Kenwood MS-1660 User manual

MS-1660
(DIGITALMEMORY SCOPE)
INSTRUCTION MANUAL

SAFETY
Symbol in This Manual
A
This symbolindicateswhereapplicablecautionary
orotherinformationistobefound.
Power Source
This equipmentoperates from a powersourcethatdoes
notapplymorethan250V rmsbetweenthesupplycon-
ductorsorbetweeneithersupplyconductorandground.
A protectivegroundconnectionbywayofthegrounding
conductorinthepowercordisessentialfor safe operation.
Grounding theProduct
This equipmentisgrounded through thegroundingcon-
ductorofthepowercord.Toavoidelectricalshock,plug
thepowercord into a properlywiredreceptaclebefore
connectingtotheequipment input or output terminals.
Use theProperPowerCord
Use onlythepowercordandconnectorspecifiedforyour
product.
Use theProper Fuse
To avoidfirehazard,usea fuseofthecorrecttype.
DonotOperatein Explosive Atmospheres
To avoidexplosion,donotoperatethisproductinanex-
plosive atmosphere.
DonotRemoveCoverorPanel
To avoidpersonalinjury,donotremovethecoverorpanel.
Refer servicingtoqualifiedpersonnel.
VoltageConversion
Ifthepowersourceisnotappliedtoyourproduct,contact
yourdealer.Toavoidelectricalshock,donotperform
thevoltageconversion.
CONTENTS
SAFETY 2
FEATURES.... 3
SPECIFICATIONS 4
PREPARATION FORUSE6
CONTROLS ANDINDICATORS7
FRONT PANEL 7
REAR PANEL 14
OPERATION 16
OPERATION ASAN OSCILLOSCOPE 16
(1)NORMAL SWEEP DISPLAY OPERATION18
(2)MAGNIFIED SWEEP OPERATION 18
(3) X-Y OPERATION 18
MEMORY SCOPE OPERATION19
(1)WAVEFORM OBSERVATION 19
(2)READINGTOPEN RECORDER 21
(3) CONTROLBY GP-IB 21
APPLICATION 23
APPLICATION ASAN OSCILLOSCOPE 23
APPLICATION ASA DIGITALMEMORY SCOPE... 32
Power InputVoltageConfiguration34
2

FEATURES
The digital memoryscopeMS-1660consistsofaDC-20MHz
bandwidth,dual-traceoscilloscope with a built-in digital
memory.Thememoryfeaturesa capacityof8 bitsx 2048
wordsperchannelanda maximumwritespeedof1 JUS/
word.The unit providestheabilitytostoreandreproduce
sporadic, transientandrepetitiveevents,andrearthe
storedsignalsouttoa penrecorder, through simpleopera-
tion.
The contentsofthememorycanbereadoutor written
via GP-IB sothatexternaldatacanbemonitoredonthe
CRT screenbystoringthedatainthememory. Since an
independentsamplingclockisprovidedforeach
channel, separatesignalscanbestored with separate
clocks atthesametime,andthesamesignalscanbe
storedata lowspeedanda highspeedatthesametime.
A singletracecanbeusedas4Kwords.
1. Foreachtrace,a memoryspaceof2kwordsispro-
vided. The unit hastwoindependentsemiconductor
memoriesof8 bitsx 2048words each.
2. Dualchannel
Inputconsistsoftwoeventsata time,eachallotted
an independentmemory space. Maximumwritespeed
is 1 jus/word.
3. Dualclock
Two completelyindependentsamplingclocksarepro-
videdtoallowsimultaneousstorageoftwo totally
unrelatedsignals.Also,thesamesignalcanbestored
atlowspeedandhighspeed(equivalentofpartial
magnification)atthesametime.
4. Minusdelayfunction
The unit iscapableofstoringthesignalsproduced
beforea triggerpulse,whicharenotobservableon
oscilloscopes.
The dataafterthedelayset point canbeobservedon
theotherchannel,bymagnificationorcontraction.
The delayset point iscontinuouslyvariable with cursor
indication.
5. Hardcopy
The penrecorderprovidedcanbeusedtoproducethe
hardcopyofthedisplayedwaveform from memory.
Inaddition,penfreerunfunctionisprovidedforauto-
matic repetition ofsignalstorageandcorresponding
hardcopyreproduction.
6. Twostoragemodesareselectable.Therefreshmode
initiates writing with a triggersignal.Inthepretrigger
mode,theterminationof writing iscontrolled with a
triggersignal,ineithermode,thewaveform following
thecursor point canbeviewedinmagnifiedorcontract-
ed form intheotherchannel.
7. Free runfunctionforautomatic repetition ofread/write
operations
Once written,thesignalsareheldina readstateforup
to20sec,thenentera writablestateinwhichthe
signals waitfora triggersignal. This cycleisrepeated
automatically.
8. Memorybackupfunction
Signals storedremainunchangedinthememoryeven
after turning poweroff. Thus waveformsmaybe ana-
lyzed atanytimeonlater days.
9. Withthe GP-IB interface,thedata within inmemorycan
besentout,andexternaldatacanbe written inthe
memoryfordisplayonthe screen.
10. Linesynchronizationfacilitatestheobservationand
storageofthesignalsthataretriggered with theline
frequency.
11. BysettingthemodetoX-Y,the unit changestoanX-Y
oscilloscope with a one-button operation.
12. A rectangular,largesizedCRT with widerdisplay
area providesfull-screensignalobservation.
13. Thevertical axis providesa highsensitivityof1 mV/div,
plusa widebandrange from 5mV/divtoa desiredset-
ting.
14. The unit iscapableofhigh-speedsweepof20ns/div.
15. A 150mmrectangularCRT with internalgraticule
(domedmeshtype,post-acceleration with 6kVacceler-
ationvoltage)provides easy waveformobservation
without parallax.
16. The0,10,90,and100%marksonthescreenprovides
easy measurementofrisetime.
17. Theangleofhorizontaltracecanbeeasilycorrected
with trace rotation controlsonthe front panel.
18. The scale illuminationfacilitatesmeasurementina
darkplace,andalsoenablesphotographicrecording
oftheon-screenwaveform.
19. Withtheautomaticfreerunfunction,thetracecanbe
checked whilenosignalisfed.
20. CH1 OUTPUT terminalsareprovidedto monitor the
input signalsontheCH1.
3

SPECIFICATIONS
4
CRT
Model:150 FTM31: Rectangular, with
internalgraticule
Acceleration voltage:6 kV
Display area: 8 X10div(1div= 10mm)
VERTICAL AXIS(CommontoCH1andCH2)
Sensitivity: 1 mV/divto5V/div± 3%
Attenuator:5 mV/divto5V/div
1 -2-5 sequence, fineadjust-
mentbetween10ranges
Inputimpedance:1 MSI ± 2%,Approx.25pF
Frequence responce:
DC: DCto20MHz(Within- 3 dB
at5 mV/divto5V/div)
DC to10MHz(Within-3dB
atX5 GAIN)
AC: 5 Hzto20MHz(Within-3dB
at5 mV/divto5 V/div)
5 Hzto10MHz(Within-3dB
atX5 GAIN)
Rise time X1: Less than17.5ns
X5 GAIN: Less than35ns
Crosstalk: Less than-40dB(CH1& CH2
insamerange)
Operatingmodes:
CH1 CH1, singletrace
CH2 CH2,singletrace
DUAL CH1andCH2,dualtrace
ADD CH1+ CH2(added)display
ALT Dualorquadtracealternating
CHOP Dualorquadtracechopped
X-Y X-Yoscilloscope
CHOP frequency:Approx.250kHz
Polarity reversal: AvailableforCH2only
Maximum input voltage:500Vp.por250V
(dc + acpeak)
Maximumundistorted
amplitude:8 div,minimum
(DC to20MHz)
HORIZONTAL AXIS(Channel2 input,exceptX10MAG)
Modes: X-Ymodeisswitchselectable
CH1: Yaxis
CH2:Xaxis
Sensitivity: Same asvertical axis (CH2)
Inputimpedance: Same asvertical axis (CH2)
Frequency response:
DC: DCto1 MHz(Within-3dB)
AC: 5 Hzto1 MHz(Within-3dB)
X-Y phasedifference: Less than3°at100kHz
Maximumallowable input
voltage: Same asvertical axis (CH2)
SWEEP
Sweep: NORM;Triggersweep
AUTO; Automaticfreerun
functionwhilesignalsarenot
fed
Sweep time:0.2jus/div.to0.5s/div± 3%,
in1-2-5sequence with in20
ranges, fineadjustmentbe-
tween20ranges
Sweep magnification:X10± 5%
Linearity: ± 3%(0.2jus/div± 5% with
X10 magnification)
TRIGGERING
CH1: Triggered with vertical input
signal onCH1.
CH2: Triggered with vertical input
signal onCH2.
EXT: Triggered with external
synchronizing signal.
LINE: Triggered with linefrequency
External triggering:
Inputimpedance:1 Mft± 2%,Approx.25pF
^Maximum input voltage:50V (DC+ ACpeak)
Couplingmodes:AC, HFREJ , DC
Sync sensitivity
PROBE CALIBRATING VOLTAGE
0.5V ± 2%ofpositivesquare wave, approx.1 kHz
INTENSITY MODULATION
Inputvoltage:Intensity increases with TTL
level.
Inputimpedance:Approx.10kft
Frequency range:DCto5 MHz
Maximum input voltage:50V (DC+ ACpeak)
VERTICAL AXISCH1signal output
OUTPUT
Outputvoltage:Approx.50mV/div(50ftload)
Outputimpedance:Approx.5012
Frequency response:
X1: 100Hzto20MHz(within± 3
dB), at50ft load
X5 GAIN: 100Hzto10MHz(within±3
dB),at 50ftload
SYNC
SYNC. FREQ.
MIN. SYNC AMPLITUDE
(VOLTAGE)
COUPLING
RANGE
INT EXT
DC DC
~ 20MHz
1 div 0-1vp.p
AC
10Hz ~ 20MHz 1 div 0-1vp.p
DC
HFREJ
At1.5kHzorover,min.amplitude(voltage)
requiredfor sync increases.

5
GATE OUTPUT
Outputwaveform:Positivepulsetriggeredto
sweep
Outputvoltage:TTLlevel
Series resistance:Approx.22012
DATA CONVERTER
Convertingmethod: Successive comparison,
A/D converter
Conversion speed:1 jus/word
Resolution: 8 bits (0.4%)
Frequency response:DCto250kHz(within-3dB)
MEMORY
Memorycapacity:8 bitsX 2048words/CHX2
(Full memorycapacityof4096
words)
Memorydevices:C-MOSstaticRAMs
Writespeed:1 Ms to100ms/word, with
1-2-5stepsin16ranges(with
independentchannelsetting)
Read speed
INT: MEMORYOUT:1 jus/word
(fixed)
SCOPE: 1 /is/word(fixed)
FOR PEN: 10,20,50ms/word
(3 ranges)
EXT: TTLlevel,repetitivesquare
wave of less than1 MHz
High-levelpulsewidth;
Morethan500ns
Low-level pulsewidth;
Morethan500ns
Rise time; Less than500ns
FREEZE function:Rewrite-protectableforeach
channel
Memorybackup:Fullmemoryholding.
Holdingtimeofmorethan200h.
OPERATING FUNCTIONS
REFRESH : Writeisstarted with thetrigger
(TRIG START) signal(ormanually).
Write prohibition variabletime
between1 to20sec (DISPLAY
TIME)
PRE TRIG: A writeisstartedmanually.
(MANUAL START) Performspretriggeroperation
(negativedelay)accordingto
cursor setting.Automatic,re-
peatedwrite/readoperations
are available(readtimecanbe
DELAY: set from approx.1 to20 sec).
address issimultaneouslydis-
playedinotherchannel.
Cursor settingCursoriscontinuouslymovable
within addressesbetween2 and
2000 words.
Shiftingresolution1 word
(speed variablein2 steps)
DATA OUTPUT
D/Aconverter: 8-bit resolution
Outputlevel:MEMORYOUT:1.6Vp-p± 3%
relativeto input full scale
FOR PEN:2.0Vp-p± 3%
relativeto input full scale
(Over 1 k!2load)
Outputimpedance:MEMORYOUT:Approx.2212
CONTROL OUTPUT
READ GATE OUT
Outputwaveform:Positivepulseequivalentto1
wordoflastaddress
Outputvoltage:TTLlevel(Commonto both
channels)
Series resistance:Approx.22012
READ GATE OUTFORPEN
ControlsignalforPEN
Outputsignal:Negativelogic(activatedabout
2 secafterpenstartON)
Outputvoltage:TTLlevel
Series resistance:Approx.22012
EXTERNAL CONTROL
The datainmemoryiscontrollablevia GP-IB.
Governingstandard: IEEE STD488-1978
Subsets tobe used: SH1, AH1, TE0, LEO, T6,L4,
SR1, RL1, PP0, DC1,andDT0
POWER SOURCE
Line voltage 100/120/220/240Vac ± 10%,
50/60Hz
Power consumptionApprox.70W
DIMENSIONS
Width 426mm(433mm)
Height177mm(190mm)
Depth411mm(475mm)
Figures in( ) includesproject-
ingparts.
WEIGHT Approx.13kg
ENVIRONMENT
Operatingtemperatureand
humidity forguaranteed
specifications: 10to35°C,85%RHmax.
Full operatingtemperature
and humidity range:0 to45°C,85%RHmax.
ACCESSORIES
Probe (PC-20) 2
Attenuation:1/10,1/1
Inputimpedance1/10:10M12,below18pF
1/1: 1 M12,below100pF
Instructionmanual:1
AC powercord:1
Replacement fuse:1
OPTION GP-IB cable (CB-2420P)

PREPARATION FORUSE
SAFETY
Before connectingtheinstrumenttoa powersource,
carefully readthe following information,thenverifythat
theproperpowercordisusedandtheproperlinefuseisin-
stalled forpowersource.Thespecifiedvoltageisshownat
the right sideofthepowerconnectorontherearpanel.If
thepower-cordisnotappliedforspecifiedvoltage,thereis
always a certainamountofdanger from electricshock.
Line voltage
This instrumentoperatesusingac-power input voltages
that100/120/220/240V atfrequencies from 50Hzto
60 Hz.
Power cord
The groundwireofthe3-wireacpowerplug places the
chassis andhousingofthememoryscopeatearthground.
Do notattempttodefeatthegroundwireconnectionor
floatthememoryscopetodosomayposea greatsafety
hazard. Theappropriatepowercordissuppliedbyan
option thatisspecifiedwhentheinstrumentisordered.
The optionalpowercordsareshownasfollowsin Fig. 40.
Line fuse
The fuseholderislocatedontherearpanelandcontains
theline fuse. Verifythattheproperfuseisinstalledby
replacing theline fuse.
EQUIPMENT PROTECTION
1. Before putting thisinstrumentinuse,makesurethat
thepowersourceselectorswitchissettotheproper
positionthatcorrespondstothelinevoltage.Ifthe
selector switchisnotproperlyset,this causes damage
totheinstrument.Connectthepowercordtothe
powerreceptacleonlyafterthisconfirmationismade.
2. TheMS-1660shouldbeinstalledata placemeetingthe
following conditions:
oTheMS-1660isnotexposedtodirectsunlight.
oTemperatureand humidity arenotveryhigh.Theair
does notcontainmanydustparticles,
oThesurroundingfacilitiesandequipmentdonot
produceintensemechanicalvibration,magneticforce,
orimpulsevoltage.
3. Neverapplymorethanthemaximumratedvoltageto
theoscilloscope input jacks.
CH1, CH2 input jacks:
500Vp-p or250V(DC+ ACpeak)
AEXT TRIG, Z AXIS input jacks:
50V (DC+ ACpeak)
Never applyexternalvoltagetotheoscilloscope output
terminals.
4. Whendesiringtoretainthestoredwaveformwhilethe
instrumentispoweredoff,pushthe FREEZE switch
before turning offthepower. Keep the FREEZE switch
pressed whilethepoweristurnedoff.Itisdesirable
tokeepthe FREEZE switchpressedwhentheinstru-
mentispoweredonagaintoreproducethestored wave-
form.Notethat,if input signalsourceisinconnection
with theinstrumentwhenthepoweristurnedon,the
storedwaveformwillbe erased bythewriteoperation
started with an input signal.
The upper3 bitsofthe address switchesfor GP-IB must
be settothelowerpositions.
5. Donot increase theintensitymorethanrequired.
6. Neverallowa smallspotofhighbrilliancetoremainon
the screen forextendedperiodsoftime.
7. WhenusingthisinstrumentinX-Ymode,setthe PULL-
X10MAG switchtothe PUSH position.Ifthisswitchis
set tothe PULL position,thewaveformmaybedisturb-
ed bynoise.
8. Nevercovertheventilatingholesinthetopofthe scope,
as thiswill increase theoperatingtemperatureinsidethe
case.
9. Whenremovingthe case, observethemaintenancein-
structioncontainedinthismanualtopreventa safety
hazard because thisinstrumentcontainshighvoltage
circuits.
10. Always groundtheinstrumentusingthe FRAME sideof
theGNDterminalsontherearpaneltopreventa safety
hazard.
11. When turning onandoffthe POWER switchrepeatedly,
keep anintervalofabout5 seconds. Faster onandoff
operationmay cause malfunctiontotheinstrument.
6

CONTROLS ANDINDICATORS
Fig. 1
FRONT PANEL
©POWER, SCALE ILLUMControl
Turns power on/off andvariesgraticulebrightness.
©POWERLEDPilotLamp
Indicates thatthepowersupplyhasbeenturnedon.
®J=
Groundterminal.
©CAL
Provides a positive0.5Vpeak-to-peaksquarewave
signal ofapprox.1 kHzforprobecompensationadjust-
ment.
© TRACE ROTATIONControl
Electrically rotatesthetracetohorizontalposition.
Used aswhenthetraceis tilted byterrestrialmagnet-
ism.
© FOCUS Control
Used toadjustthetracefor optimum focus.
©INTENSITY/ASTIGControl
INTENSITY: Adjuststhetraceintensity.
ASTIG: Astigmatismadjustmentprovides optimum
spotroundnesswhenusedinconjunction
with FOCUS control
© INPUT Jack
Vertical input forchannel1 traceinnormalsweep
operation.Vertical input forX-Yoperation.
©AC-GND-DCSwitch
Three-positionswitchwhichoperatesasfollows:
AC: Inputsignaliscapacitivelycoupled,blocking
DC component.
GND: Opensthepathbetweenthe input jackand
verticalamplifierssothatthe input ofvertical
amplifierisgrounded. This allowstheearth
potentialtobechecked.
DC: Inputsignalisdirectcoupled,allowingobserva-
tion ofwaveformcontainingDCcomponent.
7

Fig. 2
@ VOLTS/DSV Control
Vertical attenuatorforchannel1.Providesstepadjust-
mentofverticalsensitivityin1-2-5sequence. VARI-
ABLE controlisturnedtotheCALposition,the
calibratedverticalsensitivityisobtained.ForX-Y
operation,thiscontrol serves astheattenuatorfor
Y axis.
@ VARIABLE/PULL X5GAINControls
VARIABLE:
RotationprovidesfinecontrolofCH1vertical sensi-
tivity. Inthefullyclockwise(CAL)position,the
verticalattenuatoriscalibrated.ForX-Yoperation,
thiscontrol serves for X-axis attenuationfineadjust-
ment.
PULL X5 GAIN:
Whenpulledout,the VOLTS/DIV settingis multiplied
byfive,andforX-Yoperation,the X-axis sensitivity
is multiplied accordingly.InX5GAINmode,increas-
edverticalgainmakesthetracethiker.
@y POSITIONControl
RotationadjustsverticalpositionofCH1waveformon
the screen. ForX-Yoperation,thiscontroladjustsY
axis position.
Inmemoryscopeoperation,thecontrolprovidesDC
OFFSET adjustmentofCH1,superimposingtheDC
level over input signal.
Clockwise rotation ofthecontroladds+DCleveltothe
GND level.Counterclockwise rotation adds-DClevel
totheGNDlevel.
@y MEMORYPOSITIONControl
Adjusts theverticalpositionofthestoredwaveform.
Withselectionofthe SAMPLING CLOCK A Control,
thiscontroladjuststheverticalpositionofthestored
waveform.FormemoryoperationinX-Ymode,the
controladjusts Y-axis position.
NOTE:
This controlhasnoeffectonMEMORYOUTA @ jack.
@ INPUT Jack
Receives CH2vertical input, or X-axis input inX-Y
operation.
©AC-GND-DCSwitch
Selects thecouplingofchannel2 vertical input signal.
InX-Yoperation,theswitchprovides input selection
of X-axis andperformsthesamefunctionas AC-GND-
DC®for CH1.
@ VOLTS/DIVControl
Vertical attenuatorforCH2.Providesthesamefunc-
tion as VOLTS/DIV Control© forCH1.InX-Y
operation,thecontrol serves asthe X-axis attenuator.
@ VARIABLE/PULL X5GAINControl
Provides thefinecontroloftheverticalattenuationfor
CH2 andincreasestheverticalsensitivity.Thecontrol
performsthesamefunctionas VARIABLE/PULLX5
GAIN Control(R)forCH1.InX-Yoperation,the
controlprovidesthefineadjustmentofthe X-axis
attenuationandincreasesthe X-axis sensitivity.
8

@ ^ POSITIONControl
For CH2,thecontrolprovidesthesamefunctionas
^ POSITION Control@ forCH1.InX-Yopera-
tion,thecontrolprovides X-axis positionadjustment.
Inmemoryscopeoperation,thiscontrolprovidesDC
OFFSET adjustmentforCH2.
@ ^MEMORYPOSITIONControl
Withselectionofthe SAMPLING CLOCK B control,
thiscontroladjuststheverticalpositionofthestored
waveform.FormemoryoperationinX-Ymode,the
controladjuststhe X-axis position.
NOTE:
This controldoesnotworkforMEMORYOUTB @ jack.
@ MODESwitch
Selects theoperationmodeofthevertical axis.
CH1: Onlythe input signaltochannel1 isdisplayed
onthe screen. Inmemoryoperation,a
differentdisplayisproducedonthescreen
accordingtotheselectionof NORM/DELAY
selector of DISPLAY MODE@ switches.
NORM: Thewaveformstored with SAMPLING
CLOCK A isdisplayedonthe screen.
DELAY:The waveformsstored with SAMPLING
CLOCK A andB aredisplayedasdualtraces
onthe screen.
CH2: Onlythe input signaltochannel2 isdisplayed
onthe screen. Inmemoryoperation,a dif-
ferentdisplayisproducedonthescreen
accordingtotheselectionof NORM/DELAY
selector.
NORM: Thewaveformstored with SAMPLING
CLOCK B isdisplayedonthe screen.
DELAY: The waveformsstored with SAMPLING
CLOCK A andB aredisplayedasdualtraces
onthe screen.
DUAL: The input signalstochannel1 andchannel2
are displayedonthe screen. Inmemory
operation,thewaveformsstored with SAMPL-
ING COCK A andB aredisplayedonthe
screen.
DELAY operationwillnotbeproducedbut
onlyNORMoperationwillbeperformedeven
ifthe NORM/DELAY selectorissetto
DELAY.
ADD: ThealgebraicsumofCH1andCH2signalsis
displayedonthe screen. WhentheCH2INV
21 button isengaged,thedifferencebetween
CH1 andCH2signalsisdisplayed.
Inmemoryoperation,a differentdisplayis
producedaccordingtotheselectionof
NORM/DELAY selector.
NORM: Thescreendisplaysthewaveformwhichis
stored with SAMPLING CLOCK B asthe
ialgebraicsumofCH1andCH2signals(oras
thedifferencebetweenCH1andCH2signals
whenCH2INVisselected).
DELAY: Thescreenprovidesa dualtracedisplaythe
wave formswhicharestored with SAMPL-
ING CLOCK A andB asthealgebraicsumof
CH1 andCH2signals(orasthedifference
betweenCH1andCH2signalswhenCH2INV
is selected).
X-Y: TheinstrumentoperatesasanX-Yoscillo-
scope with CH1servingas Y-axis andCH2as
X-axis.
Inmemoryoperation,thewaveformstored
with SAMPLING CLOCK A isdisplayedas
Y-axis input, andthewaveformstored with
SAMPLING CLOCK B isdisplayedas X-axis
input.
The DELAY operationwillnotbeproduced
butonlytheNORMoperationwillbepro-
ducedevenifthe NORM/DELAY selectoris
set to DELAY.
J-ALT/m CHOP Selector:
Selects thedisplaymodefortwotracesinthe
DUAL mode.
JL ALT:CH1andCH2aignalsarealternatelydisplay-
ed.
m CHOP: CH1andCH2signalsaredisplayedbychop-
ping.
Inmemoryoperation,thealternatesweep
modeisautomaticallyselectedregardlessof
thesettingofthisselector.Settingtodisplay
thestoredwaveformonthe screen.
NOTE:
Each ofthemodesettingcontrolsisrelatedtothe writing
into memory.Seethedescriptionson DISPLAY MODE,
REFRESH/PRE TRIG, NORM/DELAY, SAMPLING
CLOCK A,B,and CURSOR.
@ CH2INVButton
Inverts thepolarityofCH2signal.
@ EXTTRIG Jack
Whenthe SOURCE controlissettotheEXTposition,
thesweepistriggeredbythe input signalfed through
thisjack.
@ LEVEL/PULL SLOPE (-)Control
LEVEL: Adjuststhetriggerlevel,i.e.,the point onthe
triggersignalwaveformslopewherethesweep
starts.
PULL SLOPE:
Adjusts thepolarityofthetriggering.When
thecontrolispulledout,thetriggeroccurs
atthetrailingedgeofthe input waveform.
@ COUPLINGSwitch
Selects thecouplingforthe triggering signal.
9

Fig. 3
AC: The trigger signaliscapacitivelycoupled with
the trigger circuit.
The DCcomponentof input signalisblocked.
HFREJ: TriggersignalisDCcoupled with the trigger
circuit.
AC componentsover1.5kHzareattenuated
forstable triggering oflow-frequencycom-
ponents.
DC: The trigger signalisDCcoupled with the
trigger circuitinsucha wayastogivea trig-
geringwhichincludestheeffectsofdccom-
ponents.
@ TRIG'DLamp
Lightsupwhenthe triger signalisfedandreachesthe
triggering rangeset with the LEVEL control (23).
@ SOURCE Switch
Allowsselection from three triggering modes.
CH1: CH1vertical input signalbecomesa trigger
signal.
CH2: CH2vertical input signalbecomesa trigger
signal.
EXT: Signalappliedat EXT.TRIG (22)jackbe-
comes a trigger signal.
LINE: Linefrequencyofthecommercialsource
becomesa trigger signal.
(27)TRIGGERINGMODESwitch
Selects triggering mode.
AUTO: Triggeredsweepoperation. Even without a
trigger signal,the unit performsfreerun,
showinga trace.
NORM: Normal triggered sweepoperation.Notrace
will bepresentedwhena proper trigger signal
is absent.
Whilethestoredwaveformisdisplayedonthe
screen, onlythestoredwaveformisdisplayed
onthescreen without performing theNORM
operation.
(28) SWEEP TIME/DIVControl
Selects thesweep time in20steps from 0.2/is/divto
0.5s/div.Thesweep time will betheindicationvalue
calibratedattheCAL position (fullclockwise)of
VARIABLE (2§). Whilethestoredwaveformisdis-
puted onthe screen, theindicationonthis control
has noeffect.
@ VARIABLE Control
Provides finesweep time adjustmentcontinuously
betweentherangesofthe SWEEP TIME/DIV Control
(28) . Thesweep time iscalibratedintheCAL position
(fullclockwise).Whilethestoredwaveformisdisplay-
edonthe screen, this control hasnoeffect.
(30)ikPOSITION/PULLXI0MAGControl
4k POSITION:
Rotationadjustshorizontal position ofthe
waveform.
PULL X10MAG:
Provides 10timesfastersweep time when
pulledout.
10