad Timing Filter Amplifier
Operating and Service Manual
Printed in U.S.A. ORTEC®Part No. 733960 0411
Manual Revision C

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
nootherwarranties,expressorimplied,andspecificallyNOWARRANTYOFMERCHANTABILITYORFITNESS
FOR A PARTICULAR PURPOSE.
ORTEC’s exclusive liability is limited to repairing or replacing at ORTEC’s option, items found by ORTEC to be
defective in workmanship or materials within one year from the date of delivery. ORTEC’s liability on any claim
of any kind, including negligence, loss, or damages arising out of, connected with, or from the performance or
breach thereof, or from the manufacture, sale, delivery, resale, repair, or use of any item or services covered by
this agreement or purchase order, shall in no case exceed the price allocable to the item or service furnished or
any part thereof that gives rise to the claim. In the event ORTEC fails to manufacture or deliver items called for
in this agreement or purchase order, ORTEC’s exclusive liability and buyer’s exclusive remedy shall be release
of the buyer from the obligation to pay the purchase price. In no event shall ORTEC be liable for special or
consequential damages.
Quality Control
Before being approved for shipment, each ORTEC instrument must pass a stringent set of quality control tests
designed to expose anyflaws 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
beinformed, either in writing,bytelephone [[phone]]or byfacsimile transmission[[phone]],of the
nature of the fault of the instrument being returned and of the model, serial, and revision ("Rev" on rear panel)
numbers. Failure to do so may cause unnecessary delays in getting the unit repaired. The ORTEC standard
procedure requires that instruments returned for repair pass the same quality control tests that are used for
new-production instruments. Instruments that are returned should be packed so that they will withstand normal
transit handling and must be shipped PREPAID via Air Parcel Post or United Parcel Service to the designated
ORTEC repair center. The address label and the package should include the Return Authorization Number
assigned. Instruments being returned that are damaged in transit due to inadequate packing will be repaired at
the sender's expense, and it will be the sender's responsibility to make claim with the shipper. Instruments not
in warranty should follow 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
fordamageinshipment.Packingmaterials,waybills,andothersuchdocumentationshouldbepreservedinorder
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 © 2011, 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.

iii
CONTENTS
WARRANTY........................................................................... ii
SAFETY INSTRUCTIONS AND SYMBOLS ..................................................iv
SAFETY WARNINGS AND CLEANING INSTRUCTIONS ....................................... v
1. INTRODUCTION ..................................................................... 1
2. SPECIFICATIONS ................................................................... 2
2.1. PERFORMANCE ................................................................ 2
2.2. CONTROLS .................................................................... 2
2.3. INPUT ........................................................................ 2
2.4. OUTPUT....................................................................... 2
2.5. ELECTRICALANDMECHANICAL................................................... 2
3. INSTALLATION...................................................................... 3
4. CIRCUIT DESCRIPTION .............................................................. 3

iv
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:
ATTENTION – Refer to Manual
DANGER – High Voltage
Please read all safety instructions carefully and make sure you understand them fully before attempting to
use this product.

v
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.
CAUTION To prevent moisture inside of the instrument during external cleaning, use only enough liquid
to dampen the cloth or applicator.
SAFETY WARNINGS AND CLEANING INSTRUCTIONS
Cleaning Instructions
To clean the instrument exterior:
! Unplug the instrument from the ac power supply.
! 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.

vi

1
ORTEC MODEL 863
QUAD TIMING FILTER AMPLIFIER
1. INTRODUCTION
TheORTECModel863QuadTimingFilterAmplifier
incorporates four separate timing filter amplifiers in
a single-width NIM module. This design provides a
compactand cost-effectivesolutionfor experiments
where timing is required on a number of detectors.
TogetherwithanORTECModel934QuadConstant
Fraction Timing Discriminator, the Model 863 can
provide optimum timing for up to four germanium
detectors. The unit can also be used for timing with
other solid-state detectors, or as a general purpose
wide-band amplifier with selectable bandwidth.
The signals from germanium or silicon detectors at
the preamplifier output are not always optimum for
achieving good timing resolution. Before
presentation to a timing discriminator, the signals
normally require amplification with a wide-band
amplifier, and they may need additional pulse
shaping to minimize the noise contribution to the
time resolution. The Model 863 provides a flexible
approach in serving these two functions in order to
handle a wide variety of solid-state detector types.
The gain can be selected as either inverting or
noninverting and is adjustable over the nominal
range of 2 to 250. The fine gain is adjustable from 2
to 50 using afront-panel screwdriver potentiometer,
while a printed wiring board (PWB) jumper selects
a coarse gain of either 1× or 5×. The output will
drive a 50
Ω load to ±5 V with good linearity. This
ensures that the full
! 50 mV to ! 5 V dynamic range
of a constant fraction timing discriminator can be
used. Excellent dc stability of the output is
maintained by a continuous baseline restorer.
Several means of bandpass limiting are included to
achieve the pulse shaping that yields the optimum
time resolution. With alljumpers in the Out position,
the Model 863 is a wide-band amplifier with an
output rise time <10ns. To reduce low frequency
noise and shorten the output pulse width, the CR
differentiation time constant can be decreased from
0.1 ms (Out position) to 200 ns using a PWB
jumper.Alternatively,twofront-panelconnectorscan
be employed (using a 50
Ω coaxial cable) to add
delay line clipping. This results in a more abrupt
termination of the output pulse duration while
reducing low frequency noise. Both the CR
differentiation and the cable clip can be used
togethertoyieldabipolaroutputsignalforfast,zero-
crossing timing.
In some cases it is beneficial to select a 50 ns RC
integration time constant using the PWB jumper
provided for that purpose. This reduces the high
frequencynoisewhileslowingtheoutput rise time to
110 ns.
In addition to the two standard jumper selections
incorporated into each of the Differentiation and
Intergration controls, a third position is provided for
both jumpers. By adding the appropriate
components to each third position, it is possible for
the user to select a customized set of integration
and differentiation time constants.
In order to ensure that the output pulse returns to
baseline as quickly as possible, the differentiation
circuitincludesafront-panelpole-zerotrimmer.This
control permits compensation for the preamplifier
decay time constant.
Each section of the Model 863 have five sets of
PWB jumpers to control the various functions of the
unit. These jumpers are accessible by removing the
left side panel of the module.

2
2. SPECIFICATIONS
2.1. PERFORMANCE
INPUT SIGNAL AMPLITUDE RANGE 0 to ±1.0 V
ac signal; 0 to ±2 V dc offset; maximum input ±2 V
signal plus offset.
OUTPUT AMPLITUDE RANGE 0 to ±5 V linear
into a 50
Ω load. Output dc-coupled with dc offset
<±10mV.
RISE TIME <10 ns with Integration and
Differentiation time constants set to Out, or
. 2.2 τ
forotherIntegrationsettingsandDifferentiationOut.
CROSS TALK <0.01% from any output to any
input measured at maximum gain with Integration
and Differentiation time constants set to Out.
NOISE For maximum gain, rms noise referred to
the input <50
μ V with Integrationand Differentiation
set to Out; measured using a Hewlett-Packard
3400A true rms meter.
INTEGRAL NONLINEARITY <±0.5% over ± 5 V
into a 50
Ω load.
TEMPERATURE SENSITIVITY dc level
<±10
μ V « E C referred to the output. Gain sensitivity
<±0.05%
« E C.
OPERATING TEMPERATURE RANGE 0
E C to
50
E C.
2.2. CONTROLS
Each section of the Model 863 Quad Timing Filter
Amplifier has separate controls for Coarse Gain,
Fine Gain, P/Z, Differentiation, and Integration time
constant.
COARSE GAIN PWB jumper selectable for
nominally 1× or 5×. Gain is reduced by a factor of 2
when using cable clip. The model 863 is shipped
with this jumper in the 5× position.
FINEGAIN Front-panelscrewdriverpotentiometer
continuously adjustable from 2 to 50 (nominal).
P/Z Front-panel screwdriver adjustable
potentiometer to adjust pole-zero cancellation for
decay time constants from 25
μ s to 4 .
DIFFERENTIATION Time constant PWB jumper
selectable as either Out (equivalent to 0.1 ms) or
200 ns. A third position is available for custom
modification. The Model 863 is shipped with this
jumper in the Out position.
INTEGRATION Time constant PWB jumper
selectable as either Out or 50 ns. A third position is
available for custom modification. In the Out
position, the 10% to 90% rise time is <10 ns. The
Model 863 is shipped with this jumper in the Out
position.
INVERT/NONINVERT PWB jumper selectable to
Invert or Noninvert the Output signal relative to the
Input signal. The Model 863 is shipped with this
jumper in the Noninvert position.
2.3. INPUT
INPUT Positive or negative polarity selectable with
a PWB jumper; amplitude 0 to ±1 V ac signal; 0 to
±2 V dc offset; maximum input ±2 V signal plus
offset. Input impedance is 100
Ω , protected to ±6 V.
Front-panel LEMO connector.
CLIP Two front-panel LEMO connectors to provide
delay line clipping of the input pulse using an
external 50
Ω coaxial cable. Delay line clip is two
times the cable propagation delay. Gain is reduced
by a factor of two when using cable clip.
2.4. OUTPUT
OUTPUT Front-panel LEMO connector furnishes
the shaped and amplified signal through Zo<1
Ω ;
amplitude to ±5 V, rise time and decay time
controlled bythe Integrationand Differentiationtime
constant settings. Output is dc-coupled and
controlled by a continuous baseline restorer.
2.5. ELECTRICAL AND MECHANICAL
POWER The Model 863 does not have an internal
power supply and must obtain power from a NIM-
standard power supply such as the ORTEC
4001A/4002D NIM Bin/Power Supply.
POWER REQUIREMENTS +24 V, 83 mA; -24V,
83mA; +12 V, 167 mA;
! 12 V, 167 mA; +6 V,
320mA;
! 6 V, 320 mA.

3
WEIGHT
Net 1.5 kg (3.3 lb).
Shipping 3.1 kg (7.0 lb).
DIMENSIONS NIM-standard single-width module
3.43 × 22.13 cm (1.35 × 8.714 in.) per DOE/ER-
0457T.
3. INSTALLATION
The Model 863 contains no internal power supply
and must be powered from a NIM-standard bin and
power supply. The bin and power supply should be
turned off when modules are inserted or removed.
The power supply voltages should be checked after
modules are inserted. Ensure that the Model 863
has sufficient cooling air circulating to prevent any
localized heating of the circuitry. The Model 863
should not be subjected to temperatures greater
than 50
E C.
4. CIRCUIT DESCRIPTION
The Model 863 is composed of four separate timing
filteramplifiersconstructedonthesamePWB.Each
section is identical, and the circuit description that
follows relates to any of the four sections.
Component designations are the same for each
channel.
Each section of the 863 consists of a hybrid
differential amplifier, A1. The nominal gain of the
input section is 1×. The overall amplifier polarity is
selected by jumper W1 located on the PWB. See
Fig4.1foranillustrationof jumper selectionsettings
on the PWB. To access this and other jumpers,
remove the left side cover of the module. The 863 is
shipped with the polarity set as noninverting.
W1 Jumperselectionforinvert/noninvert
W2 and W3 Jumper selection for setting differ-
entiation(bothjumpersshouldbeset
identically)
W4 Jumper selection for setting inte-
gration
W5 Jumper selection for setting coarse
gain
Thedifferentiationcircuitfollowsthe input stageand
consists of a CR filter and a pole-zero cancellation
network. Both jumpers W2 and W3 should be set
when selecting the differentiation time constant.
Three differentiation time constant positions are
available: Out, 200 ns, and Optional. The 863 is
shipped with the W2 and W3 jumpers in the Out
position.TheOptionalselectionrequirestheaddition
of resistor R5 and capacitor C7. The following table
lists values of R5 and C7 corresponding to different
differentiation time constants.
Differentiation
Time Constant R5 C7
20 ns 499k 47 pF
50 ns 215k 150 pF
100 ns 100k 270 pF
200 ns 51k 470 pF
500 ns 21k 1200 pF
The Fine Gain stage is built around hybrid amplifier
A2 and is adjusted bythe front-panel potentiometer,
R11. The overall gain of this stage ranges nominally
from 0.2× to 5×, and is inverting.
The integration circuit follows the Fine Gain stage
and consists of an RC network. Jumper W4 selects
the integration time constant as Out, 50 ns, or
Optional. The 863 is shipped with the W4 jumper in
theOutposition.TheOptionalselection requiresthe
addition of capacitor C12. The following table lists
values of C12 corresponding to different integration
time constants.
Following the integration circuit is the Coarse Gain
stage built around hybrid amplifier A4. The Coarse
Gain can be selected as either nominally 1× or 5×

4
Fig. 4.1. Jumper Selection Settings.
Pin Function Pin Function
1 +3 V 23 Reserved
2 - 3 V 24 Reserved
3 Spare bus 25 Reserved
4 Reserved bus 26 Spare
5 Coaxial 27 Spare
6 Coaxial *28 +24 V
7 Coaxial *29 - 24 V
8 200 V dc 30 Spare bus
9 Spare 31 Spare
*10 +6 V 32 Spare
*11 - 6 V *33 117 V ac (hot)
12 Reserved bus *34 Power return ground
13 Spare 35 Reset (Scaler)
14 Spare 36 Gate
15 Reserved 37 Reset (Auxiliary)
*16 +12 V 38 Coaxial
*17 - 12 V 39 Coaxial
18 Spare bus 40 Coaxial
19 Reserved bus *41 117 V ac (neutral)
20 Spare *42 High-quality ground
21 Spare G Ground guide pin
22 Reserved
Pins marked (*) are installed and wired in ORTEC’s 4001A
and 4001C Modular System Bins.
Bin/Module Connector Pin Assignments For Standard
Nuclear Instrument Modules per DOE/ER-0457T.
using jumper W5, and is inverting. The 863 is
shipped with W5 in the 5× position.
The output driver stage is hybrid amplifier A5. This
amplifier can drive ±5 Vinto a50
Ω loadimpedance.
Overall dc-stability of the output level of the 863 is
provided by a continuous baseline restorer. The
operational amplifier, U1, is connected as an
integrator and feeds back the dc value of the output
voltage to amplifier A1. The nominal voltage gain of
the output driver stage is 10× noninverting.