Precision 283 User manual

DYNASCAN CORPORATION
1801WestBellePlaineAvenue,Chicago, Illinois 60613
INSTRUCTION
MANUAL If^PRECISION
283
Hi Ml
31/2-DiGiT
DIGITALMULTIMETER
IfCPRECISION
Productof DYNASCANCORPORATION
1801WestBellePlaineAvenue,Chicago,Illinois 60613
STEAM POWERED RADIO.COM

INSTRUCTION MANUAL
FOR
Model 283
31^-DIGIT
DIGITAL MULTIMETER
DYNASCAN CORPORAT/ON
1801WestBellePlaineAvenue
Chicago, Illinois 60613
STEAM POWERED RADIO.COM

TABLE OF CONTENTS
PAGE
INTRODUCTION 3
SPECIFICATIONS 4
CONTROLS AND FEATURES9
OPERATION
PreparationandCheck11
Interpretation of Digital DisplayReadings12
DC VoltageMeasurements13
AC VoltageMeasurements13
Resistance Measurements
Out-of-Circuit 14
In-Circuit 14
Out-of-Circuit Semiconductor Tests 14
DC CurrentMeasurements15
AC CurrentMeasurements16
BATTERY PACK BP-83ACCESSORY17
1 OOV and234V LINE OPERATION 19
THEORY OF OPERATION 20
Block Diagram21
CALIBRATION PROCEDURE22
FUSE REPLACEMENT 23
WARRANTY SERVICE INSTRUCTIONS 24
ONE YEAR LIMITED WARRANTY Cov.3
INTRODUCTION
TheB & K-Precision Model 283 Digital Multimeter isa significantcontribution
to theinstrumentationmarket.Lowcostand high performance have been
engineeredintothisinstrumenttomakeavailabletotheengineer,technician,
maintenanceandservicepersonnel,andtraininginstitutionsa digital multimeter
thatiscompetitivelypriced with existinganalog meters and which, atthe same
time, exceeds theperformanceof these meters.Inaddition,the basic instrument
has been designedformaximum simplicity ofoperationand minimum errorof
reading.
The basic designfeaturesofthisinstrumentmakeitanidealreplacementfor
existing multimetersand FET/VOM's. Theinstrument measures DCandAC
voltage, currentandohms.Ithas high inputimpedance(10megohms)onallvoltage
ranges, anda wide resistance measurement range (100ohms full range to10
megohms full range), with 100%overrange.Inadditionto providing equivalent
functions and ranges, theinherentaccuracyofthisinstrumentprovidesasignificant
margin of improved performanceoveranalogmultimeters.
A selectable High/Low Ohmsfeature,generallynotavailableon digital
multimeters, permitsmaking in-circuit resistance measurements atvoltagelevels
below theconductionthresholdofsemiconductors.
Theoverloadprotectionsystemwasdesignedtoprovidemaximumprotection
of theinstrument with minimum user inconvenience,intheeventofextreme
overload accidents.
A batterypackoptionisavailable which makes the Model 283completely
portableandisolated.Thepackmountsinsidethe meter's case, requiring only a
screwdriver for installation. Thisoptionprovidesmorethan8 hours'continuoususe
beforeanovernightrechargeis needed and unlimited use while pluggedintoanAC
line.
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SPECIFICATIONS
DC VOLTAGE
Ranges
Overrange
Maximum DCInput
Accuracy
Input Impedance
Polarity Indication
OverrangeIndication
Circuit Protection,
All Voltage Ranges
±0-1.000, 10.00,100.0, lOOOV.
100percentto ±1.999, 19.99,199.9,1500V.
1500voltsDC,orDC+ AC peak.
±.5 percentofreading,±1 digit, 1,10, lOOV range.
±1.0 percentofreading,±1 digit, lOOOV range.
10megohms.
Automatic; minussignshown,plussign implied.
If theinputvoltage exceeds 200percentof full range,
thetopandbottom segments onthe first digit will
flash while thedisplay reads "000"(= •••). The
polarity ofoverrangeisindicated.
±1500 VDC or1500 VDC + AC peak.
AC VOLTAGE
(Averagereading circuitry calibratedtoreadRMSvalueofpuresinewave.)
Ranges
Overrange
Maximum ACInput
Accuracy
0-1.000,10.00,100.0, lOOOV RMS.
100percent,to 1.999, 19.99,199.9, lOOOV RMS.
lOOOV RMSor1500V peak.
±1 percentofreading,±1 digit, 1,10, lOOV ranges.
±1.5 percentofreading,±1 digit, 1000Vrange.
4
Frequency Response
Input Impedance
±1 percentaccuracy:40Hzto400Hzon1,10and
lOOV range.
±1.5 percentaccuracy:40Hzto400Hzon lOOOV
range.
10megohms.
OverrangeIndication
Circuit Protection,
All Voltage Ranges
If theinputvoltage exceeds 200percentof full range,
thetopandbottom segments ofthe first digit will
flash while thedisplay reads "000"{- •••).
lOOOV RMSor1500 VDC + AC peak.
DC CURRENT
Ranges
Voltage Drop(Measured
atInstrumentTerminals)
Overrange
Accuracy
Polarity Indication
OverrangeIndication
Circuit Protection,
All Ranges
O-I.OOO, 10.00,100.0,1000mA.
250mV (650mVon1000mArange)maximum.
100percent,to1.999,19.99,199.9and1999mA.
±1 percentofreading,±1 digit, 1,10,and100mA
range.
±1.5 percentofreading, ±1 digit, 1000mArange.
If a DCcurrentofnegativepolarityisappliedtothe
input, theminussign will light. Theplussignis
implied.
If theinputcurrent exceeds 200percentof full range,
thetopandbottomsigmentsofthe first digit will
flash whUethedisplay reads "000"(= •••). The
polarity ofoverrangeisindicated.
Fuse anddiodes. Fuse externally accessible at front
panel.
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AC CURRENT
Ranges 0-1.000,10.00,100.0,1000mA.
Voltage Drop(Measured
atInstrumentTerminals)250mVRMS(650mVRMSon1000mArange)
maximum.
Overrange
Accuracy
Frequency Response
Overrange Indication
100percent,to 1.999, 19.99,199.9and1999mA.
±1.5 percentofreading,±1 digit, 1,10and100mA
range.
±2 percentofreading, ±1 digit, 1000mArange.
40Hzto400Hzatstatedaccuracy.
If theinputcurrent exceeds 200percentof full range,
thetopandbottom segments ofthe first digit will
flash while thedisplay reads "000"(= •••).
Circuit Protection,
All Ranges
Fuse anddiodes. Fuse externallyaccessibleat front
panel.
RESISTANCE
Ranges 0-lOO.Oohms;1.000,10.00,100.0,1000kohms;10.00
megohms.
Overrange100percent,to199.9ohms; 1.999, 19.99,199.9,
1999k ohms;19.99megohms.
Accuracy ±1percentofreading,±1 digit, Ikohmto1000k
ohm ranges, in HIGH ohms function.
±2 percentofreading,±1 digit, 10megohmsrange,
HIGH ohms function and100ohmto1000kohmrange,
LOW ohms function.
Maximum TestCurrents100f21mA
lkS2 1mA
lOkfi lOOpA
lOOkO lOqA
lOOOkO 1/rA
10Mf2 lOOnA
6
Polarity
VOLTS/OHMS (red)jackispositiveforall ranges.
Maximum Open
Circuit Voltage
Voltage with Full
ScaleReading
Circuit Protection,
All Ranges
GENERAL
Operating Temperature
StatedAccuracy
MeasuredAt
TemperatureCoefficients
PowerSource
PowerConsumption
Line Cord
Sampling Rate
Settling Time, All
Ranges & Functions
8 volts.
0.2 volt in LOW ohms.
2 voltsin HIGH ohms.
-500V to+1000 VDC + AC peak,continuous.
Will withstandmomentaryoverloadsto ±1000 VDC
+ ACpeak with nocomponent failure.
15°Cto35°C.
25°C±1°C.
±0.025%/°C onDC Volts.
±0.05%/°C allotherfunctions.
117VAC50/60Hzfactory wired (usermay change
to lOOV or234Vby moving internaltransformer
tap).
7wattsmax.;12wattsmax.ifalsochargingbattery.
3-wire, detachable.
3readingspersecond.
Lessthanonesecond.
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AccessoriesIncluded
Optional
Dimensions
Weight
Two test leads.
BP-83 Rechargeable Battery Pack.
PR-21Isolation/Direct Probe (aidsDC measurements
in presence ofRF).
PR-23 RFDetector/DemodulatorProbe,15kHzto
250 MHz.
PR-28High-VoltageProbe.
LC-83 Carrying Case.
3-5/8" X 7" X 9",excludinghandleand tilt stand.
6lbs.
8
CONTROLS AND FEATURES
(See Fig. 1)
FUNCTION SWITCH. Selects thetypeof measurement tobeperformed.Also used
to turntheinstrumentONandOFF.
ZERO ADJUSTMENT. Usedtozerothedisplay with the test leads shortedonany
range orfunction. Precise zeroindicatedbyflashingminus(-)signinDCVorDCA.
RANGE SWITCH. Selects thedesired range forthe measurement selectedbythe
FUNCTION switch.
POSITIVE (VOLTS/OHMS) TEST LEAD JACK. "Hot"inputjack.Involtage
measurements the test leadconnectedtothisjackisnormallyappliedtothe
potential pointinthe circuit mostremoved from signalgroundorearthground.
NEGATIVE TEST LEAD JACK. Commonconnectiontotheinstrumentinput;it
shouldbeconnectedtogroundora lowimpedancepointwhenmeasuringvoltage.
Thejackdoublesasthe 2A-3AG fuseholder.
CURRENT (mA) TEST LEAD JACK. Thisjackis used whenmeasuringDCandAC
currents.
MINUS SIGN. A minus(-)indication will bedisplayedonDC Volts orDCCurrent
for a negativevoltageorcurrentrespectively. NOTE: Thepositive(+)signis
implied andisnotdisplayed.
NUMERICAL READOUTS. 314-digitdisplay.Firstdisplayindicatesminussignand
1; last three displaysindicatenumerals from "0"to"9".
HANDLE. Forcarryingtheinstrument.
TILT STAND. Canbe used to raise front ofthe283forconvenient viewing angle.
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10
OPERATION
PREPARATION AND CHECK
a.Hugthered test leadintothe VOLTS/OHMS jack,andtheblack test lead
into theblackjack.
b. Turn unit onbysettingthe FUNCTION switchto HIGH S2andthe
RANGE switchto lOkJl.
c. Without a resistance connected across the test leads,theoverrange
indicating shouldoccur,andshortingthe test leads shouldproducea zero
reading.CheckZEROadjustment.
d. Return FUNCTION switchtoACVorDCVand RANGE switchto
lOOOV. Itisgoodpracticetoleavetheinstrumentinthispositionwhen
not inusetopreventaccidentaloverloads.
SAFETY PRECAUTIONS
A certainamountof danger isalways present when working on
electrical equipment,andtherefore,the user iscautionedtoalways
familiarize himself asmuchaspossible with theequipmenttobetested,
beforeany work isperformed.Itshouldbekeptin mind that high
voltagesoften appear atunexpectedpointsindefectiveequipment.
When testing high voltagecircuits,developthehabitofkeepingone
handinyourpockettominimizethehazardofaccidentalshock.Itis
alsoimportantto have a properlyinsulated floor or floor coveringto
standon while taking measurements. Beparticularlycarefultoavoid
contact with nearbyobjects which couldprovidea groundreturnpath.
It isgoodpracticetoremove operating power beforeconnecting
test leads.Anisolationtransformeralwaysshouldbeusedinequipment
having the chassis tied toonesideoftheACpower line.
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Table1
INTERPRETATION OF DIGITAL DISPLAYREADINGS
SET SET
DISPLAY
TO FUNCTION
RANGE
FULL
READINGS
RESOLU-
MEASURE SWITCH SWITCH
SCALE
AREIN:
TION t
DCVOLTS
0-2V
DCV IV
1.999
Volts ImV
0-20V
lOV
19.99
Volts lOmV
0-200V
lOOV
199.9
Volts O.IV
0-1500V
lOOOV
1500*
Volts l.OV
AC VOLTS
0-2V
ACV IV 1
999 Volts ImV
X ill V
0-20V
lOV
19.99 Volts lOmV
0-200V lOOV
199.9 Volts O.IV
0-lOOOV lOOOV
1000**
Volts l.OV
CURRENT
0-2m A
DCA 1mA m
A 11I A
0-20mA 10mA 19.99
mA
lOqA
0-200mA 100mA 199.9
mA 100/zA
0-2Amp 1000mA 1999
mA 1mA
AC
CURRENT
0-2mA
ACA 1mA
1.999
mA liiA
0-20mA 10mA 19.99
mA
lOjuA
0-200mA 100mA 199.9
mA
lOOqA
0-2Amp 1000mA 1999
mA 1mA
OHMS
0-200f2 OHMS
100S2
199.9
Ohms
o.m
0-2000f2
(HIGH or LOW)
ikn 1.999
Kilohms
0-20kf2
10kf2
19.99
Kilohms ion
0-200kn 100kf2
199.9
Kilohms loon
0-2Mn
lOOOkfl
1999
Kilohms
ikn
0-20Mf2
lOMfi
19.99
Megohms
lokn
NOTES
*Donot exceed input levels of1500VDCorDC+ AC peak.
**Donot exceed input levels of1000VRMSor1500V peak.
12
t Resolution indicates the change inthe measured value that isrequiredtoshiftthe
least significant(right hand) digit,one count.
TABLE 1 isprovidedasanaidtooperationoftheModel283and,inaddition,
provides interpretationofthe displays obtained.Note that thedecimallocation
changes with thepositionoftheRANGEswitch.Thesignificanceofthedecimal
location must beknownto assure proper interpretationofthe readings obtained.
2.DC VOLTAGE MEASUREMENTS
a.SetFUNCTIONswitchtotheDCVposition.
b. Short the test leads and zero theinstrumentbyturningtheZEROcontrol
until theMINUSsignjustlightsorflickers with a zero reading displayed.
c.SetRANGEswitchasrequiredforthevoltageamplitudetobe measured.
If the magnitude ofthevoltageisnotknown,settheRANGEswitchto
thelOOOVpositionand reduce the settings asrequiredtoobtaina
satisfactory reading.
d.Ifthevoltage exceeds that ofthe range selected, the overrange indication
will operate andflash. Select a highervoltage range.
3.AC VOLTAGE MEASUREMENTS
a. Place theFUNCTIONswitchintheACVposition.
b. SettheRANGEswitchtothe desired voltage range. Ifthevoltage exceeds
that ofthe range selected, the overrange indication will operate andflash.
Select a highervoltage range.
4. RESISTANCEMEASUREMENTS
CAUTION
Donot attempt to measure resistance ina circuitinwhichthe
powerapplied. Remove thepowerand make sure that all capacitors
are discharged before attemptingin-circuit resistance measurements.
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OUT-OF-CIRCUIT:
(1) Setthe FUNCTION switch tothe HIGH f2position.
(2) Setthe RANGE switchtothedesiredposition.
(3) Ifthe resistance valuebeingmeasured exceeds thevalueofthe range
selected,theoverrange circuitry isenergizedand will flash.Selecta
higherrange.
IN-CIRCUIT:
(1) The Model 283hasselectableLOWand HIGH ohms ranges.
Conventional resistance measurements canbeperformedonall ranges.
TheLOWohmspositions limit themaximum test voltagedeveloped
across themeasured resistance to0.2 volt with a full scale reading.
This lowvoltagepermits accurate measurements of in-circuit re-
sistances shuntedbysemiconductorjunctions.
Theapplied test voltageisproportionaltothe resistance reading
observed,varying from zero with the test leads shortedto.2 volt fora
full scale reading.Forexample,inthe100f2 range with a resistance
readingof50.0ohms,thevoltagedeveloped across the resistance
under test is.05 volt.
When usingthe HIGH ohmspositions,a full-scalevoltageof2 voltsis
developed across themeasured resistance. Again, thevoltagede-
veloped across themeasured resistance isproportionaltothe
resistance readingobserved.Reversingthe leads will resultinthe same
reading (within 1%)ifthereisnoshuntingbya semiconductor,andis
agoodquickcheckthattheaccuracyofthemeasurementisnotbeing
affected bysemiconductors.
OUT-OF-CIRCUIT SEMICONDUCTOR TESTS:
In additiontoconventional resistance measurements, the HIGH ohms
ranges canbeusedto verify thata semiconductor junction isgoodby
checking thefront-to-backratio.
(1) SelecttheIkf2range.
(2) Removedevice from circuit.
(3) Connectthe test leads tothedevice(e.g.:diode,base-emitteror
base-coUectorjunction)andthen reverse theleadconnections.
Observethemeterreadingforbothconditions.
14
TEST RESULT
CONDITION
(a)Overrange,bothpolarities
Junction Open
(b) ZeroorLowReading,both
polarities
Junction Shorted
(c) Overrangeinonedirectionand
In-RangeReadingintheother
Junction Probably
Good
(4) Thein-rangereadingof Step (c)canbeusedtodeterminewhetherthe
deviceunder test is silicon orgermanium.A readingof400to700
indicatesthedeviceis silicon. Anindicationof100to300indicates
thedeviceisgermanium.
(5) The "I-V" curveofthedevicemaybedrawnusingthe accurate
current sources ofthe283. With the FUNCTION switchsetto
HIGH S2, notethereadingfor each positionofthe RANGE switch,
lkf2 through lOMfl. Disregardingthedecimalpointlocation, each
readingisnumericallythevoltageinmV across thedevice junction
with thecurrentthroughitlistedas Maximum TestCurrentin
specificationssection.
DC CURRENT MEASUREMENTS
a. Place the FUNCTION switchintheDCAposition.
b. Place the RANGE switchinthedesiredcurrent range position.Alwaysset
the RANGE switchtothe1000mApositionifthemagnitudeofcurrentto
bemeasuredisnotknown.
c.Connecttheplus(+) test leadtothecurrent ("mA") test leadjack.
CAUTION
Use care inmakingcurrent measurements. Make
sure thatthemeterisconnected in-series with the
loadsin which thecurrentistobemeasured.Never
connectthemeter across a voltage source with the
FUNCTION switchsetforcurrent. Doing somay
either blow theoverloadprotectionfuseor damage
theequipmentunder test.
When connectingthemultimetertoreadcurrent, first removepowerto
the circuit. The following rules will insurethatthepropercurrentpolarity
is indicated.
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(1) Wheninsertingthemultimeterbetweenthepositivesideofthepower
source andtheload,connectthepositiveleadtothepower source and
thenegativeleadtotheload.
(2) Wheninsertingthemultimeterbetweenthenegativesideofpower
source andtheload,connectthenegativeleadtothepower source
andthepositiveleadtotheload.
d. Apply powerandreadcurrent.
e.Ifthepolarityofthecurrentbeing measured isnegative,thepolarity
sensing circuit will beenergized,andthevaluedisplayed will bepreceded
by a minus(-)sign.
f. Ifthemagnitudeofthecurrentbeing measured exceeds thatindicatedon
the RANGE switch,theoverrange circuitry will operate. Whenthisoccurs,
immediately removepower from the circuit under test and select a higher
current range beforeproceedingfurther.
NOTE
Current ranges arefuseprotected.Ifinoperative,refertoFUSE
REPLACEMENT section.
AC CURRENT MEASUREMENTS
a.Setthe FUNCTION switchtothe ACA position.
b. Setthe RANGE switchtothedesiredposition.Ifindoubtaboutthe
magnitudeofthe.currenttobe measured, usethehighestcurrent range
andthenadjustthe RANGE switchasrequiredtoobtaina satisfactory
reading.
c.Connecttheplus(+) test leadtothecurrent ("mA") test leadjack.
d. Whenconnectingthemultimeterforcurrent measurements removethe
power from the circuit being tested while theconnectionsarebeing made.
Reapplythepowerandreadcurrent.
e.Ifthemagnitudeofthecurrentbeing measured exceeds the range selected,
theoverrange circuitry will operate. Whenthisoccurs,immediatelyremove
power from the circuit under test and select a highercurrent range before
proceedingfurther.
NOTE
Current ranges arefuse-protected.Ifinoperative,refertoFUSE
REPLACEMENT section.
16
BATTERY PACK BP-83 ACCESSORY
INSTALLATION (Referto Fig. 2)
1. With theModel283unplugged,removethetwo screws onthebackthatfasten
thecover. Lift the rear ofthecover, slightly andslideitforwardto expose the
insideoftheinstrument.
2. Thereisa pairofblackplasticconnectors near thetransformer which join the
transformerwirestothemain circuit board.Carefully pull theconnectors
apart, holdingthembytheshells,notbythewires.
3. Place theBP-83assemblyinthe space near thetransformer, with thebattery
againstthe rear ofthe chassis. Locatethebatterysothattheterminalpolarity
isasshowninFig.2.Slidetheassemblyback,sothatthehookedtabofthe
bracket fits throughtheslotatthe rear ofthe chassis andpushitdown.
4. Insertthetwo screws suppliedthroughthebottomofthe chassis intothe
BP-83bracketandtightenthemsnugly.
Fig. 2.Internalview.
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5.Connectthetwoplasticconnectorsof step 2 tothecorrespondingconnectors
of theBP-83(theyonlyfitoneway- donotforce).
6.CheckpolaritystampedonbatteryagainstFig.2,thenconnecttheshortred
(+) andblack(-)wirestothebatteryterminals. Replace cover.
OPERATION
WhenevertheinstrumentispluggedintoanACoutlet,thebatteryisbeing
charged.Thecharging rate varies with thebattery's state of charge toprevent
overcharging.Whenoperatingaway from ACpower,theunitmaybe used
continuouslyformorethaneighthoursbeforethedisplaydimsandanovernight
recharge is needed. Themetercanbe used while recharging,althoughthislengthens
the charge timerequired.
18
lOOV and234V LINE OPERATION
(RefertoFig.2)
TheModel283isfactory-connectedforuse with 117V,50/60HzAClines.To
operate iton lOOV or234V50/60Hzpower,aninternalconnectionmustbe
moved, as follows:
With theunitunplugged,removethetwo screws onthebackthatfastenthe
cover, lift the rear ofthecover slightly andslideitforwardto expose theinside
of theinstrument.Locatethetransformerand lift thewhitewireoffits center
"quick-disconnect"terminal.Thismustbemovedtooneofthetwoother
terminalsasshowninFig.2.
If theunitistoberunon234Vpower,thelinefuseshouldbechanged.
Notethemannerin which the original 1/8Aslow-blowfuseissolderedto
terminal stripon rear, thenremoveit. Replace with 1/16A-250Vslow-blowfuse
supplied.Thewires within the detachable linecordarecolor-codedaccordingto
theEuropean DIN standard.
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THEORY OFOPERATION
(Referto Block Diagram,Fig.3)
TheModel283 operates byconvertingthevarioustypesofinputsignalsintoa
scaledDCvoltage which isthentransformedinto digital informationbythe
integratorandlogiccircuits.
Voltage inputsareappliedthroughtheattenuator(resistornetworkRNl)toa
high impedancevoltage follower (ICl)fora 2 volt full scale swing.ACvoltagesare
thenfull-waverectified, filtered, andscaledtoproducea DCvoltageequaltothe
RMS valueofa sinewave.
Resistance measurements are made bygeneratinga precisionconstantcurrent
(controlled by1C4) which developsa DCvoltage across the measured resistor
proportional toits resistance. Thesignalisthenappliedtothe follower and
processed asforvoltage measurements with theexceptionthat,when LOW f2is
selected,thecurrent source isdividedby10andthegainofthevoltage follower is
switched from xltoxlO,toprovidea full scale swing from 0.2voltsatitsinput.
The RANGE switchpicksthemagnitudeofthecurrent generated (1mAmax.).
Forcurrent measurements, theinputis passed throughoneoffoursmallshunt
resistances todevelop0.2voltsfora full scale reading.Thisvoltageisappliedtothe
voltage follower initsgainof10mode.
Theoutputofthevoltage follower (orofthe AC-to-DC converter)isconverted
to digital formatbythedual-slopeintegrator(1C2C)andthe L.S.I, logicchip(1C6).
The2 references used fortheintegrationarederived from a highly stable zener
(Dl 1) with fixed currentdrive.
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MODEL 283 CALIBRATIONPROCEDURE
(Referto Fig. 2 forLocationofInternalAdjustments)
Theinstrumentshouldnotrequirecalibration unless repairs have been made
that change thefactorycalibration.Priortocalibration,theinstrumentshouldbe
checkedforproperoperationofallfunctionsandfor damage from physical abuse
orunprotectedoverloads.
The following procedureshouldbeperformed with lowimpedanceconstant
voltage sources of0.1%accuracyorbetter.Useof sources with less accuracy
reduces theaccuracyoftheinstrument.
Thecalibrationisperformed with thetopcoverremoved.Toremovethetop
cover from theunit,thetwo screws holdingthecovermustberemoved.Then lift
thebackofthecoverup slightly andforwardtoclearthe tabs onthe front panel.
EQUIPMENT REQUIRED.
DCV meter, 0.1 mVresolution.
1.5V ±0.1% voltagesource.
1.5kS2 ±0.1% resistor.
PROCEDURE (These steps mustbeperformedinorderlisted):
1. Cormectvoltmeterbetweenthewire"T.P."andcommoninputjack.
2. Setunitto DCV, IVrange, with inputsshorted.
3.Adjust front panelZEROfora measurement of0 ±0.1mV atT.P.Disconnect
voltmeter from unit.
4. Adjust A/D trimpotfordisplayof.000 with minussignflashing.
5.Removeshort from inputandapply+1.500VDC;adjust+Vpotforthis
reading.
6. Apply -1.500 VDC; adjust-Vpotforthisreading.
7.Removevoltage source andshorttheinputs.
8.Set FUNCTION toACV.RotateACpotclockwise until a displayof 1 or2mV
isobserved,thenbackoffcounterclockwisejustenoughtoachievea steady
zero.
22
9.Set FUNCTION to HIGH f2andconnectreferenceresistortoinputs.Adjust J2
potforcorrectreading.
10. Closecover.
FUSEREPLACEMENT
Thenegativejackis also a fuseholder.Toreplacefuse,pushinandturnthe
insertcounterclockwisetoremovethefuse.Replace only with the proper 2A-3AG
type fuse. To re-assemble, insertnewfuse,pushinandturntheinsertclockwiseto
theinternalstop.
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i 1 ! i 1 1 T ' f 1 T i 1 1 f i T 1 f r
DS-3 DS-4
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B & K-PRECISION MODEL 283 PARTS LIST
488-16309-002-B
SCHEMATIC B & K
SYMBOL DESCRIPTION PART NUMBER
RESISTORS
R25 0.098n,'AW, Vi% Wirewound 004-125-9-001
R260.9f2, lW,iA% Wire wound 004-160-9-001
R279S2, >AW, 'A%Metal Film Oil-088-9-001
R289012, 'AW, 'A% Metal Film 011-089-9-001
R34 470kl2,'AW, 5%MetalFilm 011-102-8474
R46100kS2,5W,10% Metal Glaze004-161-9-001
R47Special, High VoltageCurrent Limiter, 004-163-9-001
Base Resistance, 2kl2 ±40%
R492.5kl2 Trimpot 008-236-9-001
R52100kl2 Trimpot 008-238-9-001
R53,54, 5550012 Trimpot 008-237-9-001
R568.87kl2, 'AW, 1%, Metal Film 011-122-9-001
R218100kl2 Multi-turn Potentiometer008-254-9-001
CAPACITORS
CI, 2,20lOOpF,500V,10%Pre-formedCeramicDisc020-044-9-001
^^j^^^ } -^^f^^' 100V,-20,+80%Pre-formedCeramic Disc. 020-101-9-001
C9.OOl/uF, IkV, 10%Pre-formedCeramicDisc020-138-9-001
CIO .022qF, IkV, 20%Pre-formedPolyester025-103-9-001
CI 1,12470/uF,25V Electrolytic 022-095-9-001
C131.5/iF, 1 OOV P.P.Polyester025-101-9-001
C14.0033/aF, 1 OOV, 20%P.F.Polyester025-105-9-001
CI 5 .047qF, 1 OOV, 10% Polyester025-094-9-001
CI6, 17 lOjuF, 16V,20%Pre-formedTantalum027-010-9-001
C18 15mF, lOV, 20%Pre-formedTantalum027-009-9-001
C19 220/LiF, lOV Electrolytic 022-109-9-001
C201 330pF,500V,10%,PinLead,CeramicDisc020-151-9-001
202 .005aiF, 500V,20%,PinLead,CeramicDisc....020-152-9-001
DIODES
Dl,2,3,4 Diode, lA,600V 151-050-9-001
D5,6 Diode,Protection Silicon 151-054-9-001
D7 Diode, Silicon Low Leakage 151-055-9-001
D8 Diode,1N4007151-053-9-001
D9 Diode,Zener6.2V,5%, 1W(IN4735A) 152-037-9-001
DIO Diode,Zener1N749A (4.3V) 152-062-9-001
Dl 1 Diode, Reference Zener1N4565 (6.4V) 152-066-9-001
TRANSISTORS
} Silicon 2N5818176-051-9-001
Q7, 8,9 PET,N-ChannelClampDiode182-036-9-001
QIO PET,P-Channel182-035-9-001
INTEGRATED CIRCUITS
1C1,1C4CA3130PETOpAmp307-073-9-001
IC2 1C324QuadOpAmp307-060-9-001
IC3 IC30lOpAmp307-074-9-001
IC5 CA3081Transistor Array 037-075-9-001
1C6AY-5-3507307-077-9-001
1C7IC4001Quad Gates 307-072-9-001
1C8IC4016Quad Bilateral Switch307-076-9-001
COMPOSITE
499-086-9-001-B
STEAM POWERED RADIO.COM

SCHEMATIC B 81 K
SYMBOL DESCRIPTION PART NUMBER
NETWORKS
RNl Resistor Network, Input012-011-9-001
RN2 Resistor Network, Display012-007-9-001
RN3 ResistorNetwork012-008-9-001
RN4 ResistorNetwork012-009-9-001
TRANSFORMERS AND SWITCHES
Tl PowerTransformer065-116-9-001
51 Switch, Function083-186-9-001
52 Switch, Range 083-187-9-001
DISPLAYS
DS1,2, 3,4H.P.5082-7650238-008-9-001
MISCELLANEOUS
Fl Fuse 1/8A,3AG Pigtail 193-011-9-001
Fl Fuse 1/16A, 3AG Pigtail (240V Wired Unit) 193-004-9-001
F2 Fuse, 2 Amp,3AG191-251-3-002
Bracket, P.C.Board251-157-9-001
Cover,Top253-042-9-902
Chassis, Main 257-067-9-902
Decorative Inlay (SidePanel)260-063-9-001
Front PanelOverlay260-069-9-001
Bracket, Handle Mounting 261-067-9-001
Case EndPanel, Right 271-041 -9-001
Case EndPanel, Left 271-042-9-001
Terminal Strip345-013-9-001
Fuse Housing,A (2req'd)380-247-9-001
Bezel, Display280-250-9-001
m Filter, Transparentred280-251-9-001
Foot, Front381-059-9-001
Foot, Rear 381-061-9-001
Line Cord420-022-9-001
TestLead, Black 522-062-9-001
TestLead,Red522-063-9-001
Fuseholder/JackAssembly523-115-9-001
Tinnerman (for window) 652-042-9-001
"E" Ring, Bowed(forfusehousing)741-082-9-001
Handle 746-030-9-001
Knob 751-130-9-001
P.C.B., PlasticStandoff759-062-9-001
Spring, Fuse Contact767-038-9-001
Receptacle, Chassis AC770-018-9-001
Banana Jack, Red774-001-9-001
Stand, Wire Form804-005-9-001
NOTE: Standard value resistors arenot listed. Values maybe obtained from
schematic diagram. Minimum charge S5.00per invoice. Orders will be shipped
C.O.D. unless previous open account arrangements iiave been made or remittance
accompanies order. Advance remittance must cover postageorexpress charges.
Specify serial number wiien ordering replacement parts.
B & K-PRi:aS10N • DYNASCAN CORP. • 1801W.BellePlaineAve.• Chicago, IIL 60613
STEAM POWERED RADIO.COM

B & K DivisionofDYNASCAN CORPORATION
2815W,IrvingParkRd.,Chicago,Illinois60618
Phone;312/5834360
FactoryAuthorizedParts& ServiceCenters
492036 - 0 • 777
Thefollowingwillhandleanypartsand/orserviceproblems,eitherinoroutof
warranty.Yournearestservicecenterhasbeenselectedforqualityandprompt
attentiontoyourneeds.Pleasetakeadvantageofthisservicefacilityestablished
foryourbenefit.Thislistissubjecttochangewithoutnotice.Pleasecontact
servicecenterbeforeforwardingequipmentforrepair.
TEST EQUIPMENT
ALABAMA
Arnold'sInstrumentService
2116DauphinIslandPkwy.
Mobile,AL36605
205/478-3230
ARIZONA
ArizonaCertifiedElectronics
2629N.1stAve.
Tucson, AZ85719
602/623-2432
ArizonaElectricStandardLab
1845W.CampbellAve.
Phoenix,AZ85015
602/264-9351
ARKANSAS
ElectronicsSales& Service
7515GeyerSpringsRd.
LittleRock,AR72209
501/565-0774
CALIFORNIA
ElectronicServiceCo.
8128OrionAve.
VanNuys,CA91406
213/780-3071
GuaranteedElectronics
5822MissionSt.
SanFrancisco,CA94112
415/334-5900
TeletekEnterprises,Inc.
2749KilgoreRd.
RanchoCordova,CA95670
916/635-1331
ValleyScientific
P.O.Box7751
5510AirTerminalOr.East
Fresno,CA93727
209/291-6381
CANADA
AtlasElectronicsLimited
50WingoldAve.
Toronto,Ont.,CanadaM6B1P7
416/781-6174
COLORAOO
HouseofTVRepair
1445FlorenceSt.
Aurora,CO80010
303/366-1581
ClydeN.StillElectronics
2630W.Kiowa
ColoradoSprings,CO80904
303/633-8404
CONNECTICUT
L& L Electronics
186N.MainSt.
Branford, CT06405
203/488-4814
DISTRICTOFCOLUMBIA
ElectronicMaintenance
308CarrollSt.N.W.
Washington,DC20012
202/882-2333
FLORIDA
AzaleaParkAppliance,Inc.
1201W.PineSt.
Orlando,FL32805
305/425-1440
EleconCorp.
398639th
St.Petersburg,FL33709
813/522-5451
IDAHO
IdahoInstrumentService
410ElmSt.N.
TwinFalls,ID83301
208/733-5636
STEAM POWERED RADIO.COM

ILLINOIS
OynascanCorp.
2815W.IrvingParkRd.
Chicago,IL 60618
312/5834360
E.I.L. Instruments,Inc.
9708IndustrialOr.
Bridgeview,IL60455
312/430-2292
INDIANA
E.I.L. Instruments,Inc.
7061TwinOaksDr.,SuiteM
Indianapolis,IN46226
317/545-1373
Electro-LabServices,Inc.
510WilliamsRd.
Evansville,IN47712
812/423-5211
KANSAS
MainElectronics,Inc.
225Ida
Wichita,KS67211
316/267-3581
KENTUCKY
LouisvilleMeterService
2829DellBrookeAve.
Louisville,KY40220
502/454-3432
LOUISIANA
TelcomofNewOrleans,Inc.
4239BanksSt.
NewOrleans,LA70119
504/482-8732
MARYLAND
E.I.L. Instruments,Inc.
1830YorkRd.
Timonium,MO21093
301/252-1260
O-Tronics
1237QueenAnneAve.
Odenton, MO21113
301/672-1127
MASSACHUSETTS
ElectricServiceCenter
39MollisSt.
E.Pepperell,MA01437
617/433-6940
MICHIGAN
ElectroInstrumentRepair
Div.InstrumentSpecialties,Inc.
1024West14MileRd.
Clawson, Ml48017
313/435-3311
MICHIGAN(cont'd)
MainElectronics
5558S.PennsylvaniaAve.
Lansing, Ml48910
517/882-5035
MISSOURI
LaneElectronics,Inc.
3805Chouteau
KansasCity,MO64117
816/455-0308
KermitShetleyRepair
2031WoodlandHillsOr.
CapeGirardeau,MO63701
314/334-2055
ScherrerInstruments
7170ManchesterAve.
St.Louis,MO63143
314/644-5362
NEBRASKA
Alpha-OmegaAppliedElectronics,Inc.
2208FranklinSt.
Bellevue,NE68005
402/291-2200
Bob'sIndustrialElectronics
1720N.Sherman
NorthPlatte,NE69101
308/532-8017
ElectrometricsCo.
404South11th
Lincoln, NE68508
402/477-3434
MidwesternLaboratories
14965GroverSt.
Omaha,NE68144
402/334-5606
NEWJERSEY
HosicaLaboratories
715MainSt.
NorthCaldwell,N.J.07425
201/256-7724
NEWMEXICO
BradleyElectronics
6344Linn,N.E.
Albuquerque,NM87100
505/268-6930
NEWYORK
AltairElectronicsService,Inc.
474ThurstonRd.
Rochester,N.Y.14619
716/235-1470
STEAM POWERED RADIO.COM

NEWYORK(cont'd)
CircleTele-Tronics,Inc.
1008UticaAve.
Brooklyn, N.Y.11203
212/345-5656
NORTHCAROLINA
MusicCenterRepairs
213EastMainSt.
Cherryville,N.C.28021
704/435-5304
SpeedInstrument
Oiv.Owen-Barbot,Inc.
Hwy.#401NorthBox11456
Raleigh, N.C.27604
919/876^919
OHIO
E.I.L. Instruments,Inc.
7915SouthSuburbanRd.
Oayton, OH45459
513/435-2134
PioneerCleveland
Oiv.PioneerStandardElectronics,Inc.
4800E.131St.
Cleveland, OH44105
216/587-3600
PioneerDaytonInstrumentLab
1900Troy
Oayton, OH45404
513/236-9900
OKLAHOMA
Stark'sAvionics& Comm.Service
1604N.E.Woodlands
PoncaCityAirport
PoncaCity,OK74601
405/765-8264
OREGON
Westcon
1910N.KillingsworthSt.
Portland, OR97217
503/285-6629
PENNSYLVANIA
AmericanInstrumentService,Inc.
44145N.5thSt.
Philadelphia,PA19123
215/923-6760
Oynatronics,Inc.
Route611
Tannersville,PA18372
717/629-0050
E.I.L. Instruments,Inc.
1844Ardmore Blvd.
Pittsburgh,PA15221
412/731-5230
RHODEISLAND
E.I.L. Instruments,Inc.
6810PostRd.
NorthKingstown,R.I.02852
401/885-1773
SOUTHCAROLINA
King's
114S.MainSt.
Bishopville,S.C.29010
803/484-5482
TENNESSEE
InstrumentRepairService
468N.Watkins
Memphis,TN38104
901/278-0762
TEXAS
BorderElectronicsServices
1704E.Paisano
P.O.Box3804
ElPaso,TX79923
915/532-2524
CentralInstrumentLaboratory
777S.CentralExpressway
Richardson,TX75080
214/234-2862
ChampionInstrumentLaboratory
624S.TatarRoad
Pasadena,TX77506
713/473-6680
TheMeasurementsCompany
8100S.Kirkwood,Suite105
Houston, TX77072
713/498-7478
MooreElectronicService,Inc.
3511Pinemont,SuiteA-4
Houston, TX77018
713/682-4430
OsmondAssociates
1716E.Yandell
ElPaso,TX79902
915/542-0024
WhitlockInstrument
1306NorthTexasStreet
Odessa,TX79762
915/337-3412
UTAH
SaltLakeInstrumentsService
129W.17thSouth
SaltLakeCity,UT84115
801/487-2541
STEAM POWERED RADIO.COM

VIRGINIA
E.I.L. Instruments,Inc.
5400CherokeeAve.
Alexandria,VA22312
703/354-4330
WASHINGTON
B&FRepair
E.15110Sprague
Veradale,WA99037
509/926-9037
Eicher-RichardsCo.
2727N.E.BlakeleySt.
Seattle,WA98105
206/523-7888
TheLectronicShoppe
202W.MainSt.
Everson, WA98247
206/966-3621
Sutherlands,Inc.
952IndustryOr.
Building26
Tukwila,WA98188
206/575A075
WISCONSIN
Electro-MechanoCo.
241E.ErieSt.
Milwaukee,Wl53202
414/272^050
PUERTORICO
E.I.L. Instruments,Inc.
Marginal, A12
UrbanizationLosAngeles
Carolina,PuertoRico00630
809/791-4115
SOUTHAMERICA
TeleromanCIALTOA
10deAgosto614y Boyaca
Guayaquil,S.A.
Ecuador
513--525Casilla3906
AUSTRALIA
Parameters,PTY,LTO.
P.O.Box480
CrowsNest, N.S.W.
Australia2065
Oynascan Corporation— 6460 W.Cortland— Chicago, Illinois 60635
PrintedInU.S.A.
STEAM POWERED RADIO.COM