Tektronix 7A18, 7A18N Instruction Manual

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Tektronix,

Inc

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7A18/7A18N

SECTION

SECTION

SECTION

SECTION4

1

SPECIFICATION

Introduction

Electrical

7A18

And

Response

Environmental

Physical

2

OPERATING

Installation
Front

Panel

General

Basic

Applications

3

CIRCUIT

Introduction

Block

Diagram

Detailed

MAINTENANCE

Preventive

Troubleshooting

Replacement

Component

Characteristics

Mainframe Frequency

Characteristics

Characteristics

INSTRUCTIONS

Controls

Operating

and Connectors

Information

DESCRIPTION

Description

Circuit

Description

Maintenance

Parts

Replacement

Page

1-1

1-1

1-3
1-3
1-3

2-1
2-1
2-2
2-4

3-1
3-1

3-1

4-1
4-1
4-3
4-4

OPTION

SECTION

SECTION

SECTION8

CHANGE

INFORMATION

6

ELECTRICAL
Abbreviations

Parts

DIAGRAMS

7

ILLUSTRATIONS

Symbols
Voltage

MECHANICAL

Mechanical

Index
Mechanical
Accessories

INFORMATION

Ordering

and

and

Parts

of

Mechanical

Parts

PARTS

and

Symbols

Information

AND

CIRCUIT

Reference

Waveform

PAR'I'S

List

List

LIST

BOARD

Designators

Conditions

LIST

Information

Parts

Illustrations

SECTION

5

CALIBRATION
Recalibration

Test
Part

PartII--

Equipment

I-.-

Performance

Adjustment

Interval

Required

Check

5-1
5-1

5-3
5-7

REV.JUNE

Abbreviations
or

taken

directly

Symbols
the

for

electronics

locatedatthe

1974

and

symbols

from

Units",

MIL-STD-12B

industry.Change

rearofthis

used

IEEE

manual

in this

manual

Standard

and

260

other

are

standardsof.

information,ifany,

.

based on

"Standard

is

7A18/7A18N

Fig.1-1

.

7A18

and

7A18N

Amplifier

.

7A18/7A18N

Introduction

The

7A18

units

are

designed
Oscilloscopes
tical
"IDENTIFY"
references
unless
medium-bandwidth
tion

circuits

Deflection

.

except

made

otherwise noted.The

are

Characteristic

Factor

Change

and

7A18N

for use

The

7A18

that

readout

function

are

to the

7A18

amplifier.Internal

automatically

information,

Dual

with

and

7A18N

encoding

provided onlyinthe

apply

if

Trace

Tektronix

are

equally to the

7A18

switched

any,

Amplifier

capabilities

isadual-channel,

gain

affecting

7000-Series

electrically

7A18.All

and

compensa-

to

correspond

Performance

this

plug-in

iden-

and

7A18N

TABLE

ELECTRICAL

section

an

to

willbefound

the

setting

inverted
operated

Oscilloscopes

The
stated
ambient
minute

1-1

Requirement

at the

of the

for differential

in

any
.

following

environmental

temperature

warmup

unless

rearofthe

VOLTS/DIV

plug-in

electrical

range

of

+20°C

otherwise

manual

switch

measurements

compartment

characteristics

for

instruments

+30

to

noted,

.

.

Channel2can

.

The

7A18

of the

7000-Series

are

valid

calibratedatan

°C,and

afterafive

can

over the

be
be

Calibrated

Deflection

Uncalibrated
(VARIABLE)

GAIN

Frequency
System
(8

div

reference
Upper
DC

Lower
AC

With

Range

Factor

Response

Dependent

signal)

Bandwidth

(Direct)

(Capacitive)

Coupled

Bandwidth

10X

Probe

Accuracy

Coupled

5

mV/Div

2,5sequence

Within

2%

0.mV/Div

Continuously
steps

;

extends

least12.5

See

Table

10

Hertzorless

1

Hertz

or

to5V/Div;ten

.

with

GAIN

. .

._

._

. .

.__.._ .

variable

deflection

V/Div

.

A

less

steps

adjusted

between

factortoat

in a

1,

at

calibrated

Permits
for

calibrated

series

adjustment

operation

oscilloscopes

of deflection

with

.

all

factor

7000-

Specification-7A18/7A18N

TABLE

1-1

(cont)

Maximum

Channel

Input

Displayed Noise

Overdrive

InputVoltage

DC

Coupled

AC

Coupled

Isolation

R

and

Resistance

Capacitance

RC

Product

(Tangentially

Recovery

Characteristic

C

m..

Measured)

Time

Performance

50:1display

megahertz

1

MQ±2%~

-

Approximately

ratioupto

.

20.0pf

Requirement

50

Supplemental,

volts,

250
ponent500

mum,

500
nent
mum,

Within
factors

300
7000-Series

0.1msorlesstorecover
division
drive

---75

signal

(DC+Peak

volts

one

kilohertzorless

volts,

(DC+Peak

500

volts

one

kilohertz

:,_

1%

.

microvoltsorlessat5

Oscilloscope

after

signalofup

divisions

duration

Information

peak-to-peak

peak-to-peak

or

between

removal

the

to

regardlessofoverdrive

.

AC);AC

AC);AC

less

+75

com-

maxi-

.

compo-

maxi-

.

all

deflection

mV/Div

.

to

within

of an over-

divisions

-"

in

one

or

Common

Drift

DC

Drift
temperature
constant)

Drift

(line

Time

Display

Mode

Rejection

with

Time

and

with

Temperature

voltage constant)

Delay

between

Modes

(ambient

line

voltage

Channels

At

least10:1

Channel
Dual-trace, alternate

Added

Dual-trace

Channel

1

algebraically

2

up

only

chopped

only

.

.

to50megahertz

between

.

between

.

channels

channels

or

less in

.01

anyone

.

division

.

0.02

division

hour

than

warmup

0

after

one

No

more

picosecondsorless

700

.

.

minute,

per

degreeC.

Specification-7A18/7Al8N

Trigger

Cha,~~o,puo

source

With

Selection

7700

75

MHz

SeHes

TABLE

Performance

Channellonly
Follows

ENVIRONMENTAL

DISPLAY

7A18
FREOUENCY

:7-

.

TABLEA

AND

TABLE

1-1

(cont)

Requirement

MODE

MAINFRAME

RESPONSE

60

MHz

1-2

CHARACTERISTIC

selection

.

With

7400S=,ip

50

MHz

Refer

toWeSpecification

Size

Weight

for

the

associated oscilloscope

Fits

all

2

Pounds

.

TABLE

PHYD!CAL

7000-series

10

Ounces

1-3

plug-in

compartments

(1.4kilograms)

.







7A18/7A18N

General

To

effectively

ties

of the

cribes

front-panel

signal

input

various

measurement

Installation

The

7A18iscalibrated

can

be

installedinany

Series

oscilloscopes,
vertical
and
fully
oscilloscope
at
against

plug-in

lower

rails

insertit.

the

bottom-left corner

the

front

OPERATING

Change

use

instrument

control functions,

connections,

compartments.To

of the

The

when

panel

information,ifany,

the

7A18,

must

and

applications

and

compartment

butisintended

7A18

with

front

willbeflush

the

7A18isfully

of the

.

the

operation

be

known.This section

general

other

subjects

.

ready

for

install,

the oscilloscope tracks

inserted,

7A18

SECTION

affecting

and

information

that

useasreceived.It

of

Tektronix

for

principal

align

with

the front of the

and

willbein

capabili-

pertain

7000-

use

the

upper

the

place

this

des-

and

latch

2

INSTRUCTIONS

section

on

to

in

willbefound

at the rear of the

manual

.

To

remove
inscribed
and

the

slide

the

The
connectors
cable.See

Input

Connector

AC-GND-DC

with

will

7A18

7A18

FRONT

following

of

Fig.2-1

the

7A18,

the unit

out

identification

unlatch.Continue
of the oscilloscope

PANEL

AND

CONNECTORS

descriptions

both

Input Amplifier

.

Provides

channel

Selects

AC-The

naliscoupled
input
is

GND-Grounds

while
for the input
charge
capacitortoprecharge
circuit

input toAC.

pull

CONTROLS

apply

signal

.

signal

AC

while

blocked

maintaining

on

the
"7A18"
pullingonthe

.

to

channels

connection

input

component

the

.

the

signal.Provides

path

for

before

latch

(which

or

"7A18N")

latch

the

controls

when

appli-

to

coupling

to the

DC

amplifier

the

theACcoupling

switching

mode

of the

amplifier

component

input

same

the input

and

the

sig-

load

the

is

to

Fig

.

2-1.Front-panel

.

POSITION

a

IDENTIFY
(7A18

only)

controls

DC-Both

Controls

tioningofthe
Display
POSITION

Deflects
trace
with
with

and

connectors.(7A18shown

AC

and

of

the

signal

are

amplifier input

position of the

Modeiscontrolled

trace

identification.In

readout,

the

word

.

trace

control

about0.2

also

"IDENTIFY"

DC

components

coupled

trace.Posi-

in

the

.

only

division

instruments

replaces

.)

to the

"ADD"

by

CH

readout

.

1

for















Operating

VOLTS/DIV

VARIABLE
(VOL1-S/DIV)

GAIN

DISPLAY

TRIGGER

Instructions-7A18/7A181\1

Adjustment

MODE

SOURCE

Selects
from

stepsina
Provides

calibrated
brated
factor
or

When
pushed
screw-driver
bration

Selects
of

CH

ALT---A

ADD-Algebraically

CHOP---A

CH

Selects
The
triggering
base

CH1-Internaltriggeringsignal

MODE--Internal

calibrated

5

mV/Div

1-2-5

continuously

steps.Extends

rangeto12.5volts/division

more

.

the

in,itbecomesafront-panel
of deflection factor

one

operation

1-A

single-trace

signal

appliedtoChannel1.

dual-trace

signal

appliedtoboth

- T -hechannels
played,
the

end

sweep

.

appliedtothe
input
algebraic
the

CRT.The
switch allows
CH1+
Positionofthe

play

modeiscontrolledbyCH

POSITION

signals
Thetwo
sweepasdeterminedbythe
dicator

2--A

single-trace

signal

appliedtoCH2.

sourceofthe

trigger signals

for the

units

.

obtained
CH1.

matically
MODE

deflection

to5V/Div;ten

sequence

settings

VARIABLE

adjustment

of

:

and

connectors,

sum

CH2or

dual-trace
appliedtoboth

channels

oscilloscope

from

selection.In

between

the

the

following

displayofthe

displayofthe

are

alternately

switching

of each

adds

CH1and

is

displayed
CH2POLARITY
the

displaytobe

CH1-

traceinthis

control

only

displayofthe

time-share

.

displayofthe

trigger

provide

oscilloscope

signal

trigger

follows

factors

.

variable

deflection

control

for

.

channels

occurs

time-base

the

and

.

channels

internal

applied

signal

DISPLAY

ADD

un

cali-

cali-

modes

dis-

at

signals

CH

the

on

CH2.

dis-

the

in-

signal

time-

to

auto-

or

is

.

2

1

.

.

CH

CH2POLARITY

GENERAL

Provides

+

INVERT--A

OPERATINGINFORMATION

Introduction

For

single-trace

amplifier

DISPLAY

1orCH2and
appropriate
operations

Signal

connectingasignaltothe
uator
circuit
conditions

ring,

series
coding
fier

on the

probe

units

Vertical

switchto10
oscilloscope
nel
four
exactly

is

ing

channels

MODE

input.In

usingCH1

Connections

In

general,

probe

under

.

The

Tektronix

was

designed

amplifier

ringonthe

unit

which

CRT

being

without

Gain

check

To

calibrator

being

checked.The

divisions.If

four

engagedbypressing

the

knob

operation,

canbeused

and

TRIGGER

connecting

the

only

probes

offersahigh

testtoperform

to

used.For

readout,

offer

P6053A

specifically

units

equipped with readout.The

probe

automatically

the

actual

see

Check

the

gain of

mV

and

connect40mV,1kHz

to

vertical

not,

divisions

with a

of deflection

in

narrow-blade

CHOP

display

signalisthe

1

andCH2

2---Internal
obtained
CH2.

meansofinverting

2

display

-UP--A

and

either

positive-going

CH

2

the

CRT

the

CH

flects

the

ward

.

eitherofthe

independentlybysetting

the

signaltobe

discussionstofollow,

apply

the

most

inputofthe

input

impedance

very

probe,

for

connectstoa

corrects

deflection

probes

the

Tektronix,

to be

Adjustment

channel,

the

input

deflection

adjust

the

the

GAIN

modes,

algebraic

trigger

from

signal

.

input

connector

display

positive-going

2

input

CRT

SOURCE

equallytoCH2only

convenient

7A18.A

closetonormal

with

its

use

with

circuitinthe

the

readout

factoratthe

used

Inc.catalog

set

connectorofthe

shouldbeexactly

front-panel

.

The

GAIN

control

screwdriver

the

trigger

sumofCH

.

trigger

upward

connector

display

switchestoCH

observedtothe

and

readout

Tektronix

with

the

signal

knob

signal

applied

the

signal

at

deflects

.

signal at

down-

two

identical

single-trace

.

means

10X

atten-

allows

operating

cod~ng

readout

ampli­displayed
tipofthe

amplifier

.

VOLTS/DIV

from

chan-

GAIN

adjustment

and

turn-

(see

Front

to

CH

the

de-

the

of

the

7A-

the

for

2-2

Panel

Controls

and

then counterclockwise,

When

the

GAIN

control

will

changeasthe

knob

with

the

screwdriver

exactly

Input

switches

four

divisions,

Coupling

The

Channel1and Channel

allow

a

choiceofinput

typeofdisplay desired
the

couplingtouse

The

DC

DC

component

AC

signals

probe)

and

these

signals

In

theACcoupling

square

.

coupling

of

the

below

about

waves

are

attenuatedintheACposition

signalisblocked by

coupling

DC

precharge
use
probetothe
coupling

inputofthe
input

inputs

to

VOLTS/DIV

determined by

of

the
tion
switch
calibrated

settings
switch.With
wise
brated

volts/division.By

the
set

position

component

much

feature

this

feature,

first

circuit

capacitortocharge

The

GND

position

amplifier

connectors.However,

are

not grounded,

the

signal

source

and

The

amountofvertical

the

the

probe, the

settingofthe

factors

The

and

input

within the

indicated

apply

(CAL

VARIABLE

between

the

vertical

connector,

only

IN)

the

the

VARIABLE

VOLTS/DIV

deflection factor

rangeofthe

provides
should

.

signal

settingofthe

VARIABLE

when

applyingacalibrated

Connectors).Turn

until

the

GAIN

is

engaged,

knobisturned

until

then

remove

the

.

"Turn

the

the

2

coupling

screwdriver

coupling

and

the

applied

position

signal.It

must

must

30

hertz

with

low-frequency

position,

a

capacitorinthe

the

best

larger

than

be

used with

set

the

couplingtoGND.Connect

and

wait

about

.

Then

provides

without

the

and

the

VARIABLE

deflection

amplitude,

signal will

be

also

(ten

theDCcomponent

input

displayofsignals

theACcomponents.The

largeDCinputs.To

two

set

the

a

ground

externally

signals

same

DC

Controls

produced

the

VOLTS/DIV

control.Calibration

by the

position

control

settingsofthe

the

VARIABLE

.

provides

variable,

calibrated stepsofthe

any

control

set

specific

VARIABLE

fully

to5volts/div

is

extended

deflection factor

control

the

knob

clockwise,

controlisengaged

vertical
the

deflection

GAIN

control

deflectionisset

.

(AC-GND-DC)

methods

.

determine

used

to

display

be

usedtodisplay

hertz

with

a

components

.

of

circuit.The

with

seconds

for

couplingtoAC

referenceatthe

grounding

connectedtothe

loadispresented

by a

signal

attenuation

factor

switch,

deflec-

VOLTS/DIV

controlisin

uncalibrated

VOLTS/DIV

counterclock-

the

uncali-

to at

least12.5

voltage

source

can be

.

The

the

10X

the

AC

the
the

the

and

the

to

as

CH

.

displayed

to

Thisisparticularly
when
POLARITY
the

same
will
positive-going
on
move

DISPLAY

CH1inputortheCH2
switchtothe

signalisalso
desired

the

a

MODE

channel1and
Although

.

CHOP
rates

rates
ceptible

switch
signals,

signal,orfor

channeltooffset

other

is

mode

positionisthe
VOLTS/DIV
VOLTS/DIV
the
CRT
resultant
amplitudeofthe
the
channel1POSITION

Chop Mode.The
MODE
switched
hertz
mode

2

POLARITY

CH2POLARITY

The

waveform

differential

measurements

switch

+UP

position,

polarityasthe

move

the

CRT

waveform

the

CRT

in

inverted

the

trace

down

MODE

For

single-trace

operation,

corresponding

To

displayasignalinone

appliedtothe

channelbysetting

Operating

Switch

of

the

useful

has

two

the displayed

applied

trace

at

form

.

Switch

input

Instructions---7A18/7A18N

switch

may

signal

appliedtotheCH2

in

added

aretobe

positions,

signal

andapositiveDCvoltage

up.In

the

theCH2

and a

apply
and

position:CH1orCH2

channel independently

other

channel,

the

DISPLAY

appropriateCH1orCH2position

Alternate

Mode.The

switch

producesadisplay

ALT

position of

which

channel2with each

the

ALT

mode

can be

usedatall

mode

providesamore

below

about 0.2millisecond/division

alternate

mode

satisfactory

switching

.

Add

Mode.The

can

be

for

common-mode

channel).The

with

resultant

display.In

display

ADD

mode,

switch

between

rate

(controlled

provides

ADD

used to

DC

display

offset

the

DC

overall

both

VOLTS/DIV

deflection

switch

.

However,

switches

are settodifferent

amplitude

this

case,
can be
signal

appliedtoone

positioningofthe

control

CHOP

produces a

channels

by mainframe)

the

best

display

position

the

of the

sum

rejectiontoremoveanundesired

(applyingaDC

component

deflection

switches

factor

if

is

difficulttodetermine

the

voltage

determined

traceiscontrolledbythe

only

.

position of

display

at

approximately a

at

sweep

be

usedtoinvert

the

input

operationofthe

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Instructions--7A18/7A18N

millisecond/divisionorwhenever

phenomena

TRIGGER

CH1.

switch

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applied to the
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.Inthis

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signal
CH1input
signal

CH

connector.This

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signal
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signal

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applied to

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coupling

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in

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near the

.

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IN position

time-base

time-base

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that the

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waveform

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vertically

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move

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procedure

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measurements

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basic

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oscilloscope

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the

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follows

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vertical

values

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voltageis45

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:

signal to

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(see

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VOLTS/D

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:

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volts

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levelata

given

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peak

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setting

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(DC)

input

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7.Measure
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POLARITY
the reference

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Fig.2-3)

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:

Instructions---7A18/7A18N

in

divisions

waveform

.

For

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the

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.6

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a voltage

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VARIABLE

3.To
the
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VOLTS/DIV

Instructions-7A18/7A18N

Measurements

some

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of

VOL-fS/DIV

the

unknown

for

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calibration

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that

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measurements

establishanarbitrary

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produce

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establishanarbitrary

of an

of

the reference

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it

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of
produce
adjustment

unitsofmeasurement

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establish

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sweep

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amplitude.Do

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factor

connector

several

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exact

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switch,

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when

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exact

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cycles

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of

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EXAMPLE
volts,aVOLTS/DIV
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conversion

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five

amplitude

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two

signalsofthe

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measurement

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X

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of 2

signal

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desired

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of

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30

the

be

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make

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6.Measure
calculate
following

2-

6

the

amplitude

vertical

of the

the

setting

conversion

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measure

the reference

the

input

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the

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of the reference

deflection

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VOLTS/DIV

factor

.

reference

=

the

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.

vertical

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of

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and

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connect

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unknown

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and

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or
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culation

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about

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probes

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the

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reference

theCH2

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opposite

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high

.

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time

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low

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frequencies.Set the

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input.Use

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coaxial

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the

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one

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.

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as45°

/division

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sponding

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10.Multiply
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ference

to

.

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on

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Fig.2-4)

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Instructions--7A18/7A181\1

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Measurements

phase

measurements

sweep

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Fig.2-5.High

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7

Operating

Instructions--7A18/7A18N

Common

T-he
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1.Set

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3

the
in

Fig.2-6aline-frequency

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the

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7A18

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.

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line

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frequency

frequency
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signal as

signal
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when

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signal

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maximum

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.

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display

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common-mode

along

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frequency

rejection

rejection.(A)

with

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.

7A18/7A18N

Change

Introduction

This sectionofthe

circuitry
tion
block

circuitisdescribed

the

and
vidual stages

Diagrams
following

relationship

usedinthe

begins

with

diagram

interconnections
the

relationship

.

Complete

schematics

section.Refer

circuit

.

7A18

a discussion of the

shown

in

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of the front-panel

description

BLOCK

The

following

standing
dual
connections
the
represents a
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complete

input

coupling
to the

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Channel2Input Amplifier
in
positioning.The

pull

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circuits

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The

signal

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amount

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amplifier

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Channel

variable gain

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Signal

The

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determined

discussionisprovided

overall

conceptofthe

are discussedindetail.Only

between

diagram

each

to be

major

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1

outputs

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Switches

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circuit

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attenuation

Input

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manual

in
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dual-trace amplifier.The

the

Diagrams

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instrument

section.Then,

block

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circuit

schematics

electrical

DIAGRAM

7A18

the

individual

Diagrams

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.

signal

the

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VOLTS/DIV

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provides

variable gain

of these

Channel

select

DISPLAY

within

on

blocks

section).Each

the

the

schematiconwhich

the

CRT

passes

and

the

through

couplingisselected,

and

the

circuit

trace

signal

circuits

Switches

proper

MODE

affecting

descriptionofthe

descrip-

using the

diagrams

are

to

before

instrument.The

is

switch

signalispassed

positioning.The

polarity

control,

are

signal

and

to

major

circuit

giveninthe

throughout

values

aidinunder-

the

indivi-

the

basic

are

shown

block

applied to the

the input

selects

provides

inversion

and

applied push-

.

and

trigger

TRIGGER

show

inter-

trace

this

each

indi-

the

and

on

the

the

to

gain

section

willbefoundatthe

SOURCE
provided

The
readout
suppliedtothe
polarity,
the
plug-in
traceisdeflected
factor

General

The
and

The
To

detail

AC-GND-DC

Input

AC-coupled,
S100A
showing
this
position
switchisin
directly
the

acitor

passingtothe
path
ground.This
to

disconnect

Resistor
allows
trace

if

the

rearofthis

switches.The

to the oscilloscope

Readout

logic

deflection

VARIABLE

mode.When

readoutisreplacedbythe

DETAILED

Encoding

for the oscilloscope

mainframe

factor,

controlisin

the

about0.3

CIRCUIT

ATTENUATOR

the

CH1and

minimize

Attenuator
7A18

throughout

circuit

deflection factor

CH2Attenuator

duplication,

this

Switch

signals

connected

DC-coupled,

isacam-type

the

operationisgivenonDiagram

chart

input

prevents

and

C10
remains
applied

indicate

shown

to the

signal

connects

R102,

when

(open

the

DC

Input

passes

the

amplifier.The

the input

provides

the

applied

connected

to be

precharged

on

screen

signal

has a high

or

position,

Attenuator

DC

a

signal

via

circuit

readout

the

the

IDENTIFY

division

determines

.

TE

NO

only

discussion

to the input

or

switch;a

the

associated

closed).When

the input

through

component

GND

circuit

ground

signal

across the

in

when

switchingtothe

DC

manual

.

and

trigger

the

Interface

(7A18

readout

system

uncalibrated

outward

word

position),

buttonispressed,

and

"IDENTIFY"

DESCRIPTION

the

circuits

CH

1 is

.

connector

internally

contact-closure

contacts

the

signaliscoupled

stage.In

capacitor

of the

position

of

the

reference

from

the

level

without

the input

AC-GND-DC

GND

.

outputs

Connector

only) provides

system.Data

identifying

symbol

the deflection

input

are

described

disconnected

1.The

the

C10

opens

position so the

and

.

coupling

identical

can

dots

areinthe

AC-GND-DC

AC

position,

.

This

signal

the

amplifier

the

connector

switch,

AC

position

(when

in

chart

from

signal

need

are

.

is

the

the
the

.

be

.

on

cap-

to

.

Circuit

factor to
attenuators
are
and

vide correct input

signal
ferential
diagram
this

stage.R210

the
or

Description--7A18/7A18N

Input

Attenuator

The

effective

determined
S100B.The

sionofCRT

the

hybrid

capacitors.Each

S100B
closure chart
contacts
5
signalisconnected

uators
produce
These
dividers.For
are
is
reactance
frequencies
higher frequencies, the
and

frequencies
input
RC
of
adjustable
high

General

Input

impedance

Dual-diode

isacam-type

areinthe position

mV/Div

For

switch

are

the deflection factor

attenuators

primarily

determined

the

attenuator

In

addition

attenuators

characteristics

the

VOLTS/DIV

frequencies

The

Channel1Input Amplifier

applied to the

(push-pull)

of the

circuitisshown

Source

The

Input

voltage

negative)15volts.Q210B

overall

by

the

basic

deflection

deflection.To

values indicatedonthe front

are

switched

devices

(see

Diagram

position,

directly

positions

switched

and

DC

resistance

by

the

of the capacitorsinthe

that

their

to

within

are

(one

series

capacitortoprovide

andanadjustable

capacitance

INPUT

Channel1Input Amplifier.A

Follower

Source

withalow

limits

the

CR210

swing

at

deflection

setting

factorisfive

into

which

contain

attenuatorisreplaceableasa

switch

1)
shown

input

attenuationisnot

to the input amplifier

above

into

the

are

frequency-compensated

low-frequency

dividers

resistance

effectisnegligible.However,

reactance

becomes

providing

the

output.Fig.3-1

provides

the

primarilyacapacitance

bandwidth

designedtomaintain

megohm

switch.Each

CHANNEL

AMPLIFIER

Channel1input

on

Diagram2in

Follower

impedance

current

circuit

gateof0210A

factor of

of the

increase

the

and

constant

.

VOLTS/DIV

millivolts

the

basic

panel,

circuit.These

the necessary

the

dots

on

indicate

circuit

indicatedonthe front panel

0210A

drivetothe gate of

providesaconstant

when

(openorclosed).In

five

millivolts,

singlyorin

signals,

and

the voltage

ratiointhe

circuitisso

of the capacitors

attenuation

of the

X

20

attenuator

shunt

1

converts

drive

instrument,

pF)

for

correct

capacitor to

the

connector

showsadetailed

the

Diagrams

providesahigh

for the

protection

to

about±(positive

the

7A18

per

deflection

precision

attenuators

resistances

the

contact-

the

associated

used;the

.

the

pairs

the

attenuators

attenuation

circuit.The

highatlow

decreases

divider

the

same

each

contains

attenuation

single-ended

toadif-

schematic

section

following

Q210A

by

limiting

switch,

divi-

unit

the

input

atten-

voltage

at

the

input

setting

pro-

block

input

current

to

at

all

an

at

of

source
the

same

is

circuit

Paraphase

Paraphase
0225-0325,
the single-ended

Diodes

.

0220
±0.6volt.Common-base

isolation
VARIABLE
Amplifierissetinthis
R237A
IN

switchisin
turned
gain

.

Adjustment1R321
the

same

This

position

Second

.

.

.

The
gainofapproximately
TION
circuitry.The
0250-0350
the
Position of
POSITION
drivetoQ250-0350
impedance
change
from
voltage
of the

inserting

junction

the

emitter

This
traces

The
vides
work
stage

Emitter

Emitter
put

Switches,

between

for

0210A.0210A

case so that

.

Cascode

amplifier

formsacascode

CR220-CR221

closetoground

between

controls.The

with

the

fully

counterclockwise

of the

amplifierisreduced

voltage

preventsazero-volt

when

Cascode

Second

control and,inthe

provide

POSITION

the

control,

pointinthe

at

these

the

POSITION

differenceatthe

.

trace

resistor
of

R11-R256.This
current of

in

aids

.

impedance

identifying

are

displayed

network

high

frequency

provide

high-frequency

Follower

Follower

U270-U470.This

the

Second

Amplifier

input

the

CAL
the

outward

varies

levels at

varying

Amplifier

Cascode

emitters of

a

control

traceisdetermined

R11.This

.

points.However,

Trace

R357

.

C246-C345-C245-R246-R345-R245

compensation.R245-C245

stage

to

drive

Cascode

and

Q210B

0210B

low-impedance

Since

temperature-compensates

Q220-0320,

amplifier.022..0-0320

signaltoa
hold

the

voltage

to

limit

connected

paraphase

gain

stagebyfront-panel

IN

switch

(uncalibrated)
to

the base

the

collectorsofQ225

reference

the

GAIN

Amplifier

two.This

7A18

and

IDEN-TIFY

control

the

circuit,

control

collectorstochange
identificationisaccomplished
from

ground

results

Q250

to

the

channel1trace

response

Q260-0360

the

Signal

stage

Amplifier

are

encapsulated

in

conjunction

differential

the

voltage

amplifier

of the

pressedin.

minimum

byafactorofat

levelof0320

trace

or

VARIABLE

stage

stage

only,

common-base

point

by

emitters

thereisnegligible

the

produces

through

in a

cause

and

also

output

levelatthe base of

swingtoabout

0225-0325

and

the

Channel

GAIN

When

position

resistance,

from

providesasignal

includes

trace

IDENTIFY

for

injection

switch

the

setting

changes

the

adjustment

providesalow

and

the current

areavery

change

resultant

a

the position

CR357

slight

tracetomove

when

Trigger

provides

U270-U470

increase

to

and

the

connected

in

in

the

with

convert

signal

provide

GAIN-

1

Input

control

the

CAL

and

the

least2.5

provide

0325
changing
controls

POSI-

of

currents

of the

low­voltage
current

DC

by

to the

multiple

pro-

this

net-

for

this

out-

Channel

isolation

.

in

.

.

.

.

.

in

.

Circuit

Description-7A18/7A181\1

2

PARAPHASE

AMPLIFIER

INPUT

INPUT

SOURCE

FOLLOWER

CHANNEL

General

The

Channel

same

as

the

differences
Portionsofthis
cription

Input

operateinthe

Amplifier

assignedinthe

2 Input

Channel1Input Amplifier

between

circuit

circuit

400--599
block diagram of the Channel 2
schematicofthis
Diagrams

section

.

Amplifier

the

two

not

describedinthe

same

(corresponding

range).Fig.3-2

circuitisshown

CASCODE

Fig

.

3-1.Channel1Input

AMPLIFIER

circuitisbasically

circuit.Only

circuits

mannerasfor the

Input

are

described

following

circuit

showsadetailed

Amplifier

on

Diagram3in

here

Channel

numbers

circuit.A

the
the

des-

1

the

Amplifier

.

detailed

Paraphase

The

Paraphase

of

Q420,

to

the

functions described

fier,

the

block

Cascode

0520,

Channel 2

providesameansofinverting

CH2POLARITY

biasedonand
Amplifier
the

0525
provide

CH

are

stageasfor

2

POLARITY

biased

signal

inversion

EMITTER

FOLLOWER

L,

.~ .

.

CHANNEL

diagram

.

Amplifier

Cascode

Q425,

switch

the

signalispassedtothe

off

Amplifier

0525,

under

Paraphase

for

Q426,

and

Channel1Input

Cascode

Channel2consists

Q526

the displayed

setto+UP,

Q425

the Channel1InputAmplifier.With

switch

and

settoINVERT,

Q426-0526

are turned

.

TO

TRIGGER

SWITCH

U470

1126-08

.Inaddition

Amplifier

signal.With

and

0525

Second

Q425

Ampli-

stage

the

are

Cascode

and

on

to

PARAPHASE

INPUT

SOURCE

FOLLOWER

FROM

INPUT

ATTEN

REV.D,

Q41
0410B

DC

BAL

DEC.1976

OA

CASCODE

AMPLIFIER

0420
0520

Q426

0425

0526

0525

CH2POLARITY

GAIN

AND
VARIABLE
CONTROLS

AL

IN

Fig.3-2.Channel2Input

-I

IDENTIFY

FROM

(7A18

Amplifier

SECOND

CASCODE

AMPLIFIER

0440
0540 0460

0450

0550

w

S23

only)

detailed

block

EMITTER

FOLLOWER

0560

diagram

TO

SIGNAL

CHANNEL

SWITCH

U270

TO
TRIGGER
CHANNEL

SWITCH

U470

.

3-3

Circuit

Description-

7A18OA18N

Second

0440,
by

as
PLAY

applied to the

1932.The
emitters of
impedance
change
from
voltage
of the
ADD
tors

to

volts

Since
the

control

Cascode

The

Second

0540,Q450,

the

POSITION

determinedby

MODE

switch position

center

POSITION

Q450-0550.Since

pointinthe

at these

the

POSITION

differenceatthe

trace.When

position,

19455-19555

the

emitters of

(approximately)

+50

voltsisnot applied to the

ADD

position of the

setting

Cascode

points.However,

+50

through

hasnoeffectonthe

CHANNEL

General

The

Channel

outputs

to the
determined by
SOURCE

Diagram4in

Signal

circuit

The

Channel

Signal

U270

one,ormixes
from

the

Switch

stage

vides the

DISPLAY
19376-19377

Switches

oscilloscope

the

switches.A

the

Diagrams

Switch

Channel

and

its

two

DISPLAY

determines

signal

to the oscilloscope

MODE

set

the
C274-19274-C275-19275
vide

high-frequency

and

C375

in

these

sation

adjustments

Fig.3-3
position of
pin 14isLO
at

pin 4.With

LO,
passed
only
this

operating

of

channel1and

determines

the

when

the

signals

to the

the

the

shows

DISPLAY

the

outputofU270isdetermined

the

from

Signal

DISPLAY

mode

channel2signals

mainframe

Amplifier

and

control,

the

DISPLAY

Amplifier

0550.Position of

for

R21orby

MODE

other

arm

of the

POSITION

control

varies

the

the emitters areavery low-

circuit,

control

thereisnegligible

produces

collectorstochange

the

DISPLAY

MODE

voltsisappliedtothe

R32

to

balance

0450-0550.This

difference

between

DISPLAY

circuit

SWITCHES

circuit

provides

via

the

DISPLAY

schematic

Switch

external

input

analog

MODE

which

switch

setting

current

and

compensation

networks

section

MODE

of
.

stage

components.This

signalsinresponse

switch.The

input

.

Resistors

gain

for

each

C374-19374-C375-19375

for

are

high-frequency

.

the

U270

input

combinations

MODE

switch.When

levelatpin14HI

both

channel1and

Output

the

MODE

signal

stage.This

switchissettoADD.In

outputisthe

and

deflection

.

Channel2consists

the

traceisset

network

switch.In

than

current

ADD,

control

19455-8555

any

DIS-

I-50

volts

through

drive

to the

voltage

the

change

a

resultant

the

in

current

position

switchisin

junctionofresis-

the

results

in a

POSITION

MODE

operation

Signal

Interface

and

this

circuitisgiven

current

the

Connector

drive
fixed
collectors

control

switch,

.

and

Trigger

TRIGGER

zero

consistsofintegrated

stage

selects

to inputs

Signal

Channel
(CH1or
as

CH

controlled

2)

pro-

by

19276-19277

channel.Networks

pro-

each

channel.C275

compen-

for

each

the

level

by

the

level

and

the

levelatpin 4

channel2are

condition

the

resultant

algebraic

occurs

sum

signal

DC

the

the

the

and

of

is

SELECTED

CH

1

ALT

---~

CHOP

*Levelisswitched
mate0.5

**Levelisswitched
determinedbythe

Fig.3-3.U270

megahertz

input

between

settingofthe

rate

.

between

combinations

the

HI-level

the

HI-level

time-base

for

and

unit

DISPLAY

LO-levelatan

and

LO-levelata

sweep

rate

MODE

approxi-

.

selection

rate

.

.

in

-

Trigger

Signal

(CH1or
triggering
signaliscontrolledbyinputs
switch.Resistors

rentgain

as

C474-19474-C475-19475
vide

Channel

The

Trigger

Channel

CH

of the

high-frequency

Switching

Channel

Switch

Switch.This

2)

provides

time-base

19476-19477

for

each

and

compensation

U470

is

stage

determines

the

trigger

unit.The

from

and

signal

selection

the

TRIGGERSOURCE

19576-19577

channel

C574-19574-C575-19575

for

each

channel

identical

which

for

of the

set

.

Networks

to the

input

internal

trigger

the

cur-

pro-

.

on

An

input/output

When

the

levelatpin
determinedby
and

the

levelatpin4LO,

triggers

Signal

Output

-

The

are

and

Signal

stage,

added

Trigger

ofapairofcommon-base
vide the

circuits

at

General

mines
the
by

This

mainframe
mation

The

Signal

the

circuit

DC

.

Display

which

DISPLAY

for

level

input

andT-

also
chop
proper

table

the

levelatpin4.

algebraically

Output

Output

0480-0580,

shifting

DISPLAY

TRIGGER

Mode

signal

rigger

MODE

provides

blanking

CRT

for

this

stageisshown

14isLO,

With

the

channel1and

.

stage,

Q280-0380,

are

similar.Each

connected

necessarytodrive

MODE
SWITCHING

and

Trigger

(Channel1or

outputs

and

plug-in

circuit,

display

to the

TRIGGER

mode

and

.

the

output

the

level

at pin14HI

and

the Trigger

stage

transistors

the

AND

Switching

circuit

Channel2)provides

mainframe

SOURCE
information

readout

control

in

Fig.3-4

of

U470

channel

consists

which

mainframe

deter-

as

selected

switches

to

infor-

.

is

2

pro-

.

the

Circuit

Description-7A18/7A18N

DISPLAY

The
to the
Switches
position of the

3-3

.

"

TRIGGER

The
puts
Switches
positionisshown

Fig.3-4.Input/Outpu
TRIGGER

MODE

DISPLAY

Signal

diagram

SOURCE

TRIGGER

to

the Trigger

diagram4).Atable

SOURCE

CONNECTORS

General

The

Connectors

power
Connector

of this
section

supply

.

and

and

the

circuitisshown

Connectors

All

the

connections

are

shown

on

the

shown

are

the

power

Switch

MODE

Channel

4).A

DISPLAY

SOURCE

in

Fig.3-4

t

switch

and

signal

Readout

Connectors

supply

switch provides

Switch
table

MODE

Switch

switch

Channel

of the

.

combinations

selections

AND

Readout

distribution

Encoding

on

Diagram

made

to

decoupling

stage

of

the

switchisshown

provides

Switch (U470,

outputs

for

DISPLAY

.

READOUT

circuit

from

circuit.A

6inthe

the

mainframe

portion

of

components

logic

level

(U270,

outputs

logic

for

each

MODE

consists

the

schematic

by

Diagram6.

outputs

Channel

for

each

in

level

out-

Channel

switch

of the

Interface

Diagrams

the

7A18

Also

.

Fig

and

Readout

1 -heReadout
resistors
the

.

Channel
readout
(VARIABLE)
only).Dataisencoded
resistors

adding

current

R647-CR647

(TS-3)

and

in

the

uncal

than)

being
out.R648
the

Column

is in

the

(inverted)

readout

VOLTS/DIV
VOLTS/DIV
contact-closure chart
associated
select

combination

prefix

through
switch.R638
positions.R630,
stage
again
the

factor
sensing
sink
this

clude

input

stage
only

used
voltage
supply.The
determines,
current.When

Interface
collector
through

.

Switching

the

and

(Q620)

depending

VOLTS/DIV

Probe

of the

through

circuit

the

connector

from

;

see

for

divider

Encoding

Encoding

and

probe

sensing

1

and2,Row

of deflection

information,

between

INVERT

.5

sensing

the

probe

Operating

the

Connector

currentisadded

Interface

them

through

are

Column

position.This

displayed

(Channel

output

position.-

being

displayed

resistors
switch

switchisa

contacts
number

that

is

R639

selects

V

(500

selects

R631,

select

on

switch

stage

probe

amount

the

probe

corrects the

attenuation

provides

the

probe

IDENTIFY

with

resultant

along

with

the

Connector

output

line

1,2,or 5

switchedin.

the

Instructions).The

-15

(7A18

factor,

switched

preceding

2 only)isswitched

are

to the

(see

are

mV)

the

the

connected

of

R621

voltage

B33,

only)

circuit

stage

Q620.This

and

Column

uncalibrated

and

signal

on

these

output

and

the

time-slot

0620

.

between

line

when

resultsinthe

the deflection factor

when

theCH2

This

resultsinthe

preceding

usedtoindicate

mainframe

cam-type

closed.R633,

the

symbol

and

decimal

resistor

.

Q620

current flowing

coding

mainframe

the

coding

input.The coding

through

emitter

volt

switch.The

Diagram

depending

R637

symbol

positions of the

V

the

output

point

combination

identifies

to the

resistance.The

factor

.

The

input

resistance

CR621

sets

the

resistor

time-slot

Q620

is

to

the

column

A37

.

consists

the

the

6)

V

in

readout

to the

third

interrogated

of

circuit

output

deflection factor

inversion

linesbyswitching

between

POLARITY

readout

indicate

selects

(volts)inthe5mV

the1,2,

of the

(number

input

third

biasonQ620

R622,

pulseisapplied

(channel

input

lines,orby

time-slot

CAL

IN switch

symbol>(greater

symbol

deflection

the

setting

system.I-he
dotsonthe

when

R634,

and

on

the

them(milli-)

VOLTS/DIV

probe

of

switchedinby

the

attenuation

connector

from

the

output

system

contact

probe

(coded

contact

resistor

to the

the

current

switching

encodes

lines

for

three

read-

TS-2

and

switch

factor

of the

the

R635

resistor

and5V

sensing
zeroes)

by

current

of

to

in-

of the

sensing

probes

is

also

forms

--15
and

collector

to

and

its

output

2

is

I

a

V

REV.D,

JAN.1975

3-

5

Circuit

Description-7A18/7A18N

Witha1X
connector,
outisdeterminedby
a

10X

probe
microamperes
the deflection factor

The

two

things

1.It
channel
discussiononthe

0620

IDENTIFY

when

causes

of the

probe

connected,

of

pressed

7A18

(or

no

is

turned

the

VOLTS/DIV

the

collector

readoutbya

button

the

Channel1or

:

trace
to

move

(S13orS23

probe)

connected

off

.

The

deflection factor

switch

position.With

biasonQ620

currenttoflow.This

factor

representing

about

Channel2Input

will

of 10

.

on

Diagram1)does

the

0.3division

to

the input

read-

allow

increases

appropriate

(see

Amplifier)

100

the

2
sufficient
to

the

readout

These
when
buttonisreleased,
position

For

.

system,

.

Forward

column

with

multiple

are

further

see the

biases

amount

current output,

the

word

two

actions

traces

restored

information

oscilloscope

CR621

of

collector

"IDENTIFY"

aidinidentifying

are displayed.When

the

deflection factor

.

and

current

replaces

on

the

instruction

Q620

which,

the

.

readout

operation

manual

to

result

when

deflection

the

7A18

the

IDENTIFY

and

of the

.

in a
added
factor

trace

trace

readout

7A18/7A18N

Change

information,ifany,

Introduction

This

sectionofthe
mation
tenance,

for useinpreventive

and

Further

color

codes

instruction

troubleshootingofthe

maintenance

and

manuals

manual

information

soldering

for

the

techniques

7000-series oscilloscopes

PREVENTIVE

General

Preventive

inspection,

will

improve

maintenance,

lubrication,

the

reliabilityofthis

etc.,performed

checks on the semiconductor

not

recommended

See

semiconductor-checking

Troubleshooting

asapreventive

.

contains

maintenance,

7A18

relatingtocomponent

can be

MAINTENANCE

consisting of

instrument.Periodic

devices

used

maintenance

information

affecting

maintenance

corrective

.

foundinthe

cleaning,

onaregular

in

the

measure

given

.

unit

under

this

infor-

main-

visual

basis,

are

section

will

Lubrication

Useacleaning-type

connecting

switch
containing
tionsisavailable
Tektronix

Recalibration

To

checked

months
check

The

isolating
troubles
revealed

.

befound

at the

rearofthis

lubricant

plug

contacts,

detents

withaheavier

the necessary

lubricating

through any

Part

Number

ensure

accurate

after

each

if

used infrequently.A

003-0342-01

measurements,

1000

hours

procedureisgiveninPart

performance

major

not apparent

and

corrected

check procedure can

troublesinthe

during

.

TROUBLESHOOTING

manual

and

switch

grease.A

Tektronix

of

I

for

regular

.

on

shaft

bushings,

contacts.Lubricate

lubrication

materials

Field

and

Office

.

the

7A18

operationorevery

complete

performance

Section5.

be

helpful

unit.Moreover,

operation

instruc-

.

Order

should

minor

may

inter-

kit

be

six

in

be

Cleaning

Avoid

cloth
used;however,

the

use

might

damage
chemicals containing
tone,orsimilar

Front

Panel.Loose

oradry

abrasive cleaners

Interior.Cleaning

cede

calibration,
settingsofthe
compressed
dirt

can be

swab,
solution

or

.

airtoblow

removed

cloth

of

chemical

the

plastics

benzene,

solvents

dust

brush.Water

the

since

the

calibration

off

with a

dampened

cleaning

in this

instrument.Avoid

toluene,

.

may

be

removed

and

mild

should

interiorofthe

cleaning

process

adjustments.Use

the

accumulated

soft,

dry

brush,

with a

mild

agents

xylene,

detergent

not be

used

unit

could

dust.Hardened

cotton-tipped

detergent

which

ace-

withasoft

may

be

.

should

alter

pre-

the

low-velocity

and

water

General

The

followingisprovided
containedinother
shooting
Description,

advantage

information

.

the

and

'The

on

7A18.The

Circuit

circuit

Troubleshooting

Diagrams.Circuit

Section7.
component

Important

Circuit

The

circuit

in

this

voltages

Board
outlinedonthe
the

board

is

shown

board-mounted

electrical

photographbyits

sections of

Calibration

Description

behavior

Aids

diagrams

number

instrument

are

also

.

The

circuit

schematic

on

the

component

circuit

number

to

this

schematic

sections

and

are

given

and

are

shown

.

board

diagrams,

back

.

augment

manual

information

when

diagrams,

trouble-

Circuit

shouldbeusedtofull

section

output

electrical

shown

gives
requirements

on

foldout

valueofeach

on

the

usedinthe

detailed

pages

diagrams

7A18

andaphotograph

of

Diagram1.

is

identifiedonthe

.

in

.

is

of

Each

Maintenance---7A18/7A18N

not

and

color

coded

Wiring

and

wires

capacitors

coded

to

Component

dots

on
tolerances,
Components
on

the

body

The

insulated

7A18

are

resistors

etc.,according

.

color

pointtoanotherinthe unit

Lead

Semiconductor

lead

configuration

instrument

.

Troubleshooting

The

following

the

7A18

.

1.Semiconductor

transistors,

diodes,

helpful.A

Type

576

will

transistor-curve tracer

give

Configuration.Fig.4-1

of the

Equipment

equipment

Tester---Some

and

the

most

Color

Code.Colored

signify

to the

EIA

usually

used

for

interconnection

facilitate

tracingawire

.

semiconductor

is

useful for

FET's

used

complete

electrical

standard

have

the value printed

devices

troubleshooting

means

in

this

such

as

information

stripes

color

from

shows

used

of

testing

instrument

the

Tektronix

.

or

values,

code

in

the

one

the

in this

the

and

an

.

circuit

equipped

unit

and

3

.

.

that

does

function

connector,

voltmeter

ohmmeter

required

is

.

unit,

witha10X

before

settingofthe

not

2.DC

checking

.

checking

3.Test

view

A
readout
Time-Base
probe

Troubleshooting

This
which
ceeding

1.Check

7A18
there

is

tion
Operating

Voltmeter

voltages

resistors

Oscilloscope--A

waveforms

Tektronix

system,

unit,

will

meet

troubleshooting

checks

with

extensive

Control

controls

question

is

any

a

control

of

Instructions

and

within

the

and

diodes

at

different

7000-series

7D13

Digital

anda7A-series

the

needs

for items

Procedure

procedureisarrangedinan

simple

the

troubleshooting

Setting.An

indicateatrouble

can

about

or

front-panel

section

Ohmmeter--A

circuit

are required

test

oscilloscope

pointsinthe

Oscilloscope

Multimeter
Amplifier

2

trouble

possibilities

incorrect

the correct

.

for
for

with

7B-series

order

pro-

exist.If

or opera-

see

the

to

a

Fig

.

.

Electrode

4-1

4-2

configuration

for

semiconductors

used

in this

instrument

.

Maintenance-7A18/7A181\1

2.Check

Associated

Equipment
with troubleshootingofthe
ment

used with

possible,

substituteanamplifier

correctly
persists.Check
that

the interconnecting

3.Visual

instrumentinwhich

can

be

locatedbyvisual
connections,
damaged

components,

4.Check
brationofthe
PartI-­trouble
corrected
are

5

given

.

Check

Performance

may

by

in

component
correct voltage
and waveforms
are

not

absolute
ments.To
to

take

these

section

.

6.Check

methods

are

nentsinthe
are

best

checked

measurement

A.TRANSISTORS

The

best
operationisactual
Ifatransistororintegrated

defective,itcan

ponent

known
conditions
damaged.If

dynamic
testers
under

tester

maybeused,

simulated operating conditions
unnoticed.Fig.4-1
of

semiconductor

this

instrument

into

the

indicator

that

the inputs

cables

Check.Visually

the

troubleissuspected

broken

etc

wires,
.

Instrument

unit,orthe

CheckofSection5.

only

be a

resultofmisadjustment

calibration.Complete

Part

I IofSection5.

Voltages

or

obtain

readings,

and

stage

can be

or

waveforminthe

are

givenonthe

and

may

operating

see

Individual

provided

7A18

from

for

.

Components

by

disconnecting

the

effectsofsurrounding

AND

check

of

transistor

performance

best be

tobegood;however,

are

not

such

thatareplacement

substitute

transistors

(suchasTektronix

but

since

shows

base

devices.Be

indications,

Performance.Check

affected

Waveforms

vary

conditions

the

Components.The

checking

circuit

checked

attemptingtoremoveorreplace
circuit

.

.

Before

7A18,

check

that

is

operating

unit

known

to

unit

and

seeifthe

are

are

not

check

damaged

properly

connected

defective

the

portionofthe

.

Many

such

as

circuit

circuitbyperforming

The

calibration

.

Often the

located

by

checking

circuit.Typical

diagrams;however,

slightly

between

similartothose

instructionsinthe

the

individual

which

are

solderedinplace

one endtoisolate

circuitry

INTEGRATED

and

integrated

under

operating

is

suspectedofbeing

by

substitutingacom­be sure

might

are

not

available,

Type

576).Static-type

they

do not

check

some

defects

pin

and

socket

arrangements

sure

the

power

is

any

transistororintegrated

proceeding

the

equip-

correctly.If

be

operating

problem

and

.

troubles

unsoldered

boards,

the

cali-

apparent

and

may

be

instructions

defective

for the

voltages

these

instru-

used

Diagrams

following

compo-

the

.

CIRCUITS

circuit

conditions

that

circuit

also

be

use

.

a

operation

may

go

off before

Integrated

circuits
oscilloscope,orby
standingofthe
shooting
checking
circuits

so that
integrated-circuit
clippingatest

cuits.This

extraction tool

B.DIODES.A

a

short

circuitbymeasuring

nals

withanohmmeter
resistance
when

the

diodes

or

Do

not

current.High

circuit

circuits

using

voltages

adjacent

test clip

probetothe 14-

device

.

should

be very highinone

meter

leads

back

diodes

use

an

ohmmeter

currents

and waveforms

diode

C.RESISTORS.Check

Resistor
Resistors

measured

toleranceisgiven

normallydonot

value

varies

D.CAPACITORS

detectedbychecking

.

highest
voltage
should
capacitor

by

required
Component
manceofany

any
affected

scale.Use

rating

be high

can

checking

7.Repair
to

electrical

circuit

an

of

the capacitor.The

after

initial

bestbedetected

whether

and

Readjust

replace

components

Replacement.Be

circuit

components

may

be

REPLACEMENT

Standard

All

7A18
Officeorrepresentative.However,
electronic
thanisrequired to
purchasingorordering
lists

Parts

electrical

canbeobtained

components

for

value,

tolerance,

and

order

can be

checked

direct

substitution.A

description

integrated

withavoltmeter,

is

essentialtotrouble-

circuits.Use

around

leads

are

not

shorted

provides

also

doublesasan

a

and

convenient
16-pin

canbechecked

the

resistance

the

set

to

RX1kscale.The

direction

are

reversed.Do

withanohmmeter

scale

that

hasahigh

may

widely

damage

resistors

in

need

from

the

to be

the

the

with

Electrical

replaced

specified

.Aleakyorshorted

resistance

ohmmeter

withanohmmeter

which

will

chargeofthe capacitor.An

withacapacitance

the capacitor

passesACsignals

the

Circuit

in this

.

unit

sure to

that

has been

repaired

replaced.Recalibration

necessary

.

PARTS

mechanical

through your

canbeobtained

them from

replacement

rating,

part

many
Tektronix,

parts,

and

description

replacements

local

locallyinless

good

under-

care

when

the

integrated

together.An

means

integrated

integrated-circuit

foranopenorfor

between

termi-

diode

very

and

not

check

tunnel

.

internal

diodes

.

an

ohmmeter
Parts

List

unless

value

.

capacitor

can
on

not

exceed

resistance

reading

open

meter,

.

Special

check

techniques

are

given

the

or

that

Tektronix

of

the

standard

under

perfor-

has had

of

the

for

the

Field

time

Inc.Before

check

the

parts

.

test

of

cir-

low

.
.

the

be
the
the

or

REV.D,

MAY,

1975

4-

3

Maintenance-7A1

8/7A18N

When

selecting
remember
component
ment.All
ments

unless

will

not

adversely

Special

to
Tektronix

indicatedinthe
number.Most
ment
special
Officeorrepresentative

Ordering

refertothe
and
trical

circuit

Soldering

boards
excellent
care

rules

Parts

Some

parts

satisfy

particular

to

have

parts

Parts

When

ordering

Symbols

Parts

1.Instrument

2.Instrument

A

description of the

3

.

number)

4.Tektronix

Attenuator

are

electrical

when

cleaning or

shouldbeobserved

1.Useavery

replacement

that the

may

affect

replacement

it is

are

manufactured

our

specifications.These

parts

of the

been

manufactured

directly

replacement

Parts

Ordering

on

the

List

section.Include

type

Serial

Part

Techniques

Circuit

made

from

characteristics.Use

small

requirements,orare

NOTE

physical

its

parts

known

that a

affect the

listbyan

mechanical

from

.

Information

page

immediately

(7A18)

Number

part

Number

Boards.The

polyphenylene

soldering

when

soldering

parts,

it is

important

size

and

shape

performance

shouldbe

different

instrument

or

asterisk

parts

by

your

parts

the

(if

this

removingorreplacing

iron

in

the

direct

component

performance

selectedbyTektronix

manufactured

special

preceding

usedinthis

Tektronix.Order

local

Tektronix

from

Tektronix,

and

Special

preceding

following

electrical,

oxide

material.The

(not

information

Attenuator

becauseofits

more

than

over15watts)

to

of

the

instru-

replace-

.

for

parts are

the

part

instru-

Field

Inc

Notes

the

Elec-

include the

circuit

normal

following

parts

.

all

General

The

ical

assembling

Circuit

In

never
connections

nections.If it is
assembly,

A.READOUT

1.Disconnect

board

.,

:

:

2

mounting

3.Disconnect

board

4.Remove

5.To

ATTENUATOR

B

.

1 .

procedure

2.Disconnect

rear

3.Loosen

control

4.Remove

from

COMPONENT

exploded-view

Parts

List

individual

Board

general,

removed

be

use the

.

.

Remove

surface

.

replace

Remove

.

of the

board

shaft

the control

may

Removal

the

to the

following

CIRCUIT

the

the

.

the wires

the

board

the

the

readout

the

.

the

front

coupling

the red

shaft

REPLACEMENT

drawing

be

helpful

components

circuit

unless

seven

CIRCUIT

boards

they

boards

necessary

wires

board,

.

are

procedures

BOARDREMOVAL

connected

screws

connected

from

the unit

reverse

BOARD

boardasoutlinedinthe previous

resistor/capacitor

set

screwonthe

(usea0

VARIABLE

associated

when

or

must

made

to

holding

.050-inch

with

disassembling

sub-assemblies

usedinthe

replaced.Electrical

be

by

replaceacircuit

.

to

the

the

to the

.

the

orderofremoval

REMOVAL

connected

VARIABLE/GAIN

hex-key

control

the

Mechan-

or

.

7A18

need

soldered con-

board

(7A18

only)

outsideofthe

board

to the

inside

of the

.

to the

wrench)

knob

and

rod

re-

.

2.Do

not

apply

more

heat,orapply

time,

thanisabsolutely

3.Useavacuum-type

excess

solder

from

4.Do

not

apply

or

halogenated

5.To

methyl,

hydrocarbons

clean,

or isopropyl alcohol

use

the

any

necessary

circuit

solvent

only

.

desoldering

board

.

containing

.

water-soluble

.

heat

for

a longer

tooltoremove

ketones,

detergents,

the

esters,

ethyl,

5.Remove

1/16-inch

6.Remove

7.Remove

8.Disconnect

connector

9.Remove

the remaining

hex-key

the front panel

the

the

.

the

wrench

.

attenuator

wires

input

BNC

from

shields

and

resistor

connector

front-panel

the

instrument

.

from

.

knobs

the input

using

.

a

BNC

Maintenance--7A18/7A18N

10.Remove

nut

driver

11.Remove

the

instrument

12.To

.

.

replace

the

POSITION

the

attenuator

the board,

C.AMPLIFIERCIRCUIT

1.Remove

viously

.

2.Remove

instrument

3.Disconnect

the

front-panel

4.Loosen

coupling

0

.050-inch

shaft

from

5.Loosen

between

switch

long

sections.Pull

shaft

the

.

controls

the

of

hex-key

the

frontofthe
the

the

DISPLAY

from

the

Readout

plastic

the

front hex-socket

the

wrench

front

the

frontofthe

reverse

BOARD

circuit

plug-in

wires

connectedtothe

.

VARIABLE

.

Pull

instrument

hex-socket

MODE

the-TRIGGER

control usinga5/16-inch

board

with

cam

switch

from

the

order

of removal

REMOVAL

boardsasgiven

guide

from

the

rearofthe

board

screw

in

the

control

the

VARIABLE

shaft

using

knob

.

screwinthe

and

TRIGGER

SOURCE

instrument

.

coupling

SOUCE

knob

.

pre-

from

front

and

and

B.ROTARY

Single
SOURCE
these

SWITCHES

wafers on

switches

switchesisdefective,
shouldbereplaced.A
your

a

Tektronix

When
type

rotary

beyond

solder

Transistor

Transistors

they

are

during

routine

Field

disconnectingorconnecting

switch,donot

the

rivetonthe

can

destroy

and

and

actually

maintenance,
sockets.Special
leads,

because they can

from

sockets.Unnecessary

components

may
Whenatransistorisreplaced,
part of

the

instrument

the

DISPLAY

are

not

new

Office

the spring

Integrated

IC's

should

defective.If

care

must

affect

the

that

MODE

normally

switch

the

replaced.If

entire

switch

can be

ordered

.

leadstoa

let

solder

flow

switch

terminal.Excessive

tensionofthe

Circuit

return

be

Replacement

not

be replaced

removed

them

from

to

giventointegrated

easilybedamaged

replacement

or

calibrationofthe

check

the

operation

may

be affected

.

and

TRIGGER

any

around

contact

their

their

in

switching

instrument

part

assembly

through

wafer-

and

.

unless

sockets

original

circuit

removal

of that

of

of

.

6.Loosen

the

DISPLAY

key

wrench.Pull

from

the

7

.

connected

8.Remove

the

chassisorother

9.Remove

10.To

Switch

Several
following
the cam-type

the

front

MODE

the

frontofthe

Disconnect

to

the

ceramic

the

screws
mounting

the board

replace, reverse

Replacement

typesofswitches

special

maintenance

switches

A.CAM-TYPESWITCHES

Repairofcam-type
onlybyexperienced
alignment
carefully

switch.For

switches,

representative

and

spring

maintained

assistance

contact

.

your

her-socket

switch
DISPLAY
instrument

the

shaft

MODE

.

resistor-capacitor

stripsatthe

and

nuts securing

surface

from

the

the

orderofremoval

are

informationisprovided

and

rotary

switches

switches

should
maintenance
tensionofthe

for

proper

in

maintenanceofthe

local

Tektronix

screwinthe

coupling

usinga5/16-inch

knob

and

combinations

frontofthe board

the board

.

instrument

.

.

usedinthe

.

be undertaken

personnel.Switch

contacts

operationofthe

cam-type

Field

Office

hex-

long

shaft

.

7A18.The

for

must

be

or

to

of

Recalibration

After

any

After

electrical
calibrationofthat
wellasthe
Performance

provide

calibrationofother

Check

a quick

and
instrument operation
of

Section5can

meet

the

Performance

Repackaging
If

the

Tektronix

Service

owner
firm

number
Save

Center

(with address)

that

andadescriptionofthe

and

re-use
shipped.If
available,

repackage

Surround
protect

corrugated

having

than

the

by

tightly

foam

between

carton

The

carton

the

inside

with

thenbeused

for

instrumentisto be

for

can be

the

the

original

the

instrument

finishofthe

cardboardofthe

dimensionsofno

instrument

packing

carton

shipping

test

strength

Repair

component

particular

circuit

closely

instructions

convenient

. -

The

giveninPartIof

means

Calibration

to adjust

Requirements

Shipment

serviceorrepair,

and

the

nameofan

contacted,

complete

service

packageinwhich

packagingisunfit

the

instrumentasfollows

with

polyethylene

instrument.Obtain a

correct

less

dimensions.Cushion

three

inches of

and

instrument,onall

tape or

for

industrial

your

instrumentis200

has

been

replaced,

shouldbechecked,

related

circuits.The

Section

of

checking

Procedure

in

Part

the operation

listedinSection1.

shippedtoa

attachatag

Tektronix

showing

individualatyour

instrument

required

your

.

instrument

for

useornot

:

sheeting to

carton

carton

strength

than

six

inches

the

instrument

dunnageorurethane

sides.Seal

stapler

pounds

the

as

5

the

I

I

to

:

serial

was

of

and

more

.

REV.E

DEC

1976

4-5

7A18/7A18N

Change

Recalibration

To

assure

the

7A18
months
thoroughly
the

if

Maintenance

Tektronix

Tektronix,
recalibrationatlocal
Service
or

Center.Contact

representative

Using-This

General.This
tate

checkingoradjusting

Index.To

Check
ceding
ment

or
PartI---

procedure

Interval

instrument

every

used

infrequently.Before

clean

and

section

Field

Inc.provides

for further

Procedure

section

aid

Adjustment

Performance

.

information,ifany,

1000

accuracy,
hours

inspect

.

check

of operation, or every

this

instrumentasoutlined

Service

complete

Field

Service

your

local

information

provides

the

in

locatingastepinthe

procedure,

several

7A18.These

Check

the

complete

instrument

Centers

Yektronix

.

features to

are

an

indexisgiven

and

PartII--

affecting

calibration

calibration,

repair

and

the

Field

:

Performance

this

and

Factory

Office

facili-

pre-

Adjust-

of

six

in

section

willbefound

instrument

within

General

The

equivalent,

7A18.Specifications

minimum
some

of

precise
equipment.All
calibrated

The

based

on

is

substituted,

need

tobealteredtomeet

ment

used.Detailed
equipment
instruction
mationisneeded

at

is

all

Performance

TEST

following

is

necessary

the

specifications

than

the

and

operating

Performance

this

recommended

are

manual

the

rearofthe

both

EQUIPMENT

test

required

given for the
for

actual

test

equipment

Check

control

not

giveninthis

for

.

manual

.

correctly

Requirements

adjusted

as

REQUIRED

equipment

for

accurate

listed

performance

within

and

equipment.If

settingsorcalibration

the

operating

the

and

complete

test

calibration.Therefore,

here

may

capabilities

is

assumed

the

listed

Adjustment

requirements

instructions

procedure.Refer

test

equipment

calibration

equipment

and

performing

given

in

Section1.

accessories,orits

of

the

are

the

be

somewhat

to

be

specifications

procedures

other

setup

of

for the

if

more

of the

test

correctly

.

equipment

may

the equip-

test

to the

infor-

less

are

Performance

ment

canbecheckedwithout

making
Performance

against
column

vided

the
adjustment
settingsorequipment

correct

perform
cedure
circuitsinthis

pletely
form

performing
the

internal

Check

the tolerances

of

Section1.Inaddition,across-referenceispro-

to the stepinPart

instrument

step

Adjustment

calibration

only

Part

gives

the

instrument

Complete

both

Performance

check

PartsIand

the

Performance

and

Adjustment

canbeperformed

Procedure.To

Check.The

adjustments

.

This

listedinthe

I I

to correct

connections

with

II --

Adjustment.The

recommended

.

adjust

II.Start the

Check.Fhis

performance

removing

by

performing

procedure

Performance

--

Adjustment

calibration.In

return

the

minimum

calibration

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all

parts of

procedure

method

checks the

without

.

this

complete

and

will

the

which

changing

this

number

Adjustment
procedure

of

this

instru-

side

shields

only

PartI--

instrument

Requirement

will

return

most

cases,

control

instrument

of

steps,

pro-

for

com-

instrument,

procedure

follow

this

with

assure that the

the

to

all

per-

by

or

Calibration

All
check
items

used
without
capabilities.For
amplitude
Check

check
operation.Equipment
Check

only

for
note2.

Test

Equipment

1.7000-series
Oscilloscope
mended

2.Time-Base

of the

and

adjust

only

compromising

signal

and

may

the

lower

procedure

the

.

Equipment

test

this

for

example,
generatorisused
be deletedifthe

frequency

is

Adjustment

oscilloscope, referredtoas

in

this

plug-in

Alternatives

equipment

instrument.However,

the

Performance

used

indicated

procedure.Tektronix

unit,

the

the

response

only

procedure

Tektronix

is

instrument's

low-frequency

by

required

Check

onlyinthe

user

does

or

for

the

note1;

are

71350

to

completely

some

of

canbedeleted

measurement

constant-

Performance

not

desire

trigger

items

source

Performance

required

indicated

the

Indicator

7403

recom-

.

the

to

by

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Calibration-7A1

3.Amplitude

square

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Pulse

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erator.'Frequency,
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able

from

amplitude

kilohertz

at

50

Tektronix

5.Low-frequency
Frequency
tude, variable
peak.For
General

put)

Radio

.

6.Square-wave

put

capabilities
tors):12
witharisetimeof12
into50ohmsat100

8/7A18N

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accuracy,

recommended

frequency,

50

millivoltsto200

accuracy,

and

SG

503

Signal

range,

two

from

example,

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generator

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volts

amplitude

amplitude,20millivoltsto20

within0.25%.Tektronix

.3

constant-amplitude sine-wave

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50

from

kilohertz

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from50to

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hertzto10

10

millivoltsto400

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274

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be

Radio

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signal,

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signal

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kilohertz

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506

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gen-

megahertz

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within

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out-

out-

genera-

kilohertz

millivolts

nano-

to

.'

14.In-line

;

wattage
BNC.Tektronix

15.10X

racy,

;

011-0059-02

;

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X

20

picofarads;attenuation,2X;

tronix

17.Adapter.Adapts

connector.Tektronix

Adjustment

18.Screwdriver.Three-inch

example,

19.Low-capacitance

Tektronix

20.Tuning
tance
003-0307-00,

BNC

termination.'Impedance,

rating,

two

watts;accuracy,

PartNo.

BNC

attenuator

±2%;connectors,

.

calibration

fixture

PartNo.

Tools

Xcelite

and

R-3323

PartNo.

003-0000-00

tool.Handle with

attenuator

003-0334-00,

±2%

;

011-0049-01

. l

.

Impedance,50ohms;accu-

BNC.Tektronix

Time

constant,

one

connectors,

067-0538-00

GR874

.

connectortoBNC

017-0064-00

shaft,

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.

.

screwdriver.1

1/2-inch

.

inserts

for

input

adjustments.'Tektronix

and

003-0497-00

.

50

ohms

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No

megohm

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male

bit.For

shaft

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.

.

Accessories

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input
017-0064-00

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input.Tektronix

13.1

accuracy,
017-0078-00

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Required

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BNC.Tektronix

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.

Five-nanosecond

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;

.

rating,

two

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with

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.

OX

G

±2%;connectors,

.

only

for

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only

for

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TM

500-Series

PartNo.

50

PartNo.

cable.Impedance,50ohms;type,

GR874.Tektronix

±2%;connectors,

male output.Tektronix

coupler.'Matched

calibration fixture

R

attenuator.2 Impedance,

067-0525-00

GR874.Tektronix

Check

.

procedure

PowerModule

.

.

012-0076-00

ohms;type
012-0057-01

signal

R

G-58/U

.

RG-58/U

.

Part

No

;

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GR874

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No

transfertoeach

.

50

ohms

Part

No

;

;

.

.

;
.

Preliminary

Set the

follows
procedure)

(for

I

ntensity

Focus
Graticule Illum

Calibrator
Vert

Mode

Trig

Source

DISPLAY
TRIGGER
CH2POLARITY

POSITION
VOLTS/DIV
AC-GND-DC

Control

Indicator

both

Settings

Oscilloscope

Performance

Indicator Oscilloscope

7A18

MODE

SOURCE

CH1and

Check

Midrange

Adjust
As

40

1
Left
Left

CH

MODE

+UP

CH

Midrange
10
DC

and

display

desired

mV

kHz

Vert

1

2

mV

7A18

controls

and

Adjustment

for

well-defined

as

5-2

REV.E,

MAY,

1976



1

















Introduction

-

The

following

7A18

without

adjustments.All

basedonSection1of

Index

Factor

(VOLTS/DIV)

IDENTIFY

to PartI---

1 .

Check

2.Check
Accuracy

3.Check

4.CheckChannel

procedure

removing

tolerances

Channel1and2GAIN

Channel

Channel

Range

(7A18

this

manual

Performance

1

and

1

and2VARIABLE

only)

checks

the

the covers or

given

in this

.

Check

2

Deflection

and2Trace

performance

making

procedure

of

internal

Page

Page

Page

Page

5-3

5-3

5-4

5-4

00

the

are

rol

2

.

Connect

which

meets

oscilloscope

3.Turn

least

twenty

given

accuracy

4

.

Set the

Settings

The
both
selectedbythe

the Indicator

the

power

the Indicator

minutes

.

controlsasgiven

.

checks

titled

channels

frequency

supply

warmup

Channel

.

Perform

DISPLA

Performance

Oscilloscopetoa

and

voltage

.

Oscilloscope

for

checking

under

TE

NO

1

and2

the

check

Y

MODE

switch

Check--7A18/7A18N

power

source

requirements

poweron.

Preliminary

apply

on

.

the

the

Allow

7A18

Control

equally

channel

of

the

to the

to

at

5.Check

width

6.Check

quency

Response

7.Check

8.Check

9.Check

10.Check

11.Check

Preliminary

The

performance

at

any

unless stated

1.Install

mentofthe

Channel1and2Upper

Channel

Channel

Common-Mode

Alternate

Chopped

Trigger

Procedure

temperature

otherwise

the

Indicator

1

and2Lower

Isolation

Operation

Operation

Source Operation

for

NO

of

this

within the0°Cto

.

7A18

in

the

Oscilloscope

instrument

Rejection

Performance

TE

left

vertical

.

Band-

Fre-

Ratio

Check

canbechecked

+50

°Crange

plug-in

compart-

Page

Page

Page

Page

Page

Page

Page

5-4

5-4

5-5

5-5

5-5

5-6

5-6

1

.

Check

a.Connect

the

CH

cable

b.Set the

millivolt

c

.

d.If

exactly

in

the

GAIN

e.Set

partscanddof

Channel1and2GAIN

1

and

and

dual-input

square-wave

CHECK--CRT

necessary,

five

GAIN

controlisengaged

the

2.Check
Accuracy

a.Set the

b.CHECK-Using

tude

calibrator

deflection

switch

within

.

the

standard

CH

2 input

coupler

standard

display

adjust the

divisions

knob

with

DISPLAY

this

step

Channel

Channel1AC-GND-DC

settings

2%

amplitude

connectors

.

amplitude

output

.

forafive-division

of

vertical

a

screwdriver

.

MODE

for

Channel2.

1

and

the

VOLTS/DIV

givenin-

in

each

calibrator

with

the

calibrator

front-panel

deflection.To

switchtoCH2and

2

Table

position

GAIN

and

Deflection

switchtoGND

and

standard

5-1,

of the

output

42-inch

fora50-

display

control

adjust,

turn

check

VOLTS/DIV

BNC

.

press

until

repeat

Factor

.

ampli-

vertical

to

for

the

5-3

















Performance

c.Change

DISPLAY
CH

1

CH

2

d.Repeat

VOLTS/DIV

Switch

Setting

Check--7A18/7A18N

the

following

MODE
AC-GND-DC
AC-GND-DC

part b of

this

Standard

Amplitude

Calibrator

Output

step for

TABLE

control

settings

CH

DC
GND

Channel1.

5-1

:

1

Maximum

Error for

Accuracy

(divisions)

±2%

4.Check
(7A18

POSITION

the

partsaand

5.Check

sine-wave
the

termination

division
frequency

only)

a.Center

b.CHECK----Press

trace

moves

c.Set the

d.Disconnect

Connect

a

.

generatortothe

five-nanosecond

b.Set the

display

.

Channel

the

CRT

control

.

upward

DISPLAY

b of

this

step

all

test

Channel

the

medium-frequency

.

medium-frequency

(80

millivolts)atthe 50-kilohertz

1

and

display

the

IDENTIFY

.

MODE

for

equipment

1

and2Upper

7A18

GR

cable

2 Trace

vertically

button

switchtoCH1and

Channel1.

.

Bandwidth

constant-amplitude

CH1input

and

in-line

generator

IDENTIFY

with

the

and

check

connector

50-ohm

for

7A18

that

repeat

with

GR

an

eight-

reference

3.Check
DIV).Range

a.Set the

mV

and

the

ou tput.

b.Press

ward

position

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clockwise,

d.Return

tion

.

e.Change

DISPLAY
CH1AC-GND-DC
CH2AC-GND-DC

.

Repeat

f

Channel

Channel1and2VOLTS/DIV

standard

and

.

check

the

the

MODE

partsb,c,

1

amplitude

release

the

for

two

VARIABLE

following

and

and

2

calibrator

the

VARIABLE

VARIABLE

divisionsorless

control

control

d of

this

VARIABLE

control

to

settings

CH

GND
DC

step

(VOLTS/

switchesto10

fora50-millivolt

controltoits

fully

counter-

deflection

of

the

CAL

:

2

for

Channel2.

c.Increase the

amplitude

d.CHECK----Generator
least50megahertz
hertzina

e.Disconnect

connector

out-

.

IN

posi-

f

g

h.CALIBRATION---See

cedure

i .

6.Check
Response

VOL-T -

AC-GND-DC

.

Set

the

.

Repeat

.

Disconnect

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decreasesto5.6divisions

7500-series,

and

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generator

in

or

the

generator

connectitto theCH2 input

DISPLAY

parts

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all

test

Channel

following

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output

7400-series

a

75

megahertz

MODE

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equipment

1

and

control

frequency

.

frequency;must

outputfrom

switch toCH2

this step

5 of the

.

2

settings

CH

2

5
AC

until

mainframe,

in a

7700-series

the

connector

for

Channel2.

Adjustment

Lower

:

mV

the

60

CH1input

.

Frequency

display

be

mega-

.

.

pro-

at

4

5-