HP 5304A Service manual

OPERATING AND SERVICEMANUAL
TIMER/COUNTER
5304A
w.0«
(iOtl
HEWLETT M PACKARD

CERTIFICATION
The Hewlett-Packard Company certifies that this instrument was
thoroughly tested and inspected and found to meet its published
specifications when it was shipped from the factory. The Hewlett-
Packard Company further certifies that its calibration measure-
ments are traceable to the U.S. National Bureau of Standards to
the extent allowed by the Bureau's calibration facility.
WARRANTY AND ASSISTANCE
ThisHewlett-Packardproduct is warrantedagainstdefects in
materials and workmanship.Thiswarrantyapplies forone year
from the date of delivery, or,inthe case of certainmajor com-
ponentslisted inthe manual, forthe specifiedperiod.
We willrepair or replaceproductswhichprove tobe defective
during the warrantyperiodprovidedthey are returned to Hewlett-
Packard. No otherwarranty is expressed or implied. Wearenot
liable for consequentialdamages.
Servicecontracts or customerassistanceagreements are available
for Hewlett-Packardproductsthatrequiremaintenance and repair
on-site.
Forany assistance,contactyournearestHewlett-PackardSales and
ServiceOffice.

III'M<>1 >EL5;MMATIMERcolINTER
Reeord of Revisions(ManualChangeI'ages)
REVISION
NUMBER DATE
ISSUED DATE
INSERTED INSERTED
BY

HI' MODEL:">;{( MATIMERCO IJNTK K
Record of Revisions(ManualChangePages)
REVISION
NUMBER DATE
ISSUED DATE
INSERTED INSERTED
BY
I

i
t
I
I
SECTION IXD
TIMER/COUNTER
5304A
SERIALPREFIX:1212A00467
Thissectionappliesdirectly toHP Modelf>H()lA,Timer
Countershavingserialprefixnumberl2P2A004ti7, and
must he insertedinto the 5300AMeasuringSystem M uiual.
NEWERINSTRUMENTS
ThisSectionwithenclosed"ManualChangesPages"
appliesdirectly toHP Model5.'U)4ATimerCountershaving
prefixnumbersabove1212A00467.
OLDERINSTRUMENTS
Changesre(|uired to back-datethisSection for olderinstru-
ments arcin Section IXI), Subsection VII.
CopyrightHEWLETT-PACKARDCOMPANY 1973
5301 STEVENSCREEKBLVD..SANTACLARA.CALIF.95050
Printed: AUG1973
HP PART NO. Jjjf
MANUAL05304-90006HEWLETT M, PACKARD

Model5304 A
Table of Contents
TABLE OF CONTENTS
Sectioni'age
IXI) 5304ATimer/Counter
Subsection
I GENERALINFORMATION91)1-1
91)-1-1.Introduction9D-1-1
91)-1-2.Description9D-1-1
91)-1-4.Purpose andUseof Section IXI) 91)-1-1
91)1-6.InstrumentIdentification91)1-1
91)1-8.ManualChanges and Options91)1-1
II INSTALLATION9D-2-1
9D-2-1.Unpacking and Inspection9D-2-1
9D-2-3.Storage and Shipment9D-2-1
9D-2-5.Installation and Removal of Plug-On9D-2-1
9D-2-8.PortableOperation9D-2-1
III OPERATION9D-3-1
9D-3-1.OperatingInformation 91)3-1
IV THEORY OF OPERATION9D-4-1
9D-4-1.Introduction9D-4-1
9D-4-4.InputAmplifiers9D-4-1
V MAINTENANCE9D-5-1
9D-5-1.Introduction9D-5-1
9D-5-3.RecommendedTestEquipment9D-5-1
9D-5-5.InstrumentAccess9D-5-1
9D-5-7.PeriodicMaintenance9D-5-1
9D-5-9.Maintenance and Repair9D-5-1
9D-5-13.InstrumentTroubleshooting9D-5-1
9D-5-16. DC BalanceAdjustment9D-5-3
VI REPLACEABLEPARTS9D-6-1
9D-6-1.Introduction9D-6-1
9I)-o-3.OrderingInformation9D-6-1
VII MANUALCHANGES AND OPTIONS9D-7-1
9D-7-1.ManualChanges9D-7-1
9D-7-3.NewerInstruments9D-7-1
9D-7-5.OlderInstruments9D-7-1
9D-7-7.Options9D-7-1
VIIICIRCUITDIAGRAMS 91)8-1
9D-8-1.General9D-8-1
ii

Model5304A
List of Figures
List of Tables
LIST OF FIGURES
FigurePage
91)1-1.5304ATimer/Counter9D-1-0
9D-3-1SignalConditioningUsingAttenuator,Level and
SlopeControls9D-3-1
9D-3-2.Front-PanelControls and Connectors9D-3-2
9D-3-3.Rear-PanelConnectors9D-3-4
9D-3-4.MakingSelf-CheckMeasurement9D-3-5
9D-3-5.MakingFrequency A Measurements9D-3-H
9D-3-6.MakingPeriodAverageMeasurements9D-3-7
9D-3-7.MakingTimeIntervalMeasurements9D-3-8
9D-3-8.Totalizing9D-3-10
9D-5-1.SeparationProcedure9D-5-2
9D-5-2.Frequency A TroubleshootingDiagram9D-5-5
9D-5-3.PeriodAverage A TroubleshootingDiagram9D-5-7
9D-5-4.TimeIntervalTroubleshootingDiagram9D-3-11
9D-5-5.Open/CloseTroubleshootingDiagram9D-5-13
9D-5-6.('heckTroubleshootingDiagram9D-5-I5
9D-8-1. Al TimeIntervalBoardAssembly,
A2 AttenuatorBoardAssembly9D-8-5
LIST OF TABLES
1 ablePage
9D-1-1.5304ATimer/CounterSpecifications9D-1-2
9D-5-1.In-CabinetPerformanceChecks9D-5-16
9D-6-1.ReplaceableParts9D-6-2
9D-6-2.ManufacturersCodeList9D-6-5
9D-8-1.InstrumentInterconnectionList9D-8-2
in

Model5304A
GeneralInformation
Figure91)-1-1.5304ATimer/Counter
FREQ A
:»::i:tw
^ XIOO ® PSET^»*»-
AUTO
ATTEN
xioo aioc^
w 5304ATIMER/COUNTEROPEN/CLOSE
A
9D-1-0

Model5.'{(MA
( ieneralInformatinn
SECTION IXD
5304ATIMER/COUNTER
SUBSECTION I
GENERALINFORMATION
9D-1-1.INTRODUCTION
9D-1-2.Description
9D-1-3. The Hewlett-PackardModel5304ATimer
Counter,whenpluggedonto anHP Model5300A
MeasuringSystem, is capable of: Measuring fre-
quencies upto10MHz, TimeIntervalmeasurements
from 500 nsec to 10,000seconds,PeriodAverage
over a range of10Hzto1MHz,and Totalizing.
The electrical and mechanicalspecifications are listed
in Table9D-1-1.
9D-1-4.Purpose andUseof Section IXD
9D-1-5.Section IXI) contains the documentation
necessary to operate,maintain, and repair theHP
Model5304ATimerCounterplug-on.Alsoincluded
are partslists,componentlocators, and schematics.
Thisinformation is intended tobe insertedinto the
5300AMeasuringSystemmanual as part of Section
IXof thatmanual.
9D-1-6.INSTRUMENTIDENTIFICATION
91)1-7. Hewlett-Packarduses a two-section,nine-
digitserialnumber(0000A00000)mounted onthe
rearpanel to identify the instrument. The first four
digits arethe serialprefix andthe lastfive digits
refer tothe specificinstrument. Ifthe serialprefix
on yourinstrumentdiffersfromthatlisted onthe
titlepage of thissection,there are differences
between the manual and yourinstrument.Iiower
serialprefixes are documented in Section IXI),
Subsection VIIand higherserialprefixes are covered
bya manualchangesheetincludedwith the manual.
9D-1-8.ManualChanges and Options
9D-1-9. The titlepagelists the serialprefixnumber
to whichthisinformationdirectlyapplies. Ifthe
serialprefix is differentfrom theone listed, a
changesheet is includeddescribing the required
changes. If thischangesheet is missing, the infor-
mation canbe supplied byany Hewlett-Packard
Sales and Serviceofficelisted in Section VIofthe
5300AMeasuringSystemManual.Options are listed
in Section IXI), Subsection VII.
9DII

Model5304A
GeneralInformation
Table91)1-1.5304 A Timer/CounterSpecifications
INPUTCHANNELS AANI)B
Range: DC coupled; 0to10MHz.
AC coupled; 100Hzto10MHz.
Sensitivity(min): 25mVrms sinewave
toIMHz.50mVrms sinewave to10
MHz.150mVp-p pulse at minimum
pulsewidth, 40 nsec.Sensitivity canbe
decreased by10or100 timesusing
ATTENUATORswitch.
Impedance: 1Mil shunted by lessthan 30pK
OverloadProtection: 250VrmsonXl()
and XI00attenuatorsettings. OnXI
attenuatorsetting 120Vrmsupto1kHz,
decreasing to10Vrmsat10MHz.
TriggerLevel:PRESETpositioncenters
triggeringabout 0 volts ±25mV,orcon-
tinuouslyvariableover the range of1Vto
+1V
timesattenuatorsettings.
Slope:Independentselection of triggering
on positive or negativeslope.
ChannelInputs:Common or separatelines.
GateOutput:Rearpanel BNC.TTLlow
levelwhilegate is open. Maybe used
to intensitymodulate anHP oscilloscope.
TIMEINTERVAL
Range: 500 nsec to10•sec.
Input:Channels AandB;canbe common
or separate
Overload:Maximumrecommendedlevels for
pulsesignals is2Vp-p. Clippingoccurs
at3Vp-p.
Resolution: 100 nsec to10msin decade
steps.
Accuracy: +1 count + timebaseaccuracy
+ triggererror.*
Display: fjs, ms,ors (seconds)withpositioned
decimalpoint.
TimeIntervalHoldoff:Frontpanel con-
centricknobwhichinsertsvariabledelay
of approximately 100 /jsec to100 msec be-
tweenSTART(Channel A)and enabling
STOP(Channel B);maybe disabled.Elec-
tricalinputsduringdelaytime are ignored.
Delay maybe digitallymeasured in CHECK
position.DelayOutput:rearpanel BNC.
TTLlow levelduringdelaytime. Maybe
used to intensitymodulate anHP
oscilloscope.
PERIODAVERAGE
Range: 10Hzto1MHz.
Input:Channel A.
PeriodAveraged: 1to10' automatically
selected for maximumresolution.
FrequencyCounted: 10MHz.
Accuracy:
+1
count + timebaseaccuracy
+ triggererror.**
Display: /JS,ms withpositioneddecimalpoint.
FREQUENCY
Range: 0to10MHz.
Input:Channel A.
GateTimes:Manuallyselected 0.1,1,or10
seconds.AUTOpositionselectsgatetime
to fill display for maximumresolutionwith-
ina 1-secondmeasurementtime.
Accuracy: +1 count + timebaseaccuracy.
Display: Hz,kHz,andMHz withpositioned
decimalpoint.
OPEN/CLOSE(Totalizing)
Range: 10MHz maximum.
Input:Channel A
Function:Inputsignaltotalizedwhilegate
open.Opening and closing of gateinitiated
by frontpanelpushbuttonswitch.
GENERAL
Check:Insertsinternal 10MHz reference
frequencyintoChannels AandB. Time
IntervalHoldoff maybe digitallymeasured
by switching to CHECK and TIME IN
TERVALpositions.
OperatingTemperature: 0°to 50°C.
PowerRequirements:Including5300A
mainframe,nominally 10 watts.Minimum
of3 hoursoperation(typically 5hrs)at20 C
to 30°Coperating and chargingtemperatures.
Weight: Net,1lb(0.9kg). Shipping, 314
lbs(1.5kg).
"Forany waveshape,triggererror is lessthan
±
0.005
SignalSlope (V/ps)/js
**Triggererror is lessthan ±0.3%ofone
period, i periodsaveraged for signalwith
40dBor bettersignal-to-noiseratio.
91)1-2

Model5304 A
Installation
SECTION IXD
5304ATIMER/COUNTER
SUBSECTION II
INSTALLATION
9D-2-1.UNPACKING AND INSPECTION
9D-2-2. Ifthe shippingcarton is damaged ask that
the carrier'sagent be presentwhen the instrument
is unpacked.Inspect the instruments for damage
such as scratches,dents,brokenknobs, etc.Ifthe
instrument is damaged or fails to meetperformance
testswhenusedwith the 5300AMeasuringSystem
notify the carrier andthe nearestHewlett-Packard
Sales and Serviceofficeimmediately.Performance
checkprocedures are located in Section IXD-5,
and Sales and Serviceoffices are listed in Section VI
ofthe 53(H)Aportion ofthe manual.Retain the
shippingcarton andthe paddingmaterial forthe
earner'sinspection. The Sales and Serviceoffice
willarrange forthe repair or replacement ofthe
instrumentwithoutwaiting forthe claimagainst
the carrier tobe settled.
9D-2-3.STORAGE AND SHIPMENT
9D-2-4.PACKAGING. To protectvaluableelectronic
equipmentduringstorage or shipmentalways use
the bestpackagingmethodsavailable.YourHewlett-
PackardSales and Serviceoffice can provide
packagingmaterialsuch as thatused for original
factorypackaging.Contractpackagingcompanies in
manycities can providedependablecustomer
packaging on shortnotice.Here isone recommended
packagingmethod:
a.The originalcontainer isa corrugatedcard-
board box with 200lbs. bursttest (HPNo. 9211-1620).
The instrument is secured and protected,while in
theboxbyatopand bottommoldedform of
polystyrenefoam (HPNo. 9220-1545).Alsoincluded
with the instrument isa plasticdust-protectioncover
HP Part No. 05300-80004.
9D-2-5.INSTALLATION ANI) REMOVAL
OF PLUG-ON
9I)-2-(>. The 5304ATimer/Countermust be usedwith
a mating5300AMeasuringSystembefore any
measurements canbe made. To mate the 5304A
Timer/Counterwith the 53(H)AMeasuringSystem, see
Figure 2-1and Paragraph 2-1ofthe 5300Aportion
ofthe manual.
9D-2-7.ENVIRONMENT.Conditionsduring
storage and shipmentshould be normallylimited
as follows:
a. Maximumaltitude:25,000feet
b. Minimumtemperature:-40°F ( 40°C).
c. Maximumtemperature:+167"F(+75°C).
9D-2-8.PORTABLEOPERATION
9D-2-9. TheuseoftheHP Model 531OA Battery
Packenables the 5300AMeasuringSystem and 5304 A
TimerCounter tobe used in areasremovedfrom ac
powersources. The531OA BatteryPackprovides a
minimum of3 hoursoperation(typically 5 hours) at
20°C to 30°Coperating and chargingtemperature.
Tables 1-2and1-4of 5300Aportion ofthe manual
list theHP 5310ABatteryPack asan available
accessory.Documentation onthe531OAis also
included in Section IV throughVIII olthe 5300A
portion ofthe manual. To prepare the 5300A5304A
for portableoperation,refer to Paragraph 2-15and
Figure 2-2, steps atocof 5300Aportion of manual.
9D-2-1

OPERATION
(
j

Model5304A
Operation
SECTION IXD
5304ATIMER/COUNTER
SUBSECTION III
OPERATION
9D-3-1.OPERATINGINFORMATION
9D-3-2. The 5300A/5304ATimer/Countermeasures
frequencies upto10MHz, periodaverage to1MHz,
timeintervalfrom 500 nsec to 10,000seconds; or
totalizesinputsignals.
Figure9D-3-1.SignalConditioningUsing
Attenuator,Level and SlopeControls
TRIGGER
VOLTAGE
NOTE ?
RECOVERY
VOLTAGE
+ SLOPE
0 LEVEL
PSET
HYSTERESIS
(NOTE I)
- SLOPE
I. HYSTERESIS(NOISEREJECTION) VO. TAGE IS CONSTANT FOR
EACHATTENUATORSETTING AND DOES NOT VARYWITH
TRIGGERLEVEL
2 THISALLOWSZEROVOLTSTRIGGERINGWITHGOODNOISE
REJECTION
3 ATTENUATOR: xi, xio.xiooCHANGESTRIGGERLEVEL AND
HYSTERESISVOLTAGES BY FACTORS OF I.IO.IOO
9D-3-3.There are fourbasicsignalconditioning
controlsused in Channel Aor Channel B(the effect
of thesecontrols is shown in Figure9D-3-1).
These are:
a. ATTENswitches for Channel AandB.
b. SLOPEswitches for Channel AandB.
c. LEVELcontrols for Channel AandB.
d. AC-DCswitches for Channel AandB.
9D-3-4.ATTEN. XI,X10, XI00switches(both
Channels.Largeamplitudesignals canbe attenuated
by using the ATTENswitches.Setting the attenuator
switchesincreases the triggerlevels andthe
hysteresisvoltages by factors of1,10,100.If input
signallevels are unknown, the initialmeasurements
should be madewith the attenuatorswitches set
to XI00. The attenuatorsettings are thenreduced
until a stable,useablemeasurement is obtained.
9D-3-5.SLOPESwitches(bothChannels). The
slopeswitchesallow the selection of triggering on
the positive (+)or negative (-) slope ofthe input
signals (see Figure9D-3-1).
9D-3-6.LEVELControls(bothChannels). The
levelcontrolsallowadjustment ofthe triggering
point onthe inputsignalwaveform.With the LEVEL
controls setto PSET or"0", triggering is centered
aboutzerovolts. The voltagerangeoverwhich
triggering maybesetis-1 volt to+1 volttimes
the ATTENswitchsettings (±1Vto+100V).
9D-3-7.AC-DCSwitches(bothChannels). The
AC-DCswitchesselect acordc coupling. InAC
position and PSET,triggering is centeredabout
ac-zero, anddc components onthe signalhave no
effect. InDC position and PSET,triggering is
centeredabout 0 volts dconthe signal.
9D-3-1

Model5304A
Operation
Figure9D-3-2.Front-PanelControls and Connectors
T.I.ATOB/ FREQ A
PEP,
10m«v AVO/A
\
XlOO
PUT AYTENLEVE
.1ms
00^DO
Kg] 5304ATII/ER/COUNTEROPEN.XCLOSE
A
1. COM-SEP-CHK.Threepositionswitch
enablesselection of inputsignalfrom
separate or commonsources or enables the
selection ofa Self-Checkposition.
a.COM: ConnectsINPUT Aand
INPUT Bin parallel.
b.SEP: Channel Aand Channel B
inputs are fromseparatesources.
c.CHK: Self-Checkverifiesthat
5300A 10MHz crystaloscillator and
countinglogic andthe 5304A
gatinglogic is functioning
correctly.
2. INPUT AandB. Inputsignalfrequencies
tobe measured are connected to INPUT
A. INPUT Bis used in timeinterval
measurements.
3. ATTEN.Three-positioninputsignal
attenuator for bothchannels.
a.XI: Connectsinputsignalsdirectly
to inputamplifiers.
b.X10: Attenuatesinputsignals by
factor of10.
c. XlOO:Attenuatesinputsignals
by factor of100.
9D-3-2

Model5304A
Operation
Figure9D-3-2.Front-PanelControls and Connectors(Continued)
4. AC-DC.Two-positionswitchallows
selection of ac-coupling or direct-coupling
to inputamplifiers.
5. SLOPE +,-. Selects the triggering on
positive or negativeslope ofthe input
signals.
6. LEVEL.Adjusts the inputtriggerlevels.
Preset to trigger at0 volts.
7. FUNCTION.Twelve-positionswitch
enables 4 modes of operations tobe
selected. The modes are:
a.T.I.AtoB: Enablestimeinterval
measurements tobe madefrom
500 nsec to 10,000seconds.
Resolution is adjustablefrom .1/JS
to10msinsix decadesteps.
b.PERAVGA: Enablesmultiple
periodaverages tobe madefrom 8.
Channel A withfrequencies of10
Hzto1MHz. Periodsaveraged
are automaticallyselectedfrom
1to10\
c. FREQ A: Enablesfrequency
measurementsfrom 0to10MHz
when dc coupled and100Hzto
10MHz when ac coupled.
1) AUTO:Gatetime is auto-
maticallyselected to fill thedis-
play for maximumresolution of
the signalbeingmeasured,without
overflow, uptoa maximum, of
1 second.
2).IS,IS,10S: Countergatetime
is manuallyselected for.1 seconu,
1 second or10 seconds.
d. OPEN/CLOSE A (Totalize): En-
ablesinputsignals to Channel Ato
be totalized.Totalizing is initiated
by pressingOPEN/CLOSE A switch
and terminated by pressing the
switch a secondtime.
DELAY.Adjustmentinserts a timeinterval
delay of100 /jsec to100 msecbetween
Start(Channel A) signal and Stop(Chan-
nelB) signal;whendisabled,there isa
residualdelay of about4200nsec.
9D-3-3

Model5304A
Operation
Figure9D-3-3Rear-PanelConnectors
GATE OUT
DELAY OUT
1. GATE OUT:A TTL-LOWlevelsignal
while the 5300Amaingate is open.
2. DELAY OUT:A TTL-LOWlevelsignal
during the delaytimeselected by front-
panelDELAYcontrol (inT.I.AtoB
modeonly).

Model5304A
Operation
Figure9D-3-4.MakingSelf-CheckMeasurements
NVCLOSE
l(REAR)
/
INPUT
XIO
xioo I
ATTEN
XI
XIO
XiOC »DC
mi 5304ATIMER/COUNTER
PSE
SLOPELEVEL
0
PSET**
IATOB FREQ A
PER
10ms
Ims
.1ms
10ps
IMS
lus
1 Connect ac power to 5300A ac receptacle.
2. Turn ac power "on" with5300ASAMPLE
KATEcontrol.AdjustSAMPLEKATE
for desireddisplaytime.
3.Set 5304A COM SEP-CHKswitch toCHK.
4.Set 5304A"Function"switch to FREQ A,
AUTO.Displayshould he 10.0000 MHz,
+1 count.
5.The timeintervalhold-off maybe meas-
ured by selecting onoftheT.I.AtoB
positions ofthe "Function"switch.
9D-3-5

Model5304A
Operation
Figure9D-3-5.MakingFrequency A Measurements
XIOO
IMER/
I (REAR)
/
INPUT ATTEN
T.I.ATOB
PER
10msvAVG'
\•
tms—^
.1ms
10|iS
Ips
MS—
OPEN
FREQ A
AUTO
It
Is
108
OSEA
PSET^
SLOPE LEVEL
Q +
1. Connect ac power to 5300A ac receptacle.
2. Turn ac power "on" with5300ASAMPLE
KATEcontrol and adjustsamplerate for
desireddisplaytime.
3.Set COM-SEP-CHK toSEP.
4. Connectinputsignal to INPUT A jack.
5.Set ATTEN to XI00;AC-DC U> coupling
desired and SLOPE to polaritvdesired.
Set LEVEL to PSET.
(>.Set "Function" to FREQ A, AUTO and
adjust the ATTENswitchuntil a stable
display is obtained. The gatetime may
be adjusted for.Is,Is,or10sec.

Model5304A
Operation
FREQ A
NPUT
xioo mDC•
53/4ATIMER/COUN/
Figure9D-3-6.MakingPeriodAverageMeasurements
I (REAR)
1. Connect tic power to 5300A ac receptacle.
2. Turn ac power "on" with5300ASAMPLE
KATEcontrol.Adjustsamplerate for
desireddisplaytime.
3.Set COM-SEP-CHK toSEP.
4. Connectinputsignal to INPUT A jack.
5.SetAITENto XI00,AC-DC to coupling
desired and SLOPE to polaritydesired.
Set LEVEL to PSET.
().Set "Function" toPERAVGA; adjust
A'lTENswitchuntil a stabledisplay is
obtained. The number of periodsaveraged
is automaticallyselected.
9D-3-7

Model5304 \
Operation
l(REAR)
AUTO
Figure9D-3-7.MakingTimeIntervalMeasurements
1. Connect ac power to 5300A ac receptacle. 6.
2. Turn ac power "on" with5300ASAMPLE
RATEcontrol.Adjustsamplerate for
desireddisplaytime.
3.Set "Function"switch toT.I.AtoB,
withdesiredresolution.EnsureDELAY
control is full ccw.
4.Set ATTENswitches for bothchannels to
XI00;AC-DCswitches and SLOPEcontrols
switches to settingsdesired; set LEVEL
controls to PSET.
5.If Start and Stopsignals are fromseparate
sources,connect the Startsignal to INPUT
A connector andthe Stopsignal to INPUT
B connector,then setthe COM-SEP-CHK
switch toSEP.Ifthe Start and Stop
signals are from a commonsource,connect
the signalinput to INPUT Aandsetthe
COM-SEP-CHKswitch toCOM.
AdjustATTENswitchesuntil a stable dis-
play is obtained.
TimeIntervalHoldoff(DELAY). The
I)p]LAYcontrolinserts a delay of about
100 psec to100 msecbetween the triggering
ofthe STARTChannel "A"andtheen-
abling ofthe STOPChannel "B"(see
Figure B). Thisdelay maybe used to
measurerelay or othermechanical
switchtimingsequenceswithouterror
dueto contactbounce. Itmay also be
used for measurements on pulsetrains;
for examplefrom the startpulse toa later
pulse, inthe presence of interveningpulses.
Tousethe DELAY,proceed as follows:
a.Ifthe desireddelay is known, it
maybesetand measured by
selecting T.I.AtoBandCHKand
settingDELAYcontrol tothe desired
delaytime. The measurement may
then be made by switching COM-
SEP-CHK in step 5.
9D-3-8