HP 122AR, 122A Service manual

122A

OSGlllOSCOPE

OPERATING AND SERVICING MANUAL

FOR

MODEL 122A/AR

OSCILLOSCOPE

101

SERIAL

AND ABOVE

Copyright HEWLETT-PACKARD COMPANY

275

PAGE MILL ROAD, PAL0 ALTO, CALIFORNIA,

U.

1959

S.

A.

122AQ01

SWEEP

Model 122A

SPECIFICATIONS

Sweep Range: 15 Calibrated sweeps, accurate to within

Sweep Expand:

Synchronization:

Trigger Point: Control overrides automatic ailu

VERTICAL AMPLIFIERS

Bandwidth:

Sensitivity:

*5%,

in a 1, 2,

5

psec/cm to 200 millisec/cm.

Vernier

permits continuous adjustment sweep time between calibrated steps and extends the 200 millisec/cm to at least

X5

sweep expansioil

1

psec/cm.

accuracy Automatic from

0.5

is

40%.

sec/c

lllay

Expansion

50

cps to

uc;

ust;u

is

about the

mu

ail

xaiigcs

center

KC;

internally rrom vertical deflection signals

and expands fastest sweep

of the CRT and expanded

causing 1/2 cm or more vertical deflection; from external signals peak-to-peak or greater, and from

d

+10

-10 an Dperation.

I

matic

DC

coupled: dc to AC coupled: 2 cps to Bandwidth

10

millivolts/cm to

volts. Turning fully counterclockwise into AU1

200

kc.

200

kc.

is

independent of calibrated sensitivity setting.

100

volts/cm.

line

voltage.

,,F;Illllcu

clIF;

LILRRF;l

--

4

calibrated steps accurate within

5,

10,

to be set between

-

r0

restores auto-

...

sequence,

2.5

01

steF

ta

sweep

volts

*5%,

10 mv/cm, 100 mv/cm, 1 v/cm and 10 v/cm. Vernier permits continuous

stem

adjustment of sensitivitv between

and extends 10 v/cm step to at least

100 v/cm.

Internal Calibrator:

Input Impedance:

Phase Shift:

Balanced Input:

Difference Input:

Vertical

Presentation:

Calibrating signal automatically connected to vertical amplifier for standardizing of gain, acc

1

megohm,-apprc

Vertical and hoi

*2"

to 100

10

mv/cm

On by approximate

mode signal mi Both input signals

all

on

vertical sensitivity ranges. The sensitivity switches may be set sep-

:uracy *2%.

50

)ximately

-:.--.-..-I

ilruiiLai

then verniers

kc

w

'ange on both amplifiers. Input impeda

r

ppf.

:ly 25 1st not exceed

may

ppf shunt capacitance.

---1:1:---

amuiiiiers

are

fully

L

----

nave

cw.

-----

same

Common mode rejectionis

*3

volts peak.

IJ~

swiccneu

to

one cnannei to give differential input

-L-

unase

I-

characteristics within

nce,

2 megohms shunted

40

at least

db. Common

arately to allow mixing signals of different levels. Common mode rejection

is

at

least

40

db with

on most sensitive range,

30

db on other

es

ranges.

A

Switch selects:

O~LY,

B

ONLY, B-A, ALTERNATE

or

CHOPPED.

Model 122A

-IORIZONTAL AMPLIFIER

SPECIFICATIONS (CONT’D.)

Bandwidth:

Sensitivity:

Input Impedance:

Phase Shift:

SENERAL

Cathode Ray Tube:

CRT Bezel:

CRT Plates:

DC coupled: dc AC coupled: 2 cps to 200 kc. Bandwidth

0.1 volt/cm to 100 volts/cm. v/cm, 1 v/cm, and 10 v/cm. Vernier permits continuous adjustment

.1

sensitivity between steps and extends 10 v/cm step to

1

megohm, nominal, shunted by approximately 100

Horizontal and vertical amplifiers have same phase characteristics within *2 to 100 kc.

5AQPl mono-accelerator normally supplied; 2500 volt accelerating potential. P7 and special applications.

Light proof bezel provides firm mount for oscilloscope camera and moved easily for quick change

Direct connection

approximately 20 v/cm.

P11

to

200 kc.

is

independent of calibrated sensitivity setting.

3

calibrated steps, accurate within

phosphors

are

also available. P2

of

filter.

to

deflection plates via terminals on

wf.

is

available

at

rear.

least

if

desired for

Sensitivity

.5%,

of

100 v/cm.

is

re-

Intensity Modulated:

Filter

Illuminated Graticule:

Supplied:

Dimensions:

Weight:

Power:

Accessories

Available:

Terminals on Color of

Green with Amber with P7 Blue with

Edge lighted with controlled illumination,

squares. Major horizontal and vertical axes have 2 mm subdivisions, Cabinet Mount: 9-3/4 in. wide, 15 in. high, 21-1/4 in. deep.

Rack Mount:

Cabinet Mount: Net 35 lbs., shipping 51 Ibs. Rack Mount:

115/230 volts

AC-83A Viewing

rear.

+20 v to blank

filter

compatible with CRT phosphor supplied:

P1

and P2

P11.

19 in. wide,

19-1/2 in. deep behind panel.

Net

33

lbs., shipping 48 lbs.

+lo%,

50-1000 cps; approximately 150 watts.

Hood,

face-fitting molded rubber.

trace

of normal intensity.

7

in. high, 21-1/4 in. deep.

10 cm x 10 cm, marked in cm

CONTENTS

SECTION

SECTION I1 OPERATING INSTRUCTIONS

SECTION

SECTION IV MAINTENANCE

111

I

GENERAL INFORMATION Page

1

.

1

General Description

1

.

2

Damage in Transit

1

.

3

Power Line Voltages

1

.

4

Conversion for 230 Volt

1

.

5

Accessories Available

2

.

1

Controls and Terminals

2

.

2

.

2 . 4

CIRCUIT DESCRIPTION

3

.

3 . 2 3 . 3

3

.

3 . 5

.

3 6

Vertical Amplifier Input Considerations

2

Checking Horizontal Amplifier Gair Calibration

3

Operating Drawings

1

General Content Vertical Amplification Channels Horizontal Amplification Channels

4

Sweep Generator High Voltage Power supply Low Voltage Power Supply

..........................

........................

.........................

.

0

.

.............

.......................

..............

..........

........................

..................

.................

..........................

.....................

i

.

i

.

1-1 1-1 1-1

I1 . 1

11

.

I1 . 1 I1

.

111 . 1

111

.

I11

.

111

.

111

. .

111

1 1

1

2

3

3 3

SECTION

V

4-1

4-2

4-3 4-4 4-5 4-6 4-7

4-a

4-9

4

.

4

.

4 . 12

.

4

TABLEOFREPLACEABLEPARTS

5

.

Introduction Front Panel Operational Check Removing the Cabinet

Tube Replacement.

Trouble-Shooting Procedure Condensed Test and Adjustment Procedure

Complete Adjustment Procedure Turn On Procedure

Power Supplies

Trigger Generator

10

Vertical Amplifier

11

Horizontal Amplifier Adjustments Sweep Generator

13

Table

1

.............................

.........................

...........................

.........................

..........................

of

Replaceable

Parts

...................

....................

............

..................

.................

.....................

IV

.

1

IV

.

2

IV

.

5

IV

.

5

IV

.

7

IV

.

9

IV

.

11

IV . 11

IV

.

11

IV

.

12

IV

.

13

IV

.

15

IV

.

15

V . 1

I

I I

I

I I I

I

I I

I

I I

I

CATHODE RAY TUBE WARRANTY

The cathode ray ray tubes purchased from

date

of

sale by the Hewlett-PackardCompany. Broken tubes or tubes with burned phosphor

not included in this guarantee.

Your local Hewlett-Packard representative maintains

glad to process your warranty claim for you. Please consult him.

Whenever out in full and returned with the tube. Follow shipping instructions carefullyto insure safe rival, since no credit can be allowed on broken tubes.

1)

2)

3)

4)

5)

6)

tube

supplied in your Hewlett-Packard Oscilloscope and replacement cathode

@

,

are guaranteed against electrical failure for one year from the

a

stock of replacement tubes and

a

tube

is

returned for a warranty claim, the reverse side of this sheet must

SHIPPING INSTRUCTIONS

Carefully wrap the

padding material.

Wrap the above in heavy kraft paper.

Pack in a rigid container which

the tube in each dimension.

Surround the tube withat

similar shockabsorbing material. tight

all

around the

Tubes

Ship prepaid preferably by AIR FREIGHTor RAILWAY EXPRESS.

We do not recommend parcel post or

returned from outside the continental United States should

be

packed in a wooden

tube

in

tube.

box.

1/4"

thick cotton batting or other soft

is

at least 4 inches larger than

least

four inches ofpackedexcelsior or

Be

certain that

air

parcel post shipment.

the

packing

is

be

will

filled

are

be

ar-

HEWLETT-PACKARD

co.

275

PAGE

MILL

ROAD,

PALO ALTO,

CALIF.

U.S.A.

FROM:

COMPANY:

ADDRESS:

Person to contact for further inform NAME

TITLE COMPANY: ADDRESS:

To process your claim quickly pl

1)

2)

:

@INSTRUMENT MODEL

TUBE TYPE

ease

-

CRT WARRANTY CLAIM

~~~~~~~

enter the information indic

SERIA: SERIA:

:ated

L

below:

I

DATE:

I

3)

ORIGINALTUBE

4)

YOUR PURCHASE ORDER NO

5)

DATE PURCHASED

6)

PURCHASED FROM

7)

COMPLAINT: (Please describe nature

~~~

8)

OPERATING CONDITIONS: (Please describe conditions prior to and

REPLACEMEN

of

trouble)

SIGNATURE

r

TUBE

at

time of failure

I

‘9

Model 122A Sect. I Page

1

SECTION

GENERAL INFORMATION

1-1 GENERAL DESCRIPTION 1-3 POWER LINE VOLTAGES

The Model 122A

cathode-ray oscilloscope. It has accurately brated input sensitivity and sweep-speed ranges.

This oscilloscope features dc-coupled differential

amplifiers and dual-trace operation.

Differential amplifiers the common-mode (in-phase) part

amplifying the differential (out-of-phase) part. For

instance, they plifying the desired signal. In addition, using differential amplifiers has other advantages. Normally dc amplifiers are difficult Changes such as aging and changes of potentials

cause

the common-mode type and ferential amplifiers. Thus differential amplifiers are also used

this drift. However, these changes are of

is

a dc

to

200 kc dual-trace

are

useful since they reject

of

the input

will

reject hum pick-up while am-

to

are

rejected by dif-

to

stabilize dc amplifiers.

cali-

while

keep stable.

This instrument inal 115 or operate satisfactorily over a the nominal value,

130/260 volts normally high line voltage line voltage

127 volts.

1-4 CONVERSION FOR

The instrument can be converted from 115 v

230

v operation by reconnecting the power transformer dual primary windings as follows: Remove the instrument from the cabinet by removing the two large the instrument from the cabinet by pushing on the

rear

screws

of

the chassis.

is

designed to operate from a nom-

230

volt

source.

i.e.

103-127 volts. Operationat

will

damage the instrument. If ab-

to

be certain

from the rear

The instrument

*lo%

is

suspected monitor the

it

does not exceed

230

VOLT OPERATION

of

the cabinet. Push

1

will

variation from

to

Dual-trace operation switch. at the same time. The two signals may be viewed either alternately during consecutive sweeps chopped on each sweep. Chopped operation involves switching rapidly between the both appear to be traced simultaneously. The most useful type upon the frequencies involved. Generally, chopped operation signals may difference

1-2 DAMAGE

Refer damage

This

permits observation of

of

presentation in each

is

used with low frequency signals. These

also

(B-A)

to

the warranty page in this manual

is

apparent upon receipt.

is

obtained with an electronic

two

signals

or

two

signals

case

be viewed separately or with their

displayed on the screen.

IN

TRANSIT

will

so

that

depend

if

any

Locate the next

to minals on each side ing the windings in parallel. Remove these jumpers. Connect an insulated jumper between the second and fourth terminals, connecting the windings in

series.

Schematic blow fuse with a 1.0 amp slow-blow fuse.

1-5 ACCESSORIES AVAILABLE

An AC-83 Viewing

is

This shade the ambient light conditions. It

lower

power

the power transformer. The twoouter

Refer

for

a face-fitting moulded rubber hood used

face

beam intensity setting.

supply terminal strip situated

are

jumpered together connect-

to

the Low Voltage

details. Replace the 2.0 amp slow-

Hood

is

available

of

the cathode-ray tube under high

will

Power

at

extra cost.

permit the useof

ter-

Supply

to

Sect.

11

Page

0

e

c

Y

VI

Model

122A

c

I

\\

\

I

\

I

E

c

C

2

Y

I

I II

I

122A

Sect. I1 Page

1

P

ONTROLS AND TERMINALS

2-1

briefly shows how

nt. Additional detailed information

VERTICAL AMPLIFIER INPUT :ONSIDERATIONS

exceed the common-signal voltage limit

my conditions. This limit

Note

rid.

-

c

plus peak ac).

he

attenuators are used the voltage to the

brminals may

the

attenuation as follows:

to

operate the in-

is

*3

that this

be

TABLE

is

the sum of

increased by the amount of

2-1

is

given

volts on the

all

volt-

SECTION

II

OPERATING INSTRUCTIONS

C. Other Types of Input Other types of input

balanced input with either dual or single channel operation

as

with most other types that ranges must be observed. Thus the commonsignal limit since there red input terminal and the input grid. The red terminal does not have an attenuator between it and its input grid.’ Therefore balanced input with attenuation channel without external attenuators. However, this

may be accomplished using both channels paragraph B above and Figure

is

possible

it

may only be used on the

is

*3

is

an attenuator only between the upper

are

possible. For example,

(see

Figure

of

volts. This limitation

is

not possible using only a single

2-4).

However,

input, the limitation

.01

VOLTS/CM

is

necessary

2-3).

lower

(see

Attenuator Setting Common-Signal Limi

0.01

VOLTS/CM

0.1 1

.o

10

NOTE Maximum peak input voltage limit

volts (dc plus peak ommended ways

fer

to

Figures

cerning connections.

A.

Unbalanced Input

Maximum voltage limit

B. Differential (B-A) Input (see Figure Maximum voltage limit from each line

as

in table

least

40

VOLTS/CM. ranges, functions of the controls

2-1.

db with both switches

Rejection

ac).

The following are

of

connecting the oscilloscope. Re-

2-1

to

2-4

for further details con-

(see

Figure

as

in table

Common-signal rejection

is

at least

2-2)

set

volts

*3 30

300

500

is

600

rec-

2-1.

2-3)

to

ground trations that follow.

is

at

on

10

MILLI- model. The location of the controls on the front

30

db on other panel

2-3

CHECKING HORIZONTAL AMPLIFIER GAIN CALIBRATION

The horizontal amplifier may be calibrated by comparing it with the vertical amplifier. First, calibrate the vertical amplifier as shown in Figure Set both VERT. and HORIZ. SENSITIVITY switches to

0.1

VOLTS/CM with VERNIER’S in Cal. Feed

1

an external zontal input terminals. Adjust the input amplitude for

a

10

R114,

2-4

Basic operating procedures are shown in the cabinet model but are the same for the rack mount

for exactly

OPERATING DRAWINGS

is

volt signal into the verticaland hori-

cm high pattern. Set Horiz. Gain Adj.,

10

cm of horizontal deflection.

Directions are given for the

different in the rack mount model but the

are

2-10.

illus-

the same.

Sect.

I1

Page

2

UNBALANCED INPUT

mim

A VERT SENSITIVITY

Model

I

122A

3

\

1.

CHANNELA POLARITY

pos

UP

NE6

up

YODEL

0

SCI

c'i

'P~E

L

J

Connect input to red terminals with ground

to lower terminal.

Follow same procedure for other channel.

Figure

2-2

:1

122A

Sect.

I1

Page

3

BALANCED

INPUT

/L

Connect one lead

1.

YODEL

-JI

0

SCI

L

112.

COP

to

top terminal

nel and other lead to other channel.

2.

Set VERT. PRESENTATION to B-A.

3.

Set

both

VERT.

SENSITIVlTY

(same) sensitivity desired

Figure

2-3

of

switches to

(AC

or DC range).

one chan-

Sect.

I1

Page

4

Model

122A

BALANCED INPUT

.01

VOLTS/CM SENSITIVITY ONLY

VLI*ILR

A

VERT SENSITIVITY B VERT SENSITIVITY SWEEPTIME

"EIWlLl

vLI)yDI

,

WIZ

SEM

Balanced input may CM

ranges (AC

be

used only on

or

DC) because only the upper red

the

.

OlVOLTS/

terminal has an attenuator in series between and the amplifier input grid.

To

connect proceed

1.

Disconnect ground strap. Connect input to red terminals.

2.

as

follows:

I

it

Figure

Set

3.

4.

5.

VERT. SENSITMTY

CM

(AC or DC).

Set

VERT. PRESENTATION

Set

CHANNEL

sired.

A POLARITY

Channel

B

may

ilarly. Both channels may and observed with either CHOP. presentation.

2-4

switch

to

to to polarity de-

be

connected

be

.01

VOLTS/

A.

connected

or

sim-

ALT.

Model

122A

INTERNAL SWEEP - INTERNAL SYNCHRONIZATION

Sect.

I1

Page

5

1.

Feed vertical input signal(s) into vertical input

terminal(s).

2.

Set

VERT. PRESENTATION

presentation.

3.

Adjust VERT. SENSITIVlTY

sired sensitivity.

and

DC

coupled ranges.

(Note

switch to desired

switch(es) for de-

that

there are

)

both

AC

Figure

4.

Set

slope

5.

Set

sired

6.

E

AUTOMATIC

TRIGGER

trigger point.

2-5

SYNC

switch

of

trigger

SWEEP TIME

sweep speed.

LEVEL

T(+

€€OR

is

control

or

SENS.

not desired, rotate

to

point desired.

-

sweep

-),depending upon

switch for de-

select level of

Sect.

I1

Page

6

CH

0

PP

ED

0

PER

AT1 0 N

Model

122A

.

’-

d

Usefulfor observing low frequency signals (less than approximately ternally

1.

to

avoid

Connect signal

channel

A.

2

kc). Synchronize sweep ex-

“Jitter”.

(1)

to

two

red terminals of

Figure

2.

Connect signal of channel

3.

Set VERT. PRESENTATION

4.

Connect external sync signal.

2-6

B.

(2)

to

the

two

red terminals

to

CHOP.

Model

122A

ALTERNATE SWEEP OPERATION

/

Sect.

I1

Page

7

Useful (above approximately

1.

2.

3.

for

observing higher frequency signals

2

kc).

Connect signal channel

A.

Connect signal channel

B.

to

two red terminals

to

two

red terminals

Set VERT. PRESENTATION this method speeds. Since each

of

presentation

is

individually triggered,

to

for

ALT.

fast

this presentation can be used with internal

of

Use

sweep

Figure

triggering even when the

two

signals

related in frequency. When operating in this

of

manner the intensity

reduced

if

the

traces

the traces

are

separated on the screen. This may be eliminated by adjusting the VERTICAL POSITION controls the

traces

overlap. Usually operation

involve signals related in frequency.

if

it

is

desired to maintain phase information between the necessary is

the

then possible

case,

two

signals being viewed,

to

use

external triggering. If this

use

external triggering. It

to

separate the traces without

intensity reduction.

2-7

ares

will

be

so

that

will

Also,

it

is is

Sect.

I1

Page

8

INTERNAL SWEEP - EXTERNAL SYNCHRONIZATION

B

VERT

SENSITIVIT

Model

122A

UL

RO

1.

Feed vertical input signal(s) into vertid input

terminal(

2.

Set presentation.

3.

Adjust VERT. SENSITIVITY switch(es) for desired sensitivity. (Note and low 2 cps above

put.

in low-frequency square waves.

s).

VERT.

DC

PRESENTATION switch to desired

coupled ranges.

or

to preserve

2

cps or to eliminate dc component in in-

AC

coupling may introduce excessive

I

that

there are both AC

)

Use DC

dc

level. AC couple

coupling

be-

tilt

The sum of the dc and peak ac applied to the

INPUT

4.

Feed synchronizing into external synchronizing terminals which

ac

5.

Set SYNC switch to EXT.

6.

Adjust SWEEP TIME - HOR.

desired sweep speed.

7.

If

TRIGGER LEVEL control to select level of trigger point.

terminals must not exceed

signal

coupled.

AUTOMATIC sweep

AC

-DC

switch

600

(2-1/2v p-p or more)

has

no effect.

SENS.

is

not desired, rotate

switch for

volts.

are

Figure 2-8

Model

122A

VERTICAL BALANCE ADJUSTMENT

Sect.

I1

Page

9

1.

Set

both

VERT. SENSTI'IVITYswitches to OFF. 4. Center trace with VERT.

2.

TurnbothVERT.

SENSFlWTYVERNIERsfully

5.

Turn VERNIER fully clockwise.

counter-clockwise.

6.

Adjust BAL control

3.

Set VERT. PRESENTATION switch to A. Repeat procedure for Channel B.

Figure

2-9

to

center

POS.

trace

no

control.

or spot.

Sect.

I1

Page

10

VERTICAL SENSITIVITY CALIBRATION

Model

122A

mien

A

MRT SENSITIVITY 0 VERT SENSITIVITY

1.

Set A VERT. SENSITIVITY switch position. of

2.

Set

3.

VERNIER

Set

VERT. PRESENTATION switch

to

CAL. position.

to

vEnmn

CAL.

to

A. VERNIERS

b

4.

Adjust

The vertical amplifier the engraved markings on controls

GAIN

6

cm. Repeat

are

accurate within

are

control to give a pattern height

this

in CAL.

M)

procedure for Channel

is

now

the

calibrated

VERT.

+5%

whenever

so

SENSlTIVlTY

B.

that

the

Figure 2-10

Mod€

:1

122A

Sect.

I1

Page

11

r

INTERNAL SWEEP MAGNIFICATION

/

A

VERT

WnlcR

SENSITIVITY

e

VERT

"ERllEl

SENSITIVITY

VEwm

SWEEPTIME

KRIZ SENS

1.

Make

sure

SWP.

EXP. switch in in

2.

After obtaining pattern, center the meters of pattern to

axis

vertical

with

be

HORIZ.

magnified on center

POS.

Xl

position.

two

control.

centi-

Figure 2-11

3.

Set SWP. EXP. switch to X5.

Any two cm portion of pattern may

be

viewed magnified five times by adjustment

HORIZ.

POS.

control.

be

selected

to

of

Sect.

I1

Page

12 Model 122A

EXTERNAL HORIZONTAL INPUT

7'

1. Feed horizontal

signal

to horizontal input ter-

CHANNELA POLARITY

VERT PRESENTATION

3.

TRIGGER LEVEL

Set

SWEEP

minds. desired sensitivity.

2.

Set

AC-DC

switch for type of input coupling

This type of input will

desired. Lissajous patterns, etc.

Figure

2-12

TIME

RO

-

HOlUZ.

be

SENS.

switch for

found useful for viewing

'1

122A

HORIZONTAL

INTENSITY MODULATION OPERATION

dYICAL

D3

Sect.

I1

Page

13

03

L

REAR

T

VIEW

OF INSTRUMENT.

POSITIVE DEFLECTS UP

I

!

LDY-174

I

AUTION - The deflection plates of the oscil- To intensity modulate with an external signal:

Iscope operate

URN

THE INSTRUMENT OFF BEFORE RE-

at

a

dc potential above ground.

OVING THE COVER PLATE FROM THEDE-

Remove the vertical jumper marked

2.

Connect the external intensity modulation

Z-axis.

1.

LECTION PLATE TERMINALS, TO AVOID signal to these terminals (a negative signal OMING

IN

CONTACT WITH

HIGH

VOLTAGES.

will

brighten the trace).

Figure

2-13

Sect.

I1

Page

14

Model

122A

/

I

./.----

TOP

-.

OF

CASE

-.--

CONNECTION

HOR/Z.

/wur

-

REAR VIEW OF INSTRUMENT.

TO

DEFLECTION

VERT

iwur

PLATES

-.-.-.

LO-M-169

-.

'\.

\

i

RO

CAUTION

To connect an external signal to the deflection plates:

-

Deflection plates of cathode-ray tube operate BEFORE REMOVING COVER PLATE FROM DEFLECTION PLATE TERMINALS.

I

A.

AC COUPLED

1.

Remove the jumpers going to terminals D1 and D2 for horizontal input and/or D3 and

D4 for

2. Connect

of

3. Connect the to terminals D3 and

put blocking condensers to D3 and D4.

The POSlTION controls on the 122A trol the pattern and good focus

vertical

1

megohm 1/2

the jumpers removed in step

input.

vertical

watt

input

D4

resistors in place

blocking

and

the

will

1. condensers

horizontal in-

will

still

con-

be maintained.

Figure

at

high dc potentials. TURN 122~ OFF

B. DIRECT COUPLED

1.

Remove the jumpers going to terminals D1 and D2 for horizontal input and/or D3 and D4 for vertical input.

2. Connect leads from the vertical input directly to D3 and D4 and the lead from the horizontal input directly to D1 and D2.

POSITION controls Position voltages source. Best picture focus

plates are at +275V with respect to

2-14

will

no longer control pattern.

must

be furnished

is

obtained when

122A

by

the signal

chassis.

Model 122A Sect.

I1

Page 15

ALIGNING

SCOPE TRACE

WITH

GRATICULE

To align oscilloscope trace with graticule,

move oscilloscope from cabinet; then

1.

Loosen locking clamp with screwdriver.

2.

Adjust fiber lever to adjust position

ray

tube

in

both

radial

and longitudinal direc-

of

cathode-

re-

tions. CAUTION HIGH VOLTAGE. TAKE CARE NOT TO TOUCH TERMINALS WHICH HAVE A HIGH POTENTIAL ON THEM.

When the cathode-ray tube is tighten locking clamp and replace instrument

in cabinet.

Figure 2-15

in

desired position

Sect.

I1

Page

16

CONNECTING EXTERNAL CAPACITORS TO EXTEND SWEEP TIME

Model

122A

4

CAPACITORS

-SIDE OF FRONTPANEL

-

TOP OF

rhe slowest calibrated sweep provided strument vith the SWEEP TIME VERNIER to af least ;econd/cm or 5 seconds for the

f

you wish a slower sweep the range can be exended indefinitely apacitors to the sweep circuits.

'0

'abinet.

. .

Connect external capacitor from point shown

to ground.

is

1/5

second/cm. This can

by

connecting a pair of external

extend the sweep time, remove chassis from

Connect external capacitor across capacitor shown on SWEEP TIME/CM switch.

FRONT

full

10

IN

PANEL IN RACK-MOUNT MODEL

on

the in-

be

extended

cm sweep.

CABINET

1/2

C A PAC1

MODEL

Values of both capacitors are the same and

be determined by the sweep speed desired. that the only ranges that these capacitors affect are the

ranges. proportion to the amount of capacity added to the circuit. calibration

.5,

1,

and 2 seconds/cm respectively.

The capacitor mentioned must be a high-quality type such

loss of sweep linearity occurs these specifications

tor

is

connected to the hold-off circuits and does

not require special characteristics.

50,

100

and

200

MICROSECONDS/CM

The extension of the sieep time

Using

2

pfd capacitors

of

the above ranges to approximately

in

is

used. The second capaci-

will

step 1 of this figure

as

if

a

capacitor with

TORS

a0

Note

is

increase the

mylar.

wil:

will

in

No

Figure

2-16

Ma

del

122A

Sect.

111

Page

1

D

GENERAL CONTENT

3

-1

Thj

is

section contains a description

of

the Model 122A Oscilloscope. The material in

this

3

section

!

Vertical Amplification Channels

3-2

i

Horizontal Amplification Channel

3-3

.

Sweep Generator

3-4

I

High Voltage

3-5

I

Low Voltage Power Supply

3-0

I

3-1

Bot

.h channels

wil:

1

be given. The vertical amplifier receives

the

input signal, amplifies

def:

lection plates. It provides attenuation

inpi

ut signal, determines the vertical position

the

spot on the screen, and supplies a signal

intc

xnal synchronization. The signal comes into

the

input terminals and

the VERT. SENSITIVITY switch. If the switch

of

1

is

<

3n an AC range the signal goes through a capa-

citc

)r.

s

directly

goe

:e

thrc

str;

light-through range, an

inpi

it grid

CAI

L.

position the calibrator output

the

vertical

nected

con neo

n-lamp relaxation oscillator.

Ver

.tical Amplifiers

-

!

vertical amplifiers consist

The cha

nnels of amplification, witching multivibrator, and

a

s\

:h vertical amplifier

Eac

pled differential amplifiers in cascade. The

cou: inpi

it

amplifier in each channel has the BAL. control

ween

is

as

follows:

Power

VERTICAL AMPLIFICATION CHANNELS

are

similar

If the switch

to

the attenuator.

frequency - compensated attenuators,

is

shorted, and a CAL. range. In the

amplifier input and plate voltage

to

the calibrator. The calibrator

its

cathodes. The VERT. SENSITIVITY

Supply

so

it,

anddrives the vertical

is

fed tothe AC-DC section

is

on

a

OFF

a

is

composed of three dc-

of

the operation

only one description

Dc

range the signal

The attenuator has

range where the

is

connected to

of

two identical

switching amplifier,

a

trigger amplifier.

SECTION

C

I

R

C

U

IT

DES

VERNIER and the GAIN control plates

and output amplifier in each channel have plate-to-

grid neutralization. The VERTICAL POSITION control plifiers. the switching amplifiers since the cathode current

for

ing amplifiers. The switching amplifiers in turn

are

The VERT. PRESENTATION switch

type

A

The locked state

ENTATION switch

of

the

for

is

that the multivibrator can be locked in either of

of

two

The other channel in each

the B-A position Channel B

ALT.

The bi-stable

ENTATION switch

a

stable in either

when operating in the ALT. position, Channel

off

received from the sweep. Then Channel

is

on and Channel B

a

repetitive and occurs at the end of each sweep.

CHOP

In the CHOP. position the multivibrator

The circuit

at

position, the tween the

B-A

-

In the B-A position the signal fromchannel B input

is

of

the input amplifier. The secondamplifier

is

between the cathodes of the second am-

The output amplifiers

the output amplifiers

controlled by the switching multivibrator.

of

vertical amplifier operation as

or

B

is

possible states (Channel A on or Channel B on).

state

of

and Channel

an approximately

two

fed directly into the channel B amplifier. The

B

is

a

free-running multivibrator running

trace

channels

is

furnished by the switch-

used

when theVERT. PRES-

is

set

to

case

is

used when the VERT. PRES-

is

set to ALT. Bi-stable means

two positions.

is

on until a trigger pulse

is

turned off. This action

40

kc

rate.

is

switched back and forth be-

at a 40

C

R

I

PTI

are

between the

are

controlled by

selects

A, B or B-A.

is

biasedoff. In

locked on.

For

A

is

Thus, in the CHOP.

kc

rate.

Ill

0

N

the

follows:

Note

example,

A

is

turned

is

astable.

Sect.

III

Page 2

Model 122A

CHANNEL

A

e+

f

CHANNEL

B

OFF

0

ATTENUATOR

CALIBRATOR

ATT E N U ATOR

Figure

4)

I

(DIFFERENTIAL)

3-1.

(40KC)

8-A

Model 122A Block Diagram

DIFFERENTIAL

AMPLIFIER

3

STAGE

DIFFER ENTIA

AMPLlFl ER

I

L

-

--

I

I I

A

input

is

signal from Channel side of the Channel output

of

the Channel B amplifier

B

differential amplifier. The

ference between the Channel B and Channel signal. This

3-3

HORIZONTAL AMPLIFICATION CHANNELS

is

the only signal shown on the screen.

The horizontal amplifier receives an input either from the horizontal input terminals

fedintothe opposite

is

then the dif-

A

signal

or

from the internal sweep generator, amplifies the signal, and drives the horizontal deflection plates. horizontal amplification channel tenuation

of

the input signal, magnification of the

also

provides

The

at-

internal sweep, and determines the horizontal position of the

The signal comes into the input terminals and fed

to

AC position the signal goeb through If this switch

trace

on the screen.

the AC-DC switch..

is

in the

DC

is

If

this switch

is

a

capacitor.

in the

position the signal goes straight through. The horizontal input signal then goes through the horizontal sensitivity section the SWEEP TIME - HORIZ. SENS. switch.

of

This

switch has a three-position frequency compensated attenuator.

A

signal

is

fed

into the horizontal amplifier. This

signal may be either the horizontal input signal or

a

sawtooth signal from the sweep generator. The

position of the SWEEP TIME-HORIZ. SENS. switch

will

determine which signal

fier.

The amplifier consists

is

fed into the ampli-

of

two

differential

amplifiers in cascade. Plate-to-grid neutralization

is

used in both stages. The input differential amplifier, grid

of

POS.

VlOlA,

is

driven single-ended. The

the undriven tube, VlOlB, goes to the HORIZ.

potentiometer.

Two

potentiometers, HORIZ. SENS. VERNIER and Horiz. Gain, in the cathode circuit of potentiometers SWEEP TIME-HORIZ. SENS. switch HORIZ. SENS. ranges. the SWEEP EXPAND switch

X1

or the X5 resistor legs may tween the cathodes tiometer and between the plates other differential amplifier, V102. V102

goes

VlOl

provide gain adjustment. These

are

in the

circuit

only when the

is

in the

In the SWEEPTlME ranges

is

used. 'Either the

be

switched be-

of

V101. A

a

Phase. Adj. condenser

of

V101.

Horiz.

Tube

Bal. poten-

are

connected

VlOl

The

feeds

output of

to the horizontal deflection plates.

an-

Model 122A Sect.

111

Page 3

3-4

SWEEP GENERATOR

The sweep generator consists of a trigger generator and a sawtooth generator. The trigger generator

receives the synchronizing signal, selected by the SYNC selector, and generates a pulse which itiates the action of

the

sawtooth generator. The

in-

sawtooth generator then goes through one complete cycle. It automatically

shuts

itself

off bymeans of feedback upon completion of one cycle. The sweep circuit

will

operate again

when

another pulse

is

received from the trigger generator, but only after a hold-off time during which all of had time to delay

is

necessary

return

to

their

quiescent voltages. This

so

that successive waveforms

the

circuits have

will start from the same voltage each time.

Trigger Generator The trigger generator consists of a synchronizing

circuit and a trigger generator, V201. The

syn-

chronizing circuit receives a signal either from

the

vertical amplifier for internal synchronization

(+

or

-),

from an internal 6.3 volt source for line

the

frequency synchronization, or from

horizontal input terminals for external synchronization. The trigger generator converts the signal into a fast, constant-amplitude pulse for operation of the startstop trigger, V202.

The trigger generator, V201, with narrow hysteresis limits.

is

a Schmitt Trigger

A

negative signal

starts the action by causing the trigger generator

to change state. This action generates a square

is

wave output. This square wave output

differentiated by L201 into a series of positive and negative pulses. These pulses are fed to the start-

s

top trigger.

Sawtooth Generator The sawtooth generator consists of a start-stop

trigger, an integrator switch, an integrator, and a hold-off cathode follower. The pulse from

the

trigger generator controls the start-stop trigger

in

which,

turn, controls the integrator switch. The integrator switch controls the action of the integrator. The integrator generates a linear, rising, voltage. This action

plus

the switching

action of .the integrator switch generates a sawtooth

is

voltage. This sawtooth voltage

fed to the horizontal amplifier and to the hold-off cathode follower. The output of the hold-off cathode follower the grid of the start-stop trigger. keeps the start-stop trigger from triggering

all

the circuits have had time to recover to their

is

fed to

This voltage

until

original quiescent voltage.

Gate Cathode-Follower Another function of

a positive pulse to unblank

This pulse

is

Normally the voltage applied to the grid cathode-ray tube cuts

the

sweep

obtained from

off

generator

the

start-stop trigger.

the

beam. During

is

cathode-ray tube.

to furnish

of

the

time of the sweep operation a positive pulse is applied which overrides

negative voltage and

un-

the

blanks the picture.

3-5

HIGH VOLTAGE POWER SUPPLY

The High Voltage Power Supply consists of a Hartley

Oscillator feeding two separate secondary windings

and rectifiers.

Hartley Oscillator

The Hartley Oscillator consists of a pentode, V302, and a tapped winding on

the

high-voltage transformer. This circuit oscillates at approximately 100 kc. The high-voltage transformer has two separate secondaries and feeds two separate recti-

fier tubes. Output of one rectifier, V304, nected to the grid of

INTENSITY control

ply determines the voltage on

thus

and ing pulse

the brilliance

is

also direct-coupled to

hence to the grid of

the

from

other rectifier of the cathode-ray tube. Voltage supply and fed

into

the

cathode-ray tube. The

in

the

output divider of this sup-

the

CRT control grid

of

the

pattern. The unblank-

this

the

cathode-ray tube. Output

is

connected to

is

taken from

the

input of a two stage dccoupled amplifier. The output of this amplifier fed back to the screen of

the

proper phase to oppose any change

the

Hartley Oscillator

is

con-

supply and

the

cathode

this

is

in

the dc

output of the cathode supply. The Intensity-Modulation terminals are ac coupled

to

the

voltage

cathode of

input

the

cathode-ray tube. A negative

will

brighten the trace while a positive voltage of approximately twenty volts will blank the tube from normal intensity.

3-6

LOW VOLTAGE POWER SUPPLY

The

Low Voltage Power Supply consists of three

regulated supplies, one positive and one negative

and a dc filament

supply.

Positive Voltage Supply

The Positive Voltage supply furnishes

+

380 volts

and +lo0 volts. It consists of a transformer, four

Sect.

111

Page

4

silicon rectifiers, a pentode amplifier and a triode

in

regulator

figuration, and a triode cathode-follower. Full output of the supply ode-follower drops this down to furnish +lo0 volts. Neon tube, V315, protects V307B from excessive

cathode-to-grid voltage during warm-up.

Negative Voltage Supply The Negative Voltage Supply furnishes

and -30 silicon rectifiers, and a erence tube combination power supply configuration. The

the usual regulated

is

+380 volts. The output cath-

volts.

It consists

regulator-amplifier-ref-

power

supply con-

-150

of

a transformer, two

in

the usual regulated

-30

volt output

volts

is

Model

used

as

a filament reference voltage and fed to the

the

center tap of Regulated Filament Supply This supply furnishes regulated

heaters of the four input tubes plifier. These tubes, nected in series-parallel. By supplying this filament voltage from drift

is

greatly reduced.

The

supply consists of a transformer, a silicon

rectifier, and two pnp transistors. Transistor

is

the

series

emitter follower controlling 4301. Reference voltage

is

obtained from the -150 volt supply.

Hum Balance potentiometer.

+24

volts to the

of

the vertical am-

V1,

2,

and

V4,

a

regulated source vertical trace

element. Transistor

122A

5 are con-

4301

4302

is

an

Model

122A

Sect. IV Page

1

SECTION

IV

MAINTENANCE

I-1

INTRODUCTION

This section contains instructions justing, and trouble-shooting the Model 122A cilloscope.

The Front Panel Operational Check, paragraph 4-2, is

a

fast method instrument. The Trouble-Shooting Procedure, paragraph 4-5, section The Condensed paragraph 4-6,

basic

Test Procedure, paragraph 4-7, the condensed

Paragraphs 4-3 and 4-4 contain information on

I

removing the cabinet and replacing tubes. Schematic Diagrams and the Table

Parts

of

the instrument that

adjustments

are

of

checking the operation

is a rapid means of isolating

Test

and Adjustment Procedure,

is

a

fast

method

of

the instrument. The Complete

test

and adjustment procedure.

located at the end

for

testing, ad-

is

not functioning.

of

checking the

is

an expansion

of

Replaceable

of

this section.

of

Os-

the

a

of

YZE

4

AI EXTRA DATA SPECIFICATIONS.

In general, the Model 122A can be divided into sections with the located behind the front panel controls for that section. The on the top chassis brace. Thematerial that

is

divided into sections according functions. Each section has adjustment instructions.

The following and adjusting the Model 122A Oscilloscope during manufacture. Equivalent used for testing purposes.

1) “Reference Oscillator” with frequency range 400 cps

5

millivolts

Wide Range Oscillator.

to

RTICULAR INSTRUMENT. THIS

P.

CANNOT BE CONSIDERED AS

parts

power

test

500 kilocycles, and adjustable output

to

20 volts, such

for

any particular section

supplies

equipment

test

are

in the

rear

and

follows

to

circuit

a

complete

is

used

equipment may be

as

@Model 200CD

for

set

testing

of

F

Standard, readily available components for

manufacture sible. Special components from the source local stock please specify instrument model and serial number plus the component description and stock number appearing in the Table

Your plete

assist

or

repair

ments SPECIFICATIONS FOR THE @ 122A OSCILLO-

SCOPE ARE GIVEN IN THE FRONT OF THIS MANUAL. THE SERVICE PROCEDURES THAT FOLLOW CONTAINEXTRADATATOHELPYOU

@

for

@

representative who maintains a parts

for

your convenience. When ordering

local

facilities

you with any engineering, application,

problems you may have with @instru-

.

of

@

instruments whenever

are

available directly

factory. Perhaps the most convenient

spare

@

or

replacement parts

of

Replaceable

representative

and specially trained personnel

also

maintains com-

are

is

used

pos-

your

parts,

Parts.

to

test,

2) “Reference VTVM” with

to

500 kilocycles frequency range, and 50 milli-

volts

to

60

volts voltage range, suchas the @Model

400H Vacuum Tube

3) “Marker Generator” with frequency range 200 kilocycles

steps and an accuracy Tektronix 180 Time Mark Generator.

4) “Calibration Generator” furnishing lOOv dc and

100

v

ac

at

400

curacy

erator”

the voltage to 20 millivolts in uation with an accuracy cation 23678 meet these specifications.

5)

steps from Attenuator

of * 0.25%. In addition the “Calibration Gen-

must have an attenuator which

“Adjustable Attenuator” having adjustable db

or

Voltmeter.

to 1 cycle per second in decade

or

1000 cps,

Voltmeter

1

to

110

equivalent.

1%

accuracy, 400 cps

of

*0.3%,

all

voltages with an ac-

a

of

*0.25%. The @ Specifi-

Calibration Generator

db.

Use

such

as

will

reduce

1-2-5 times atten-

an @ Model 350A

of

the

will

Sect.

IV

Page

2

6)

“Square Wave Generator” capable of furnishing

square waves or pulses, audio frequencies, such

as

the @Models

4-2

Perform the following procedure whenever there is the instrument. This

if

sociated equipment. Always perform ation Check before attempting instrument adjustment or repair.

For a Proof-of-Performance Check complete the steps as given and compare the specifications. strument up for at least fifteen minutes.

A.

1)

Figure

2)

shown function properly, section of the maintenance procedure before proceeding further.

B.

FRONT PANEL OPERATIONAL CHECK

any question about the proper functioning of

the malfunction

in

ADJUST

CALIBRATION

Check the vertical dc balance as shown in

2-9.

Check the vertical sensitivity calibration as

in

VERTICAL AMPLIFIER SENSITIVITY

211A

and

212A.

will

enable you to determine

is

in

this instrument or as-

this

Oper-

results

All

tests are made with the

the cabinet and the instrument warmed

DC

Figure

BALANCE

2-10.

refer

If these controls donot

to VERTICAL AMPLIFIER

AND

with the

VERTICAL

in-

Model

2)

Connect tion Generator” to input terminal trace should

refer

tenance procedure.

3)

Check dc voltage from the “calibration generator”

As

on. spot should shift VERTICAL POSITION

4)

Check the accuracy of the remaining VOLTS/CM positions.

and gives peak-to-peak and

should produce the deflection listed.

5)

Repeat steps 3 and 4 using the A VERT. SEN-

SITIVITY AC ranges.

6)

Repeat above procedure for channel B.

C. VERTICAL AMPLIFIER BANDWIDTH

1)

Set VERTICAL PRESENTATION to

A TRIGGER LEVEL to AUTO.

2)

Connect the

minal “reference vtvm”.

3)

Set “reference oscillator” to 2 kilocycles and

adjust for “reference vtvm”.

a

0.1

volt

ac

signal from the“Ca1ibra-

The vertical

A.

be

10

cm

*5%

(9.5 - 10.5

to

VERTICAL AMPLIFIER section of main-

response

the voltage

10

Table

by switching a

is

switched

cm

*5%

as

necessary.

4-1

lists the selector positions

off

(9.5 - 10.5

rms

cm).

0.1

and on the CRT

cm). Adjust

voltages which

-

A

VERT. SENSITIVITY to

“reference

A,

and monitor the input voltage with the

10

cm of deflection. Note reading on

oscillator” to input ter-

.01

VOLTS/CM

122A

If

not,

volt dc

off

and

I

d

1)

Set VERTICAL PRESENTATION to

A

VERT. SENSITIVITY to

A

VERT. SENSITIVITY VERNIER

TRIGGER LEVEL maximum counterdockwise

but not in AUTO.

Sensitivity

Volts/cm

.01

A

VOLTS/CM,(DC)

ro

Deflection Voltage Required

cm

.01

.1

1

10

CAL.

+

5% 5 5 5

5

4)

Set “reference oscillator” to

rmS

0.0

1767

0.1767

1.767

17.67

“reference

Set output to previous reading on The deflection should be at least down point).

section

If

not, refer toVERTICAL AMPLIFIER

of

maintenance procedure.

Peak/Peak

0.05

0.5

5.0

50.0

200

kilocycles.

7.07

vtvm”.

cm

(3db

4

Model 122A

Sect.

IV

Page

3

Repeat above procedure for channel B.

5)

VERTICAL AMPLIFIER COMMON

REJECTION

Set

A

VERT. SENSITIVITY to .01 VOLTS/CM

A

VERT. SENSITIVITY VERNIER to CAL. SWEEP TIME to VERT. PRESENTATION to TRIGGER LEVEL to AUTO. SYNC to INT

Connect the “reference oscillator” to the chan-

2) ne1

1

A

input terminal through an “adjustable atten-

tor”

Ual

3)

ma

of

4) int

Stl

cil

5)

of

E.

terminated with

With “reference oscillator’’ set to 1 kc and tximum output, switch in attenuation until deflection

Change input

o

both red input terminals. Remove ground .ap and connect ground side lator” to black terminal.

Switch “adjustable attenuator” until

1

cm

inge

least

at

Repeat above procedure for channel B.

VERTICAL AMPLIFIER COMMON-SIGNAL REJECTION (B-A)

is

displayed.

so

is

again obtained. The external attenuation

is

the common-signal rejection and should

40 db.

0.5

MILLISECONDS/CM

A

600

ohms.

that the same signal

of

\

-

“reference

a

deflection

SIGNAL

1

cm

is

fed

os-

6)

Switch A VERT. SENSITIVITY and B VERT.

SENSITIVITY to 0.1 VOLTS/CM. There should

less

than

10

cm of deflection.

7)

Switch VERT. PRESENTATION to B.

8)

Set the “reference oscillator” to 200 kc, and

5

adjust for

9)

Repeat steps 4, 5 and

as

before.

If the instrument

consult the appropriate part of the VERTICAL

AMPLIFIER section

F. WAL TRACE PRESENTATION

1) Set TRIGGER LEVEL to AUTO.

2) Adjust remaining oscilloscope controls to display the chopped

3)

The A VERT. chopped trace and move the other.

4) Set VERT. PRESENTATION to ALT. Thechan-

A

ne1 alternately.

cm of deflection.

Limits

6.

fails

to meet any

of

the maintenance procedure.

SYNC to INT VERT. PRESENTATION SWEEP TIME to A

VERT. SENSITIVITY to OFF

B VERT. SENSITIVITY to OFF

50

of

to

CHOP

MILLISECONDS/CM

trace.

POS

control should move one

B

VERT. POS control should

and channel B

traces

should

are

the same

these limits

be

displayed

be

b

1

A

VERT. SENSITIVITY

B

VERT. SENSITIVITY to B VERT. SENSITIVITY VERNIER to CAL. SWEEP TIME to VERT. PRESENTATION to B

Connect the “reference oscillator” to

2) tnnel

A

cha

Set “reference

3)

out

put for

Switch VERT. PRESENTATION

4) :tion should

flec

Set

5)

n

ti01

and channel B input terminals.

5

cm

A&

B VERT. SENSITIVITY to 1 V.

should

be

of

deflection.

be

less

0.5

oscillator”

than

to

10

VOLTS/CM

10

VOLTS/CM

MILLISECONDS/CM

to 2 kc and adjust

to

B-A.

than

0.1

cm.

1.0

cm.

both

the

De-

Deflec-

HORIZONTAL AMPLIFIER SENSITIVITY

G.

1) Set HORIZ SENS to HORIZ SENS VERNIER to CAL VERT PRESENTATION to

DC-AC (horizontal input coupling) to

2) Connect the “calibration generator”,

1.0

volts 4WPTP to the horizontal input terminals. Adjust the position controls to center the horizontal

(9.5-

AMPLIFIER section

3)

Check the dc response by switching dc voltage from the “calibration generator” and on. CRT “spot” should shift VERT. POS.

trace.

10.5

cm). If not,

As

the voltage

as

necessary.

.1

VOLTS/CM

A

The trace should

refer

of

the maintenance procedure.

is

switched

10

be

10

to the HORIZONTAL

off

and on, the

cm

*5%.

set

*5%

a

0.1

Adjust

DC

for

long

volt

off

A

Sect. IV Page

4)

Check the accuracy of the remaining VOLTS/CM

positions as given

Sensitivity

Volts/cm

.1

1

4

in

the

following table:

Voltage for 10 ( 5%) cm Deflection

Peak/Peak RMS

1.0 0.3535

10.0 3.535

Model 122A

vertical input.

~

with the

6)

7)

lator” until the pattern goes out of synchronization. The reading on

0.885 volts or

“reference

Set SYNC switch to EXT. Decrease the amplitude of the “reference oscil-

Monitor the

vtvm”.

the

“reference vtvm” should be

less.

sine

wave

amplitude

10

H.

HORIZONTAL AMPLIFIER BANDWIDTH

1) Set HORIZ SENS to TRIGGER LEVEL to AUTO

Connect the “reference oscillator” to the

2)

cilloscope horizontal input terminals. Monitor the

sine

3) Adjust the remaining oscilloscope controls

display the horizontal trace.

4)

Set the “reference oscillator” to 2 kilocycles and adjust for 10 cm on “reference vtvm”.

5) Set “reference oscillator” to Set output to previous reading on “reference vtvm”.

The deflection should now be at least down point).

AMPLIFIER section

I.

SWEEP GENERATOR TRIGGERING

1)

Set SYNC to INT

TRIGGER LEVEL to AUTO A A VERT PRESENTATION to

2) Connect the approximately 0.5 scope vertical input.

3)

Adjust remaining oscilloscope controls to dis-

play a

4)

lator” until the pattern The pattern should

5)

synchronization terminals and the oscilloscope

few

Decrease the input from the

Connect

I

100.0 35.35

I

.1

VOLTS/CM

os-

wave amplitude with the “reference vtvm”

of

deflection. Note reading

200

kilocycles.

7.07

cm (3 db

If

not,

refer

to the HORIZONTAL

of

the maintenance procedure.

VERT SENSITIVITY to VERT SENSITIVITY VERNIER to CAL

“reference

v

rms,

400

cycles of signal.

goes

be

0.5 cm high or

“reference

oscillator” to the external

0.1

VOLTS/CM

A

oscillator”, set for

cps, to the oscillo-

“reference

out of synchronization.

oscil-

less.

to

If the oscilloscope fails to meet either check, to the TRIGGER GENERATOR section of the maintenance procedure.

J.

INTERNAL SWEEP TIME

1

1)

.

2) Connect to the oscilloscope vertical input. Set “marker generator” for 1/1,000 sec of a period. display the signal to-peak deflection of signal should produce 10 cycles cm of horizontal deflection.

3)

checked using

step. Table 4-2 provides complete information on selector position, frequency or period of the timing signal and cycles of the signal produced in 9.5-10.5 cm of horizontal deflection. does not meet these checks, GENERATOR section of the maintenance procedure.

K.

1)

2)

to the oscilloscope vertical input. Set “marker

generator” for 1,00O/sec.

Ad just remaining oscilloscope controls to display

the

deflection of produce 10 cycles zontal deflection.

SWEEP TIME to

Set

SWEEP TIME VERNIER to CAL SYNC to INT TRIGGER LEVEL to AUTO

SWEEP EXPAND to

the

output of the “marker generator”

Adjust remaining oscilloscope controls to

with

a vertically centered peak-

4

Each step of the SWEEP TIME/CM selector

the

method outlined

EXPANDED SWEEP CALIBRATION

Set SWEEP TIME to 1 MILLISECONDS/CM

SWEEP TIME VERNIER to CAL. SYNC. to INT. TRIGGER LEVEL to AUTO. SWEEP EXPAND to

Connect

signal with a vertically centered peak-to-peak

the

output of the “marker generator”

4

to 6 centimeter. This signal should

in

10 (55%) centimeters of hori-

MILLISECONDS/CM

X1

1

millisecond

to 6 centimeters. This

in

10 *5% (9.5 - 10.5)

in

the previous

If

your oscilloscope

refer

to the TRIGGER

X1

or

a 1 millisecond period.

refer

is

Model

122A

Sect. IV Page

5

SWEEP TIME/CM

Position

*200

MILLISECONDS

100

MILLISECONDS

50

MILLISECONDS

20

MILLISECONDS

10

MILLISECONDS

5

MILLISECONDS

2

MILLISECONDS

1.

MILLISECONDS

.5

MILLISECONDS

200

MICROSECONDS

100

MICROSECONDS

50

MICROSECONDS

20

MICROSECONDS

TABLE

Frequency

1

10

10 10

100

100 100

1,OOO

1,000

1,OOO

10 10 10

4-2.

SWEEP TIME ACCURACY

Timing Signal

cycle

cycles cycles cycles

kilocycles kilocycles kilocycles

Period

1

second

100

milliseconds

100

milliseconds

100

milliseconds

10

milliseconds

10

milliseconds

10

milliseconds

1

millisecond

1

millisecond

1

millisecond

100

microseconds

100

microseconds

100

microseconds

Cycles Produced in

9.5

to

10.5

cm

2

10

5 2

10

5 2

10

5

2

10

5

2

10

MICROSECONDS

5

MICROSECONDS

*

Use

DC

input coupling

3)

Set SWEEP EXPAND switch

plete

cycles should now appear in

neters

4-3

Disconnect power cord and remove screws on the front panel

3ut

[f

moved, dangerous voltages

of

horizontal deflection.

REMOVING THE CABINET

rear

screws.

of

cabinet.

the instrument

is

to

avoid degrading input signal.

of

cabinet.

Slide oscilloscope forward

CAUTION

operated with the cabinet

are

100

to

X5.

10

Do

not remove any

exposed. Take

kilocycles kilocycles

Two

com-

(fig)

centi-

two

large

re-

10

microseconds

10

microseconds

adequate safety precautions, especially when working around the cathode-ray tube terminals and the

power

4-4

In many rected by replacing a weak

fore

ment, check the tubes. Adjustments that in an attempt will often complicate the

It rather than by use

supplies.

TUBE REPLACEMENT

cases

instrument malfunction can

changing the setting

to

compensate

is

good practice

to

of

check

a

10

5

or

defective tube. Be-

of

any internal adjust-

for a defective tube

repair

problem.

tubes

“tube

by substitution

checker”. The

be

are

cor-

made

Sect. IV Page 6

Model 122A

results obtained from the "tube misleading. Before removing that

if

the tube

same socket. Replace only tubes proved to be which should

weak or defective. replaced.

CIRCUIT

REFERENCE

I

4301 4302

is

good it can

TABLE 4-3.

v1

v2

v3

v4

v5

V6 v7 V8 v9 VlOl

v102 v201 v202 V203

V204 v205

V301

V302 V303

&

V304

V305

V306 V307

V308 V309

V310

checker"

a

tube, mark it

be

returned to the The following table lists the tests and adjustments

TUBE

TUBE OR TRANSISTOR TYPE

CTPl113 Regulator 2N383 Amplifier

12AU7 Vert. Input Amp. 12AU7 Vert. Amp.

6DJS/ECC88 Output Amp.

12AU7 Vert. Input Amp.

12AU7 Vert. Amp. 6DJ8/ECC88 Output Amp. 6DJ8/ECC88 Switching Amp. 12AU7 Switching Multivibrator 6AU6 Switching Amplifier 6DJ8/ECC88 Horiz. Amp.

12AT7 Output Amplifier

6AN8 Trigger Generator 6U8 Start-Stop Trigger

12AU7 Gate and Hold-off

12AU7 Integrator Switch

6U8 Sawtooth Integrator 12AU7 Amplifier 6AQ5 Oscillator 5642 5AQP- Cathode-Ray

12B4A Regulator 6U8 Amp.- Output

12B4A Regulator 6AU6 Amplifier 5651

AND

Cathode-Follower.

H.

V.

Cathode-Follower

Reference

can be Any tube with corresponding standard EIA (JEDEC)

so

&

TRANSISTOR REPLACEMENT CHART

FUNCTION

characteristics can

Check+ 24 volt power supply output. Same as 4301. Check Vertical Balance and Gain.

Same as Check Vertical Gain and Balance. Same as Same as Same as None. None. None. Entire Horiz. Amp. test procedure ex-

cept Attenuator Compensation. Same as V101. Check Trigger Generator. Check Sweep Stability Control Adj.

None.

Hum Balance.

None.

Check Same as V301.

Rectifier

Tube

Same as V301. See adjustments under

check Vert. and Horiz. Gain. Check +380 volt Check+380 and +lo0

Check -150 volt output voltage. Same as V308. Same as V308.

be

used as a replacement.

be

performed after the tubes are

TESTS

AND/OR

V1.

ADJUSTMENTS

V3.

H.

V.

Power Supply Output.

TURN

power

supply output.

v

output voltages.

ON

and

Model

122A

Sect.

IV Page

7

)

4-5

Ci

time

that

w:

is

imp any inti only

a

A.

CH:

-

All

ac

ments

cor

and

ti

If the

1)

Che of the usually Check

B. CHI

-

Check 4-9

PC

refer

tc

and

Ta

MENT

C. CHI

-

TROUBLE-SHOOTING PROCEDURE

1

del

122A Oscilloscope

isic

sections

an

be

minimized by following a procedure

ill

isolate

to

Irtant ernal adjustments. In the majorityof tube change

I

ECK AC POWER CIRCUIT

power

will

light with the instrument turned on

inected

ubes

will

ck the power line Ehassis. The cause

be

found in the

silicon

ECK

DC

dc voltages )WER SUPPLIES. If you replace any tubes

3

Table 4-3 TUBE REPLACEMENT CHART

ble 4-4 CONDENSED TEST AND ADJUST-

PROCEDURE.

ECK HIGH VOLTAGE CIRCUITS

or

the section needing

isolate the problem before changing

will

be

circuits

to

not light:

a

suitable

are

rectifiers,

LOW VOLTAGE CIRCUITS

as

described under paragraph

is

composed

circuits. Repair and

of

repair.

cases,

required.

normal if any tube

power

fuse

of

low

filter

source.

mounted on the

a

blown line fuse can

voltage power supply.

capacitors,

sev-

test

fila-

rear

etc.

The voltage on the cathode and grid can be most easily measured on the high voltage transformer assembly on the

top brace

be

removed on the cabinet model only).

It

vacuum tube voltmeter with a high voltage probe, such Voltage Multiplier Measure with the orange proximately -2250 volts. If the voltage value, both the Hartley Oscillator and the ondary connected be

assumed

Measure the CRT grid voltage by measuring the voltage on the green wire going

rectifier.

volts. If this voltage

the Hartley Oscillator and the secondary connected

to

the grid

If either Hartley Oscillator may ing properly. If neither voltage

for

the trouble in the Hartley Oscillator. If only one voltage cillator and that secondary erly. Look for trouble in the secondary supply with the incorrect voltage.

If you replace any

REPLACEMENT CHART and Table 4-4 CONDENSED TEST AND ADJUSTMENT PROCEDURE.

of

the instrument (shield

as

the @Model 410B VTVM with Model 459A

Probe,

this

voltage on the

wire.

to

the cathode

to

be

functioning properly.

This voltage should be -2260

is

are

functioning properly.

of

the above voltages

is

correct, both the Hartley

tubes

at

the

rectifier

will

for

this measurement.

rectifier

This voltage should be ap-

of

the CRT can

to

within these limits, both

are

be

assumed to be function-

is

present, look

are

functioning prop-

refer

to

Table 4-3 TUBE

of

the CRT

tubes

have

Use

terminal

is

of

the other

to

-2325

correct

to

a

this

sec-

the

Os-

If you focused control assume

If

a

sp

horizon ins ulatc TURN CONNE

be

foun

clip lea

This

s

the CR' control ray

tub

are able

I

spot with good brilliance by adjusting the

s,

d

to

ot

or

ita1 deflection plates

zd

INSTRUMENT OFF BEFORE MAKING THIS CTION. Terminals

id

in the

.d short

hould produce

T

screen

.

If not, check the voltage on the cathode-

e

cathode.

to

get a small, round, and sharply

the high voltage power supply can

be

working.

trace

is

clip

not present, short

lead.

circuit

at

DANGER HIGH VOLTAGE1

rear

access

the vertical deflection plates.

a

spot

some setting

of

the CRT with an

for

these plates

hatch. With a second

near the center

of

circuit

the INTENSITY

be

the

will

of

D.

CHECK HORIZONTAL

PLIFIERS

The Horizontal and tioning properly when CRT can be moved easily and smoothly by the horizontal and vertical position controls.

a

spot

is

If

1) Short the horizontal deflection plates together

with an insulated clip lead. DANGER HIGH VOLTAGE1 TURN THE INSTRUMENT MAKING THIS CONNECTION. Terminals plates

not visible on the screen:

are

accessible through the

Vertical

a

spot

AND

VERTICAL AM-

Amplifiers

on the

OFF

are

face

BEFORE

rear

for

access

func-

of

the

these

Sect. IV Page

8

Model 122A

hatch. If the “short” produces

be

moved by VERT POS

by

a

vertical input, the vertical amplifier

functioning properly.

2) Short the vertical deflection plates together. If this produces HORIZ POS control and deflected by input, the horizontal amplifier

properly.

amplifiers

The and balanced, and corresponding voltages in each side

of

the

circuit

the spot on the screen. The settings balance and position controls balanced voltages and should checking an amplifier.

To

check an inoperative amplifier, short

cuit

corresponding points in each

at

ing the spot does not return to the screen. ample, in the Horizontal Amplifier, is connected together, remove the jumper from tween the deflection plates and connect it between the plate (pin V102A). Work toward the input, shorting gridto-grid, and plate-to-plate until

where the spot

will

appeared and the point where the spot no longer appears.

E.

the CRT, until a point

on the screen when the deflection plates

be

between the last point where the

CHECK SWEEP GENERATORS

a

in the instrument

must remain balanced to keep

6)

of

V102B and the plate (pin

does

control

spot that can

not appear. The trouble

a

spot

and deflected

be

moved by

a

horizontal

is

functioning

are

direct

coupled

can

introduce un-

be

considered when

stage,

is

reached where

For

if

the spot

a

point

is

reached

that

of

gain,

start-

spot

can

is

cir-

ex-

are

be-

1

of

2)

A

repetitive sweep should

of

position the generator

step

in the order listed.

Turn the ling the voltages indicated point with an @Model pedance Vacuum Tube Voltmeter.

3)

Check

by substitution. Always replace the original

if

proper operation

4) Check the setting by rotating the control through the entire adjustment range.

If the

a.

plete adjustment step

If adjustment does not restore operation,

b.

R228 near the mechanical center ment range.

Check the setting

5)

Rotate the control through the entire adjustment range.

the SWEEP TIME/CM

is

inoperative, try

NOTE

-

power

tubes

are

tubes

generator

off

before

discussed in this procedure.

measured between ground and the

V201 through V205, one

is

not

of

Stability Adjustment, R228,

operates at some setting, com-

10,

of

be

obtained in each

selector.

the

following

removing

410B

or

High Im-

at

restored.

describedinTable4-4.

of

the adjust-

Trigger

Sensitivity R247.

instal-

All

a

time

tube

set

If

I

1)

Set A VERT SENSITIVITY

B

VERT SENSITIVITY

VERT. PRESENTATION to SWEEP EXPAND

SYNC

to

INT

TRIGGER LEVEL

to

X1

AUTO

OFF

A

.’

If the generator operates at some setting, com-

a.

plete adjustment step

If adjustment does not

b.

R247 near the mechanical center ment range.

9,

described inTable 4-4.

restore

operation, set

of

the adjust-

del

122A

6

CONDENSED TEST AND ADJUSTMENT PROCEDURE

the basic

test

and adjustments

are

covered

in the following Table

for

instruments that

strument

is

not operating

are

4-4.

This procedure

functioning.

refer

to

Sect.

IV

If

paragraph

Page

is

the in-

4-5.

9

EQUIPMENT

REQUIRED

Dc

vtvm with

1%

accuracy.

None

400 cycle Voltage Calibration Generator

None

~~

None

400 cycle Voltage Calibration Generator

Time Marker Generator

Oscilloscope with low capacity probe

PROCEDURE

Measure all low voltage power supply outputs, should be within the following

limits: -150+2 volts

+100*3 volts +380*10 volts

+

24

k1

volt

A.

VERT. SENSITIVITY to .01,

VERNIER fully ccw.

B VERT. SENSITIVITY to OFF HORIZ. SENS. to 10 VOLTS/CM

Rotate VERNIER fully

A

VERT. SENSITIVITY to .01,

cw

VERNIER to CAL VERT. PRESENTATION to

A

Connect 100 mv p-p from Calibration Generator to

B

VERT. SENSITIVITY to .01,

(A)

vertical amplifier.

VERNIER to CAL VERT. PRESENTATION to B Connect 100 mv p-p from Calibration Generator to (B) vertical amplifier.

A

VERT. SENSITIVITY

in

CAL B VERT. SENSITIVITY in CAL and both VERNIER’S in CAL.

HORIZ SENS to 10 VOLTS/CM, VERNIER to CAL.,

A

VERT. SENSITIVITY to OFF,

VERT. PRESENTATION to

A.

Turn VERNIER fully ccw.

.1

HORIZ SENS to

VOLTS/CM,

VERNIER to CAL.,

A

VERT. SENS. to OFF,

VERT. PRESENTATION to

A.

Connect 1.0 v p-p from Calibration Generator to horizontal input.

5

SWEEP TIME to SWEEP EXPAND to

MILLISECONDS/CM,

X1.

Apply 5 millisecond markers to vertical input.

Change time markers to

1

MILLISECONDS/

CM and set SWEEP EXPAND to X5.

SWEEP TIME 10 psec/cm., SWEEP EXPAND to

X1

Connect probe to pin 1 or 6 of V102. Adjust sweep start to center of screen. SWEEP EXPAND to X5. Adjust Sweep-

Start to center of

screen.

Do

not adjust

ADJUST

if

within limits. Check sweep

-

NOTES

Adjust R344 for -150 volts. calibration

-150~ (R268)

is

adjusted.

Adjust spot to center of

screen

with A VERTICAL required.

Repeat as

POSITION control.

Repeat for

Center spot with channel

A

BAL.

A

Adjust channel

Gain (R27)

channel

B.

for 10 cm deflection.

Adjust channel B

Gain

(R47)

for 10 cm deflection.

Adjust Calibrator Set (R356) for 6.0 cm deflection.

A

Center spot with

(outer) Repeat as

VERT. POS. knob. required.

Center spot with Horiz. Bal.

(R110).

-

Set Horiz. Gain (R114) for

10 cm horiz. deflection.

Adjust trigger level for stable pattern. Adjust R107 for marker coincidence with

1

cm graticule

marks. Adjust R108 for marker coin-

cidence with

1

cm graticule

marks. Adjust C105 to compensate

fly bac

k.

Adjust C106 to compensate flyback.

if

Oscilloscope with

1O:l

probe

50

cps to 250 kc

oscillator AC VTVM

DC

VTVM

SYNC to EXT., TRIGGER LEVEL to AUTO.

DC

couple a 250 kc

sine

wave of

.5

v rms

into the EXT. SYNC. input.

to

Couple probe loosely

body of R204

(a 3.6K resistor pin 6 V201) Disconnect

(-100

all

ext. inputs. Connect VTVM

v

scale) to pin

8

of

V203, VERT. SENS. to OFF SWEEP TIME to

.5

MILLISECONDS/CM, SYNC INT. TRIGGER LEVEL fully ccw but not in AUTO.

Set trigger sensitivity control Check for stab1 (R247) just clockwise of

the

point where stable triggers

are

obtained.

triggers from

50

cps to 250

with

0.5

v

rms.

kc

Slowly adjust SWEEP STABIL-

until

sweep

ITY (R228)

begins. Repeat and note voltage just prior to sweep start. Set R228 for 2.0 volts more positive.

M

o(

jel

122A

Sect. IV Page

11

4-1

usu

con

test

con

The mer

tion

cau, befc mer

SPE CIL MA: COT

AL'

EX' CAI

For

low:

VOll

seci SUP1

recc

adjL

4-a

Per

has of

SUP1

rhpi

-..-:k upon the correctness have been made.

1) to ground. When measured with an @Model 410B

Voltmeter, they should be within

COMPLETE ADJUSTMENT PROCEDURE

ially a particular oscilloscope will not need

or

iplete testing and calibration. Only one

:s

will be needed and they can be done without

ipleting the entire

!

following procedures

ided sequence

I

operation. In general, tubes

se

of trouble and new ones should be tried

ire

making adjustments

its. See paragraph 4-4. 3CIFICATIONS FOR THE

,LOSCOPE ARE GIVEN IN THE FRONT OF THIS NUAL. THE FOLLOWING TEST PROCEDURE gTAINS EXTRA CHECKS TO HELP YOU fZE A PARTICULAR INSTRUMENT. THESE TRA CHECKS AND THE DATA THEY CONTAIN VNOT BE CONSIDERED AS SPECIFICATIONS.

'

location ing procedure, tage tion. A fifteen minute warm-up and power ply output voltage measurements 2mmended before making any other

is

tment

TURN

form this procedure only after repair work

been done on the instrument. The purpose

lis

procedure

tl

Jlies

Measure resistances from the power supplies

of

and Resistance Diagram

.

ON

have been shorted and

test

procedure.

are

listed in a recom-

for a complete

test

and calibra-

are

or

component replace-

@

MODEL 122A

the controls mentioned in the fol-

see

Figures 4-1, 4-2 and the

at

the end of this

are

PROCEDURE

is

to

check that none

to

of

50%

of

the power

serve

as

the repairs that

of the following:

two

the main

OS-

AN-

always

test

a

partial

or

3)

Turn instrument on and measure the output voltage of the internal graph 4-9 POWER SUPPLIES). When turning the oscilloscope on for the

power supply circuit, turn the INTENSITY control

fully counterclockwise before applying power. ure to follow this precaution may cause permanent cathode-ray tube damage. If you

a

small, round, and sharply focused spot with good

brilliance by adjusting the controls, the high voltage

power supply can be assumed properly.

4) If necessary, the high voltage can be measured and adjusted

Voltage Adjustment, Astigmatism (R316) controls tain

a

small, round, and sharply focused spot. If the high voltage and Horizontal Amplifier Gain.

5)

If the cathode-ray tube physical position has been changed, check Turn TRIGGER LEVEL control fully counterclockwise

to

CROSECONDS/CM. The CRT

parallel with the graticule lines. The CRT should be placed just behind the If CRT face and pattern will result.

4-9

The power supplies in the oscilloscope

tremely stable and will require infrequent adjust-

ment. The output voltages should be measured with an @Model 405A but unnecessary adjustments should be avoided.

POWER SUPPLIES

a

as

in paragraph 4-8. If R308, High

is

AUTO. Set SWEEP TIME switch to

filter

recently calibrated

power

first

is

changed, adjust FOCUS and

changed, recalibrate the

trace

touch, a visible interference

or

412A, at regular intervals

supplies (see para-

time

after

repair in any

Fail-

are

able to

to

be operating

at

low

intensity toob-

Vertical

alignment with bezel.

50

MI-

trace

should be

face

filter

in the bezel.

are

ex-

1%

voltmeter, such

get

as

50K

+

380

volt supply

+

100

-150 12K

+

24 5.5K (Remove V1, 2,

2) Measure resistances

and horizontal input terminals positions. As Voltmeter these resistances should

VERT SENSITIVITY

HORIZ SENSITIVITY I 1

measured with an @Model 410B

to

OFF

CAL

ohms

50K

4, and

ground into the vertical

for

=

1

Megohm

=a

=a,

Megohm

all

read:

5

to check)

dc switch

CAUTION

When first turning the oscilloscope on turn the INTENSITY control fully counterclockwise before applying power. Failure can cause permanent cathode-ray tube damage.

to

follow this precaution

------------

1) Turn instrument on and allow at'least 15 minutes for warm-up.

2) Turn the sweep generator off by turning the SWEEP TIME

CM.

-

HORIZ SENS switch

to

10

VOLTS/

Sect.

IV

Page

12

Model 122A

3) Measure power supply output voltages with line

set

to

115

voltage various voltages appear can

color

wire will normally tiometer Low Voltage Set, R344, can if necessary, the limits in Table 4-5. If the voltages limits and adjust in an attempt settings.

If adjustment of the check ments.

TABLE 4-5. REGULATED POWER SUPPLY

NOMINAL NORMAL VOLTAGE

-7-

code

pass

all

Sweep Generator and Calibrator adjust-

RIPPLE

-150

+

380

+

100

+

24

With line voltage

c*

In vertical amplifiers.

40

v. The points at which the

be

identified by the

given in Table 4-5. The voltages

be

within the limits given. Poten-

be

adjusted,

to

set the

-150

volt supply within

are

steps 4 and 5 that follow,

to

refine the existing control

-150

4

3

mv

set

to

volt supply

COLOR

CODE

Violet

Red

Yellow

White**

115

v.

is

necessary,

VOLTAGE

TOLERANCE*

*

2 volts

*lo

*3

*

1

within do

not

spot. and adjust Intensity Limit control, R322, the CRT ments the high voltage control, R308, has been changed.

4-10

The Trigger Generator must the Vertical and Horizontal Amplifiers. Also, these amplifiers must be adjusted before the Sawtooth Generator can be adjusted. Check the Generator

1) Check power supply according

2) Adjust Stability Control, R228.

Connect an @410B (-100 v dc range) V203. Slowly counterclockwise until the sweep ning. Then back control

Take

-78

the the stability control.

Set

pointer on INTENSITY knob

spot

is

just extinguished. These adjust-

are

usually required only

TRIGGER GENERATOR

as

follows:

Set A VERT SENSITIVITY

B VERT SENSITIVITY

SWEEP TIME SYNC to INT TRIGGER

not in AUTO.

VERT PRESENTATION to A

to

LEVEL

rotate

.5

fully counterclockwise but

Stability Control, R228,

if

the setting

be

working to adjust

to

paragraph 4-9.

to

OFF

to

OFF

MILLISECONDS/CM

or

starts

off

until

it

a

voltage reading which should be about

Set

volts.

last

R228 to 2.0 volts more positive than

reading. This

is

the proper setting for

to 9 o’clock

so

that

Trigger

B

to

pin 8

free-run-

just stops.

of

4) You may wish supply voltage between

should remain within range.

5) Measure the ripple voltage on the various sup-

plies. They should approximate the values given

in

6) Measure instructed in paragraph 4-5C.

H.

voltage to -2250 volts. If this adjustment changed, amplifier gain.

7)

ASTIGMATISM control, R316, for a small, round,

103

Table

V, Adjustment, can

Adjust FOCUS control

4-5 with the line voltage

recalibrate

to

check regulation of each power

as

the power line voltage

and

127

volts. All regulated voltages

*l%

over this line voltage

cathode-ray tube cathode voltage

If necessary R308,

be

adjusted to

the horizontal and vertical

for

best focus and

at

fs

115

set

varied

volts.

as

this

is

set

3) External

Set

Trigger

SYNC switch TRIGGER LEVEL Horizontal AC-DC switch VERT PRESENTATION control

Trigger

counterclockwise.

Connect SYNC (right-hand) terminals. observe the probe over the body

Increase Trigger Sensitivity

stable

tivity from should

range. when the TRIGGER LEVEL control position--should

a

250 kc sine wave of

square

triggers

50

be

obtained with

Remove the test set-up and check the

Sensitivity

to

EXT

to

AUTO

to

DC

Sensitivity Control, R247, fully

0.7

With an oscilloscope

wave by clipping the oscilloscope

of

R204 (V201A plate resistor).

control R247, until

are

obtained.

cps to 250 kc. Stable triggering

less

be

about 120

Check

than 0.7 v rms over this

*50

cps.

to

A

or

v rms to the

trigger

sensi-

rate

is

in AUTO

B

Sect. IV Page

13

Figure

4-11

1)

Turn

counterclockwise and adjust spot to center with A

VERNIER control fully clockwise and readjust spot

to

until there

is

ter.

2)

VERTICAL AMPLIFIER

Balance Channel

Set VERT PRESENTATION

A

VERT SENSITIVITY

HORIZ. SENSITIVITY A

VERT. SENSITIVITY VERNIER fully VERT. center with BAL control. Repeat this sequence rotated. Set A VERT.

Balance Channel B

Set VERT. PRESENTATION

POS.

is

Spot should now be on screen.

B VERT. SENSITIVITY HORIZ. SENS.

A

to

control. Turn A SENSITIVITY

no movement

of

POS.

control

to

10

VOLTS/CM

Left-Side Adjustment Location Diagram

4-1.

A

.01

VOLTS/CM

10

VOLTS/CM

spot

as

VERNIER

to

the cen-

B

to

10

VOLTS/CM

MP-S-408

Using B VERT. SENSITIVITY VERNIER and VERT.

3)

Feed into channel volt peak-to-peak signal from tion Generator

of

Check this setting

Setting voltages. If not, check power supplies and vertical amplifier tubes.

4)

POS.

control repeat procedure

Adjust Channel A Gain Set VERT. PRESENTATION

A

VERT. SENSITIVITY

A

VERT. SENSITIVITY VERNIER to CAL

A

input terminals

(($9

Specification

channel

Adjust Channel B Gain

Set VERT. PRESENTATION

A

to

give exactly

at

127

and

of

GAIN control should

VERT. SENSITIVITY VERNIER

B

of

step

to

A

to

.01

VOLTS/CM

a

100

milli-

a

Voltmeter Calibra-

23678).

10

cm

103

volts line input.

be

to

B

Set GAIN

of

deflection.

same with

to

CAL

all

B

1.

Sect. IV Page 14

of

Repeat procedure

controls.

and

5)

Channel B Attenuator Compensation

B VERT. SENSITIVITY to

Set

(E

B VERT. SENSITIVITY VERNIER

SYNC

to

TRIGGER LEVEL

SWEEP TIME VERT. PRESENTATION

Connect

minals. Adjust flection. Adjust C13

uator

VERT. SENSITIVITY input response. VOLTS/CM and apply

generator

Switch back through the

and check

5

kc square wave

for

a

flat-topped square wave. Switch

to

give

8 cm deflection. Adjust C16

Switch

to

input. Adjust C18

for

1O:l

step 3 with channel B input

range)

INT

+

to

AUTO.

to

200 $EC/CM

to

channel

level

for

an 8 cm verticalde-

on

channel B vertical atten-

to

1

VOLTS/CM and increase

B

VERT. SENSITIVITY

full

output

four

attenuator pitions

divisions

(should

.1

VOLTS/CM

to

B

B input

of

square wave

for

flat

be

within

to

CAL

ter-

for

flat

to

response.

1%).

B

10

Model 122A

6)

Channel A Attenuator Compensation

Set

A

VERT. SENSITIVITY to

(DC

range)

A

VERT. SENSITIVITY VERNIER

SYNC

to

DIT+

TRIGGER LEVEL to AUTO. SWEEP TIME

B

VERT. SENSITIVITY

(DC

range)

B

VERT. SENSITIVITY VERNIER

a

200

Apply channel

erence PRESENTATION to B-A and adjust C3 attenuator VERT. SENSITIVITY and B VERT. SENSITIVITY

to

deflection.

Set

SENSITIVITY

a

oscillator"

10

VOLTS/CM and adjust C8

VERT. PRESENTATION to A and A VERT

5

kc

kc sine wave

B

vertical

for

to

square wave

to

200 pSEC/CM

to

input terminals

set

for

20-25 volts. Set VERT.

minimum deflection. Set both

.1

VOLTS/CM

to

channel A input and adjust

.1

VOLTS/CM

to

CAL

to

.1

VOLTS/CM

to

CAL

both channel A and

from

a

"ref-

on

channel

for

minimum

(DC

range). Apply

A A

C223

C235

C233

C225

C226

L

..

Figure 4-2. Right-Side Adjustment Location Diagram

Model 122A Sect. IV Page

level

for

8

cm deflection. Adjust C22 on VERT

PRESENTATION switch for flat response.

7) Calibrator Amplitude NOTE

Channel this step.

A

gain should be adjusted

before

doing

------------

Set A VERT SENSITIVITY to CAL

A

VERT SENSITIVITY VERNIER B VERT SENSITIVITY B VERT SENSITIVITY VERNIER VERT PRESENTATION to

TRIGGER LEVEL to AUTO

Adjust Calibrator Set, vertical deflection.

4-12

1)

Adjust control. Turn HORIZ SENS VERNIER fully counter clockwise and readjust position ontal Balance Adjustment, R110. Turn HORIZ SENS VERNIER HORIZ POS control. Repeat until there movement

is

The

2) Adjust GAIN

Apply bration Generator (@Specification 23678) horizontal input terminals. Set Horiz. Gain Ad-

justment, R114, Check this setting

Setting voltages. If not, check power supplies and horizontal amplifier

HORIZONTAL

Balance

Set HORIZ SENS switch to

HORIZ SENS VERNIER B VERT SENSITIVITY VERT PRESENTATION

spot

to

of

spot when HORIZ SENS VERNIER

rotated. Set HORIZ POS control

spot

should now be on screen.

Set HORlZ. SENS. control

HORIZ. SENS. VERNIER

1.0

v peak-to-peak from a Voltmeter

of

GAIN control should

center

to

for

at

AMPUFIER

of

CAL and center

exactly

high and low line voltages.

tubes.

to

CAL

A

R365,

for

exactly 6 cm

ADJUSTMENTS

10

to

CAL

to

OFF

to

B

screen with HORIZ POS

of

spot with Horiz-

to

.1

to

CAL

10

cm

of

be

to

CAL

to

CAL

VOLTS/CM

spot

with

is

to

center.

VOLTS/CM

Cali-

to

deflection.

same at

no

the

all

3)

Square Wave Response Set HORIZ. SENS.

HORIZ. SENS. VERNIER VERT. PRESENTATION

Connect “square wave generator” vertical input terminals. Apply

to

horizontal input terminals and

to

trigger Sawtooth Generator. Adjust C107

minimum capacity. Adjust CllO

A

wave.

4)

Attenuator Compensation Set HORIZ. SENS.

Apply minals and

of

tooth Generator connected minals. Adjust C233 on SWEEP TIME switch flat response. Switch HORIZ. SENS. switch

10

VOLTS/CM and adjust C233 Now switch back through the three attenuator ranges and check within

5)

Phase Adjustment

Set HORIZ. SENS.

Apply channel B input terminals, and input terminals. Adjust amplitude

6

cm

PRESENTATION

of

pattern.

and adjust C44

phase adjustment on

CM ranges

4-13

The

adjusted

be

completed.

1)

X1

Set SWEEP TIME switch

maximum

HORIZ. SENS. VERNIER

5

kc square wave to horizontal input ter-

also

for

1%.

HORIZ. SENS. VERNIER A

VERT. SENSITIVITY to

A

VERT. SENSITIVlTY VERNIER B VERT. SENSITIVITY B VERT. SENSITIVITY VERNIER to CAL

VERT. PRESENTATION

100

kc sine wave

of

deflection along both axes. Switch VERT.

Switch VERT. PRESENTATION

also.

SWEEP GENERATOR

Vertical and Horizontal amplifiers must

before

Calibration

CM

SWEEP EXPAND switch

to

.l

VOLTS/CM

to

CAL

to

B

to

50

kc square wave

use

for

optimum square

of

2% overshoot

to

1

VOLTS/CM

use same signal

to

1O:l

division. Division should

to

.1

VOLTS/CM

is

to

CAL

to

trigger a Saw-

vertical input

for

flat

to

CAL

.1

to

.1

to

A

to

both channel A and

to

the horizontal

to

B and adjust C107

for

closure

.1

Sweep Generator Adjustment can

of

pattern.

VOLTS/CM and 1 VOLT/

to

5

MILLISECONDS/

to

X1

channel B

same signal

permitted.

response.

VOLTS/CM

to

VOLTS/CM

give about

for

closure

Check

15

for

ter-

for

to

be

CAL

to

A

be

Sect.

IV

Page 16

Model 122A

Apply 100 cps from to Vertical Input terminals. Adjust TRIGGER LEVEL control and choose either INT+ or best pattern. R107, other major division on

2) X5 Calibration

Apply input terminals. Adjust TRIGGER LEVEL control for R108, major division on the graticule.

3) Sweep Attenuator Compensation Set SWEEP TIME switch to

Set C226 (see Figure 4-2) to mid-value. 50:l probe to the calibrator output of an additional, monitor, oscilloscope. Compensate the probe.

Attach this probe to pin 2 of at input to Horizontal Amplifier. Apply marker pips from a “Marker Generator” to the Vertical input terminals. Adjust C214 ure of sawtooth. The flyback should not overshoot

or

4)

Connect 50:l probe to output of Horizohtal Amplifier, pin sweep to center of screen with HORIZ. POS. control. pensation of fly-back of sawtooth. Switch SWEEP EXPAND switch to X5 and adjust C106

ure

5) Calibrate

so

Set SWEEP EXPAND switch X5

1

kc from “Marker Generator” to Vertical

best

pattern.

so

SWEEP EXPAND switch to

4-4

undershoot the steady-state voltage.

X1

-

X5 Compensation

Set SWEEP EXPAND switch to

4-3) for proper compensation.

Set SdEEP TIME to 50 MILLISECONDS/CM

Adjust

that the markers coincide with every

that the markers coincide with each

in

this

1

or 6 of V102. Position start of

Adjust C105 (see Figure 4-3) for com-

50

a

Time Marker Generator

for

-

X1

Sweep Gain Adjustment,

the

graticule.

Adjust X5 Sweep Gain Adjustment

10

MICROSECONDS/CM

X1

Attach

VlOlA

section)

millisecond Adjustment Control

to

view

sawtooth

100

kc

(see

Fig-

compensate fly-back

X1

(see

Fig-

Remove probe.

Apply minals. for marker coincidence with every other major division on the graticule.

6) Calibrate 0.5 millisecond Adjustment Control

Apply

terminals. Adjust C223 coincidence with graticule.

7) Calibrate 50 MICROSECONDS/CM Adjustment

Apply terminals. Adjust C225 (see Figure 4-2) for marker coincidence

graticule.

8)

Apply

Vertical input terminals. Adjust C226

ure

major division on the graticule.

9)

Apply 1 kc to the Vertical input terminals. Turn the SWEEP TIME VERNIER down approximately 3:l and tune to observe hum modulation on thesweep. Switch SWEEP EXPAND switch to X5. Adjust Hum ance control, R360, for minimum hum.

10

cps time markers to Vertical input ter-

Adjust

Set SWEEP SPEED to

1

kc time markers to the Vertical input

Control

Set SWEEP SPEED control to 50 MICROSEC-

ONDS/CM

10

Calibrate 5 MICROSECONDS/CM Adjustment Control

Set SWEEP SPEED switch to

ONDS/CM

100

4-2) for marker coincidence with every other

Hum Set SWEEP TIME switch to .5 MILLISECOND/

SYNC to TRIGGER LEVEL control to AUTO SWEEP EXPAND switch

50

ms Calibrate adjustment, R251,

.5

MILLISECONDS/CM

(see

Figure 4-2) for marker

every

other major marker on the

kc time markers to the Vertical input

with

every

other major division on

5

MICROSEC-

kc from “Marker Generator” to the

CM

(see

the

Fig-

INT

to

X1

sine

wave

from “reference oscillator”

Bal-

Sect.

IV

Page

18

Model

'.

\

122A

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c

.-

L

c

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W

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Model

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Sect.

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Page

19

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Page

20

Model

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Page

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INTERNATIONAL

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CORPORATION

CR30

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953

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1000

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REF. DESIGNATORS

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CATHODE RAY TUBE WARRANTY

The cathode ray tube supplied in your Hewlett-Packard Oscilloscope and replacement cathode ray tubes purchased from

date

of sale

not included in

Your

local Hewlett-Packard representative maintains a stock

glad to process your warranty claim for you.

Whenever out in

rival, since

by

the

Hewlett-Packard Company. Broken tubes

this

guarantee.

a

tube

is

returned for a warranty claim,

full

and returned with

no

credit can

1)

Carefully wrap the tube in

padding material.

2)

Wrap

the

3)

Pack in a rigid container which

the

tube in each dimension.

@

,

are guaranteed against electrical failure for one year from the

the

tube. Follow shipping instructions carefullyto insure safe

be

allowed on broken tubes.

SHIPPING INSTRUCTIONS

1/4"

above in heavy

kraft

Please

thick cotton batting

paper.

is

at

the

least

consult him.

reverse

4

inches larger than

or

tubes with burned phosphor

of

replacement tubes and will be

side

of

this

sheet

must

or

other soft

be

are

filled

ar-

4)

Surround

similar shockabsorbing material. tight

5)

Tubes

be

packed in a wooden box.

6)

Ship prepaid preferably by

We

HEWLETT-PACKARD CO.

the

all

around

returned from outside the continental United

do

not recommend parcel post

tube withat

the

275

PAGE MILL ROAD, PAL0 ALTO, CALIF. U.S.A.

tube.

least

four inches ofpackedexcelsior

Be

certain

AIR

FREIGHTor RAILWAY

or

air

that

parcel post shipment.

the packing

States

should

EXPRESS.

or

is

CRT WARRANTY CLAIM

FROM: DATE: NAME COMPANY:

Person to contact for further information:

TITLE

COMPANY:

ADDRESS:

To process your claim quickly please enter the information indicated below:

1)

2)

3)

:

($3

INSTRUMENT MODEL SERIAL

TUBE TYPE SERIAL

OFUGINALTUBE REPLACEMENT TUBE

4)

YOUR PURCHASE ORDER NO.

5)

DATE PURCHASED

6)

PURCHASED FROM

7)

COMPLAINT: (Please describe nature of trouble)

8)

OPERATING CONDITIONS: (Please describe conditions prior to and

SIGNATURE

at

time of failure

-

Sect.V Page

1

TABLE

in this instrument, whenever possible. However, special

components may be obtained from your local Hewlett-

or

Packard representative

When ordering parts always include:

from the factory.

OF

REPLACEABLE PARTS

SECTION

V

1.

63

Stock Number.

2.

Complete description of part including circuit reference.

3.

Model number and strument.

4.

If

part

tion, function, and location of part.

If

there are any corrections for the Table of Replaceable

Parts

sheet

they

at

the front

is

not listed give complete descrip-

will

be listed on an Instruction Manual Change

of

this manual.

serial

number

of

in-

Sect. V Page 2

CIRCUlT

REF.

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

*

&

MFR.

DESIGNATION

@

STOCl

NO.

Model 122A

-

#

c1

c2

c3

c4

c5

C6

c7

C8

c9

c10

Capacitor: fixed, mylar,

0.1 pf *2%, 600 vdcw

Capacitor: fixed, mica,

27 ppf *5%, 300 vdcw

Capacitor: variable, ceramic,

5-25 ppf

Capacitor: fixed, mica,

390 ppf

Capacitor: fixed, mica,

15 ppf

Same

Capacitor: fixed, mica,

3300 ppf

Capacitor: variable, polystyrene,

0.7 - 3 ppf, 350 vdcw

Capacitor: fixed, ceramic,

.002 pf *2Wo,

Capacitor: fixed, ceramic,

.

01

~100/0,

*lo%,

as

C3

pf *20%,250 vdcw

500 VdCW

500 vdcw

*lo%,

1000

500

vdcw

Texas Capacitor Co.

16-110

14-78

Z"

13-28

14-65

14-15

14-64

V*

13-37

L*

15-80

L*

15-135

cw4

c11

c

12

C13

C14

C15

C 16

C17

C 18

*

See

#

Total qua

Lid

game

as

C1

3ame

as

C2

as

used

C3

C4

C5

C3

C7

C8

in

the instrument.

Same

If

Manufacturers Code Letters

ity

For

Replaceable

Pa

s

Table".

C"..

le1

IRCUIT

C

REF.

9

c1

122

TABLE OF REPLACEABLE PARTS

r

DESCRIPTION, MFR.

Same as C9

~

_____~

*

i%

MFR. DESIGNATION

@

STOCI

NO.

-

Sect.

V

Page 3

#

Ma

-

c2

c

2,

c

21

c21

c

2!

c3

c3:

0

1

2

3A

4,25

6,27

B

9,30

1,32

3,34

Same

as

C10

Capacitor: fixed, mica,

5

wf

*2Wo, 500 vdcw

Capacitor: variable, ceramic,

3

-

12

wf

Capacitor: fixed, electrolytic, 2 sections,

120

If,

40

pf,

450 vdcw

Capacitor: fixed, titanium dioxide,

2.0

wf

*5%,

500 vdcw

Same

as

C7

Capacitor: fixed, ceramic,

.01

pf,

tol.

-0%

+1Ooo/o,

Capacitor: fixed, titanium dioxide,

1.5

ppf

Same

as

*2W0,

C24

C7

500

1000 VdCW

Vdcw

V*

L*

cc

DD*

cc*

DD*

*

14-68

13-29

18

-

51HP

15-118

15-43

15-38

2

1

2

3

13

4

c31

c

c31

C3!

c41

c4:

-

*

#

3(

St

TI

5

;,

37

3

J,40

1,42

?e

tal

"Lis1

Same

as

C28

as

22

330

C29

as

C28

as

C5

ppf

*50/0, 500 vdcw

ppf

*lo%,

in

the

500 vdcw

instrument.

Same

Zapacitor: fixed, mica,

3f Manufacturers Code Letters

quantity used

For

ReDlaceable

J*

Z*

Pa

15-116

14-79

:s

Table".

2

-

Sect. V Page

CIRCUIT

REF.

~~

4

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

*

&

MFR.

DESIGNATION

@

STOCl

NO.

-

#

Model

122A

c44

c45

thru

C46

c

100

ClOl

c102

C103

C 104

C105

C106

C107

Capacitor: variable, mica,

2 - 25

Same as

These circuit references

not assigned

Capacitor: fixed, paper,

0.1

Capacitor: fixed, titanium dioxide,

2.2

Same as

Capacitor: variable, mica,

50 - 380

Same as

Wf,

C21

pf

*100/0, 600

ppf

*lo%, 500

C28

C102

C44

ppf,

C3

175

VdCW

vdcw

QQ*

cc*

DD*

QQ*

13-34

16-1

15-52

13-5

4

2

3

2

C108,109

CllO

Clll

2112

:113

thru

2199 2200

:201

See

11

List

#

Total

quantity used in the instrument.

Same as

Capacitor: fixed, mica,

iame as

rhese circuit references

Japacitor: fixed, mica,

Japacitor: fixed,

of

Manufacturers Code Letters For ReDlaceable

C102

C106

680

Wf

*100/~,

C28

not assigned

33

ppf

*5%, 300

1.0

wf'fl%,

500

V~CW

vdcw

titanium

500

vdcw

*'

dioxide,

Z*

DD*

Pa

14-21

5-136

5-102

6

Tablerr.

1

2

1

-

Model 122A

~~

CIRCUrr

REF.

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

*

&

MFR. DESIGNATION

@

STOCE

NO.

-

Sect.

V

Page 5

#

c202

C203

C204

C205,206

C207

C208

C209

c210

c211

Capacitor: fixed, paper,

ppf

as

*lm,

C200

*lo%,

+lo%,

*lo%,

220

Same

Capacitor: fixed, mica,

22 ppf *5%, 500 vdcw

Capacitor: fixed, electrolytic,

20 pf, 25 vdcw

Capacitor: fixed,

68 ppf

This circuit reference

not assigned

Capacitor: fixed,

2000 ppf *20%, 1000 vdcw

Capacitor: fixed, mica,

100 ppf

Capacitor: fixed, mica,

100 ppf

600 vdcw

mica,

500 vdcw

ceramic,

500 vdcw

500

vdcw

Radio Materials Corp.

cc*

V*

cc*

V*

16-12

14-69

18-66

14-60

15-80

14-73

14-100

1

2

1

c212

C213

C214

C215 C216

C217

C218

C219,220

*

See

#

Total

Same

as

C28

Capacitor: fixed, mica,

820

ppf

*lo%,

Capacitor: variable, mica,

-

150 ppf, 175 VdCW

14

Same

as

C28

This circuit reference

not assigned

Capacitor: fixed, mica,

47 ppf

Same

These circuit references

not assigned

Lis%

if

I&k&a&Fers Code

quantity used

*lo%,

as

C43

in

the instrument.

500 vdcw

500

vdcw

Letters

For

Replaceable

V*

QQ*

V*

Pa

14-28

13-33

14-67

:s

Tableii.

2

1

Sect. V Page 6

Model 122A

TABLE OF REPLACEABLE PARTS

CIRCUrr

REF.

c221

c222

C223

C224

C225

C226

C227

C228

C229

DESCRIPTION, MFR.

Capacitor: fixed, mylar,

0.2 pf *5%, 200 vdcw

Capacitor: fixed, mylar,

pf

.02

Capacitor: variable, mica,

170

Capacitor: fixed, mylar,

.0018 pf *5%, 200 vdcw

Same as C213

Capacitor: variable, ceramic,

7

Capacitor: fixed, paper,

.22 pf

Capacitor: fixed, paper,

.022 pf

Capacitor: fixed, paper,

2200

*5%, 200 vdcw

-

790

-

45

wf

+lo%,

*lo%,

wf

*lo%,

ppf,

175 VdCW

,500 VdCW

400 vdcw

600

*

WICW

600 vdcw

&

MFR.

DESIGNATION

cw*

QQ*

cw*

L*

cc* cc* cc*

@

STOCl

NO.

16-121

16-120

13-32

16-119

13-1

16-48

16-12

16-22

1

C230

C231

C232

C233

C234

C235

C236

C237

*

See List

#

Total quantity useddn the instrument.

Capacitor: fixed, mica,

220 ppf

Capacitor: fixed, mica,

150

Capacitor: fixed, mica,

1500

game as C44

Zapacitor: fixed, mica,

470

Same

Zapacitor: fixed, silver mica,

30 ppf +5%, 500 vdcw

2apacitor: fixed, sflver mica,

150

bf

MKdactuErs Code Letter8 For Replaceable

*lo%,

wf

*lWo,

wf

*2Wo,

wf

as

C44

wf

*5%, 500 vdcw

500 vdcw

500

500 vdcw

VdCW

14-66

1

V*

14-150

1

V*

,

14-1500

Z*

14-62

1

V*

Z*

A*

Parts

15-146

15-31

Table".

1

.._..

MI

del

:IRcui

REF.

C:

238

C:

299

C:

300

C:

301

C:

302

C:

303

C:

304

122A

DESCRIPTION, MFR.

thri

These circuit references

not assigned

Same

as

ClOl

Same

as

C9

Capacitor: fixed, mica,

390 ppf

This circuit reference

not assigned

Same

as

C5

TABLE OF REPLACEABLE PARTS

*

&

MFR. DESIGNATION

*5%,

500 vdcw

Z4

@

14-43

STOC NO.

-

V

Page

Sect.

#

1

7

C:

10

5

C:

IO6

c3

107

c3

I08

c3

109

c3

10

c3

11

c3

12

c3

13

C314 thru C320

Capacitor: fixed, tubular,

.Ol

pf

*2%, 400 vdcw

Capacitor: fixed, paper,

3300 pf *2%, 6000 vdcw

Eapacitor: fixed, paper,

ppf

C28

C306

C307

pi

C9

*209b,

+la,

*lwo,

1500

game

as

same

3ame

as

2apacitor: fixed, paper,

.051 pf

zapacitor: fixed, paper,

.015

lame

as

'hese circuit references

not assigned

5000

200 vdcw

3000 vdcw

vdcw

cc*

Z*

cc

*

6

-

109

6

-94

6-125

6-84

5-126

1

2

1

3f

#

Total quantity used in the instrument.

Manufacturers Code Letter8 For Replaceable

Pa

'

Tableii.

Sect. V Page 8

Model 122A

CIRCUlT

REF.

C321

C322A

C

323

C324

C325

A,

B

C326

C327

C328

TABLE

DESCRIPTION,

Capacitor: fixed, electrolytic,

120 pf, 350 vdcw

Same

as

C23A

Same

as

C28

Capacitor: fixed, electrolytic,

40

pf

,

450 vdcw

Capacitor: fixed, electrolytic, 2 sections,

20 pf/sect., 450 vdcw

This circuit reference

not assigned

Same

as

C28

rhis circuit reference

not assigned

MFR.

*

OF

REPLACEABLE PARTS

&

MFR.

DESIGNATION

cc

*

@

STOCl

NO.

18-62HP

18-40HP

18-22HP

-

#

1

C329

C330

2331

2332

2333

2334

2335

2R301 2R302

2R307

2apacitor: fixed, paper,

0.1 pf

Same

rhis circuit reference

not

2apacitor: fixed, electrolytic,

1000

Same asC28

Same

!ame

?ectifier,

thri

?ectifier, silicon: SD500 Audio Devices

*lo%,

as

C28

assigned

wf,

as

C9

as

C28

silicon:

400 VdCW

50 vdcw

lOOV,

,

.

'.

P.LV.

cc*

AA*

16-35

.8

-

77HP

812-134

12-147

1

5

See

#

Total

1'

List of Manufacturers Code Letters

quantity used

in

the instrument.

For

Replaceable

Pa

s

Table".

-

Model 122A Sect. V Page

9

CIRCUFI:

REF.

DS301

DS302 thri DS305

F301

J1

52

TABLE

~ ~~ ~~

DESCRIPTION, MFR.

Lamp, incandescent: 6

2 pin base, GE#12

Lamp, incandescent: 6

.15 amp,

Fuse, cartridge: 2 amp, slow-blowfl

1 a (230 v only)

or

Consists

Connector Assembly:

binding post and ground link Binding post insulator: double, black Binding post: insulated, black Binding post: insulated, red

Consists

Connector Assembly:

binding post and ground link

#47

of

of:

OF

REPLACEABLE PARTS

*

&

MFR. DESIGNATION

-

8V,

-

8V,

N*

E*

HP HP* HP HP

HP*

211-78

211-47

211-16

G-76K

*

AC-54A AC-1OC

*

AC-1OD

*

G-76J

@

STOCE NO.

#

1

4

1

1 4 3 5

1

53 thru

JlOO

JlOl

L201 L202 thru

L300 L301 P301

Binding post insulator: double, black Binding post: insulated, black Binding post: insulated,

t'hese circuit references

not assigned

Zonsists

Binding post insulator: single, black Binding post: insulated, black Binding post: insulated, red

:oil,

rhese circuit references

not assigned :oil, Power Cord Elec. Cords Co

R.F.:

RF.:

of:

500 ph

200

ph

red

HP HP HP

HP HP* HP

CG

*

* *

*

* *

*

AC

-

54A AC-1OC AC-1OD

AC -54D AC-1OC AC-1OD

18-37

18-34 312-56

1

1 1

I:

See

Y

Total

tf

II

Lis1

quantity used in the instrument.

Manufacturers Code

Letters

For

Redaceable

Pn

:s

Table"

-

.

Sect. V Page 10

CIRCUIT

REF.

Q301

DESCRIPTION, MFR.

Transistor: germanium CTP-1113

TABLE OF REPLACEABLE PARTS

@

STOCK

*

&

MFR. DESIGNATION

Clevite

NO.

213-2

-

Model 122A

#

1

Q302

R1

R2

R3

R4

R5

R6

R7

R8

R9

Transistor: germanium TS-6OOC

Resistor: fixed, deposited carbon,

1

megohm

*l%,

1/2

W

Resistor: fixed, composition,

1

megohm *5%, 1/2

W

Resistor: fixed, deposited carbon,

900,000

ohms

*l%,

1/2

W

Resistor: fixed, deposited carbon,

111,000 ohms

*l%,

1/2

W

Resistor: fixed, deposited carbon,

990,000 ohms

*l%,

1/2

W

Resistor: fixed, deposited carbon,

9100 ohms

*l%,

1/2

W

Resistor: fixed, deposited carbon,

1000 ohms

*l%,

1/2

W

Resistor: fixed, composition,

100,000 ohms

Same

as

R1

f100/0,

1/2

W

CB*

NN*

B*

NN*

B*

113-1

-

1M

33

23-1M-5

33-900K

33-111K

33-990K

33-9.1K

33-1K

23-100K

1

2

3

2

4

R

10

R11

R12

R

13

R

14

R15

R

16

See

#

Total quantity used

Same

11

List of Manufacturers Code Letters For Replaceable

as

R2

as

R3

as

R4

as

R5

as

R6

as

R7

as

R8

in

the instrument.

Parts

Table".

del

122A

TABLE OF REPLACEABLE PARTS

Sect.

V

Page

11

mcum

REF.

.7,18

.9

!O,

21

!2

13

!4

!5

16

DESCRIPTION,

Resistor: fixed, composition,

100

ohms

Resistor: fixed, composition,

470

ohms

Resistor: fixed, deposited carbon,

59,480

Resistor: fixed, deposited carbon,

80,000

Resistor: variable, composition,

linear taper,

Resistor: variable, Composition,

250,000

Resistor: fixed, composition,

1000

Resistor: fixed, composition,

18,000

ohms

MFR.

*lo%,

+lo%,

1/2

*l%,

500

*2W0, .25

*lo%,

*lo'%,

W

1/2

1

W

ohms

1/2

*

&

MFR. DESIGNATION

W

*lo%

W

B*

NN*

I*

BO*

B*

@

STOCl

NO.

23-100

23-470

33-59.48E

31-80K

210-25

210-239

23-1K

23-18K

#

-

15

3

4

2

6

4

17

18,29

'0

1

A,

B

2,

33

4,35

6, 37

8

Resistor: variable, composition,

250,000

Same as

Resistor: fixed, deposited carbon,

8700

Resistor: variable, wirewound,

dual concentric,

*lo%,

Resistor: fixed, deposited carbon,

98,000

Resistor: fixed, composition,

16,.000

Same as R17

Resistor: fixed, composition,

22,000

ohms

R17

ohms

2

w

ohms

*20%, 1/4

il%,

1

500

*l%, 1 W

*5%,

W

ohms each

1/2

W

2

W

BO*

NN*

BO*

NN*

B*

210-228

31-8.7K

210-129

31

-98K

13-16K-5

15 - 22K - 5

2

1

4

2

?e

!'Lis1

otal quantity used in

If

Manufacturers Code Letters For Realaceable

the

instrument.

Pa

s

Table!'.

-

Sect. V Page

CIRCUlT

REF.

12

DESCRIPTION,

TABLE OF REPLACEABLE PARTS

($3

STOCl

MFR.

*

8z

MFR. DESIGNATION

NO.

Model

#

122A

R39

R40,41

R42

R43

R44

R45

R46

R47

R48,4

R50,51

Resistor: fixed, composition,

8200

ohms

Same

as

*lo%, 1

R20

R22

R23

R24

R25

R26

R27

R17

R32

W

24-8.2K

2

R

52

R53

Same

rhis circuit reference

not assigned

R54,55

R56,57

R

58

3

59

360

See Lis1

#

Total quantity used

Same

?esistor: fixed, composition,

18,000

E

Manufacturers Code Letters

as

R30

as

R34

as

R17

as

R39

as

R38

ohms

in

the instrument.

*lo%, 2

W

.

'.

For

Replaceable

B*

Pa

t5-18K

s

Table'?.

1

3

-

lode1

122A

CIRCUIT

REF.

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

*

&

MFR. DESIGNATION

$2

STOCE

NO.

-

Sect.

V

Page

13

#

361

362,63

?64,65

?66,67

?68

?69

3

70

371

372

thru

?

100

3101

Resistor: fixed, composition,

47,000

Resistor: fixed, composition,

24,000

Resistor: fixed, deposited carbon,

1.15

Resistor: fixed, deposited carbon,

2

Resistor: fixed, composition,

270,000

Resistor: fixed, composition,

560,000

Resistor: fixed, composition,

1.5

Resistor: fixed, composition,

56,000

These circuit references

not assigned

Resistor: variable, composition,

linear taper,

ohms

megohms

ohms

megohms

ohms

*lo%, 2

*5%,

1

+l%,

*l%, 1/2

*lo%,

+lo%,

*lo%, 1/2

*lo'%, 1/2

500,000

W

1/2

W

1/2

ohms

W

B*

NN*

B*

G*

25-47K

24 -24K-

5

33-1.15M

33

-2M

23-270K

-

560K

23

23-1.5M

23

-

56K

210-20

1

4

2

3

2

1

3

1

2

?

102

?

103

3

104

1105

?

106

3107

See Lis1 Total quantity used in the instrument.

Resistor: fixed, composition,

120,000

Resistor: fixed, composition,

1

megohm

Same

Same as

Resistor: fixed, composition,

22,000

Resistor: variable, linear taper,

50,000

If

Manufacturers Code Letters

as

ohms

R8

R17

ohms

*lo%,

*lo%, 1/2

*20%,

1/3

1/2

W

For

Replaceable

B*

BO*

Pa

23-120K

23-1M

23-22K

210-245

s

Table".

1

9

3

4

Sect. V Page 14

CIRCUIT

REF.

DESCRIPTION, MFR.

TABLE OF REPLACEABLE PARTS

@

STOCK

*

€i

MFR. DESIGNATION

NO.

Model 122A

#

R

108

R109

RllO

Rlll

R112

R113

R114

R115

R116

Resistor: variable, linear taper,

1/2

W

1/2

1

W

5000 ohms *200/0, 1/2

Resistor: fixed, compos ition,

2700 ohms

Resistor: variable, linear taper,

2500 ohms, tol. 200/0, 1/2

Resistor: fixed, composition,

12,000 ohms

Resistor: fixed, composition,

100,000 ohms

Resistor: variable, composition, 2 sections,

50,000 ohms +200/0; rear section: 100,000 ohms (part of S103)

Same

as

Same

as

Same

as

RllO

R112

Rlll

*100/0,

*lo%,

t

20%

BO*

B*

BO*

B*

BO*

210-246

23-2.7K

210-243

23-12K

24-100K

210-226

1

2

3

2

R117,118

R119

R120

R121

R122

R123

R124

*

See

It

#

Total quantity used

Same

Resistor: fixed, composition,

Resistor: fixed, composition;

Resistor: fixed, composition,

Same

Lis1

,f

Manufacturers Code Letters

as

R17

30,000 ohms *5%, 2

6800 ohms

1800 ohms

as

*lo%,

R120

R119

in

the instrument.

1/2

2

1/2

W

For

Replaceable

B*

Pa

2

5-30K - 5

23-6800

25-6800

23-1800

8

Table".

2

1

Modi

r

CII

R

-

el

122A

3cum

:EF.

DESCRIPTION,

TABLE

MFR.

OF

REPLACEABLE PARTS

*

&

MFR. DESIGNATION

@

STOCH

NO.

-

Sect.

V

Page 15

#

R12

R

I<

R2(

R 2C

R2C

R 2C

R2G

!5

19

10

)1

12

)3

14

)5

)6

I7

I8

These circuit references

thru

not assigned

Same as R25

Same

as

R103

Same

as

R17

Same

as

R103

This circuit reference

not assigned

Resistor: fixed, deposited carbon,

83,000

This circuit reference

not assigned

Res istor: fixed, composition,

10,000 ohms

Same

as

ohms

R62

*l%,

&lo%,

1/2

W

NN*

B*

33-83K

23-10K

1

-

*

#

R2G

R21

Set

To

19

0

1

2

3

4

3

I'LiSl

tal

quantity

Same

as

R8

Resistor: variable, linear taper,

200,000 ohms, tol. 20%) .25 (not separately replaceable) (part of S202)

Resistor: fixed, composition,

120,000 ohms *5%, 1/2

Resistor: fixed, deposited carbon,

71,560 ohms

Same as R211

Resistor: fixed, composition,

68,000 ohms

fManufsuyersCode Letters

used

in

*l%,

*lo%,

the

instrument.

1/2

W

For

Replaceable

BO*

B*

NN*

B*

Parts

210-241

23-120K-5

33-71.56K

23-68K

Tableft.

1

2

1

Sect. V Page 16

CIRCUIT

REF.

R215

This circuit reference

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

not assigned

*

&E

MFR. DESIGNATION

@

STOCE NO.

-

Model 122A

#

R216

R217

R218

R219,220

R221

R222

R223

R224

R225

R226

Same

as

R26

Same

as

R17

This circuit reference

not assigned

These circuit references

not assigned

Same

as

R112

Resistor: fixed, composition,

47,000 ohms

Same

as

R25

Resistor: fixed, composition,

27,000 ohms

Resistor: fixed, composition,

680,000

Same

as

R60

ohms

+IO%,

+lo%,

112

W

B*

23-47K

13-27K

13-680K

5

6

2

R227

R228

R229

R230

R231

R232

:

See Lis

#

Total

Same

as

R224

:

Resistor

10,000 ohms, tol. 30%, 113

Same

Resistor: fixed, composition,

430,000

Resistor: variable, linear taper,

250,000

Resistor: fixed, composition,

330,000 Electrical value adjusted

bf

Manufacturers Code Letters For Replaceable

quantity

used

variable, 1inea;"tape

as

R224

ohms

*5%, 112

ohms,

ohms

in

the

tol. 20%, 114

*lo%,

instrument.

112

W

r,

W

at

factory

Eo*

B*

BO*

B*

Pa

l10-240

13

/

430K-

!lo-244

t3-330K

8

Table".

5

1

-

ode1 122A

CIRCUIT

REF.

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

*

i3x

MFR. DESIGNATION

@

STOCK NO.

Sect.

V

Page 17

#

3233

R234

R235

R236

R237

R238

R239

R240

R241

Resistor: fixed, composition,

220,000 ohms Electrical value adjusted

Resistor: fixed, glass body,

27,000 ohms

Resistor: fixed, composition,

24,000 ohms +5%, 1/2

Resistor: fixed, composition,

160,000 ohms +5%, 1/2

Same

as

R2

Resistor: fixed, composition,

2 megohms

Same

as

Rl9

Same

as

R224

Resistor: fixed, composition,

100,000 ohms

+lo%,

+5%,

+lo%,

4

1/2

W

2

W

at

factory

B*

AB*

B*

13-220K

134-27K

I3

-

24K-

5

13-16OK-5

13-2M-5

!5-100K

1

R242

R243

R244 thru Et246

3247

3248

3249

3250

3251

See List

#

Total quantity used in

Resistor: fixed, composition,

820,000 ohms

Same

as

These circuit references

not assigned

Resistor: variable, linear taper,

1000 ohms, to1 20%, 1/2

Same

as

Resistor: fixed, composition,

270,000 ohms +5%, 1/2

Resistor: fixed, composition,

3900

Same

as

3f

Manufacturers Code

R19

R62

ohms

+lo%,

R107

the

&lo%,

1/2

W

Letters

instrument.

W

For Replaceable

B*

BO*

B*

PS

!3-820K

10-247

3-270K-5

3-3.9K

s

Table".

2

1

Sect. V Page

18

Model 122A

TABLE OF REPLACEABLE PARTS

CIRCUlT

REF.

R252

R253

R254

*,B

R255,256

R257

R258

R259

R260

DESCRIPTION, MFR.

Same

as

R106

Resistor: fixed, composition,

47,000 ohms

Resistor: fixed, deposited carbon,

3 megohms

Resistor: fixed, deposited carbon,

3 megohms

Same

as

R113

Resistor: fixed, composition,

39,000 ohms

Same

as

R68

Resistor: fixed, deposited carbon,

20,000 ohms

*lo%,

*I%,

*l%,

*lo%,

*l%,

1

1/2

*

&s

MFR. DESIGNATION

1

W

1/2

W

B"

NN"

B"

NN'

@

STOCP NO.

24-47K

31-3M

33-3M

23-39K

33 -20K

-

#

1

2

1

R261

R262

R263

R264 thru R299

R300

R301

R302

R303

Same

as

R66

Resistor: fixed, deposited carbon,

200,000 ohms

Resistor: fixed, deposited carbon,

1.8

megohms + 1%,

These circuit references

not assigned

Resistor: fixed, composition,

1000 ohms

Same

as

R25

Same

as

R222

Resistor: fixed, composition,

150,000 ohms

*l%,

*lo%,

1

1/2

W

,

.

'-

2

W

NN*

B*

33-200K

33-1.8M

24-1K

2 5- 150K

I

1

See Lis1

#

Total quantity used

if

Manufacturers Code Letters

in

the instrument.

For

Replaceable

Pa

8

Table".

-

cc-

122A

-

WIT

F.

,311

TABLE OF REPLACEABLE PARTS

DESCRIPTION, MFR.

Resistor: fixed, composition,

560,000 ohms

Same

as

R103

Same as R70

Resistor: fixed, composition,

3 megohms *5%, 1/2

Resistor variable, linear taper,

1

megohm, tol. 30%, .25

Resistor: fixed, composition,

4.7 megohms

Resistor: fixed, composition,

5.6 megohms

*lo%,

+lo%,

*lo%,

*

t3z

MFR. DESIGNATION

1

W

2

W

2

W

B*

BO*

B*

~

@

STOCK NO.

l4 - 560K

13-3M-5

210-242

25-4.7M

25-5.6M

-

Sect. V Page 19

#

2

1

3

1

2

,315

'thru

Resistor: variable, composition, linear taper,

3.5 megohms

Same

as

R225

Same

as

R224

Same as R107

Resistor: fixed, composition,

56,000 ohms

Resistor: fixed, composition,

2.2 megohms

Resistor: fixed, composition,

8.2 megohms

Same

as

RlOl

Resistor: variable, composition,

200,000 ohms *200/0, 1/4

(not separately replaceable)

k.3096,

*lo%,

1/2

1

1/2

2

W

(part

of

S301)

I*

B*

BO*

2

10- 150

14-56K

!3-2.2M

!5-8.2M

!lo-224

1

3

1

-

Lid

al

quantity

Same as R222

If

Manufacturers Code Letters

used

in

the

instrument.

For

Replaceable

Pa

s

Table".

Sect. V Page 20

CIRCUIT

REF.

DESCRIPTION, MFR.

TABLE OF REPLACEABLE PARTS

@

STOCE

*

&

MFR. DESIGNATION

NO.

-

Model 122A

c

#

R325

R326

R327

R328

R329,330

R331,332

R333

R334

R335

R336

Same as R70

This circuit reference

not assigned

Same as R25

Same as R222

These circuit references

not assigned

Same as R103

Same as R304

Resistor: fixed, composition,

470,000 ohms *100/0,

Same

as

R222

Same as R103

1

W

B*

24-470K

1

R337

R338

R339

R340

R341

R342

See "List

1

Total quantity used in the instrument.

Resistor: fixed, wirewound,

3500 ohms

Resistor: fixed, deposited cdrbon,

405,000 ohms Electrical value adjusted at factory

Resistor: fixed, deposited carbon,

136,700 ohms

Electrical value adjusted at factory

Resistor: fixed, deposited carbon,

200,000 ohms

Resistor: fixed, composition,

22 megohms

Resistor: fixed, composition,

10,000 ohms

of

Manufacturers Code Letters

*lo%,

10

*l%,

*lo%,

W

1/2.w

1/2

2

W

I

W

For

Replaceable

R*

NN*

B*

Pa

Z6

-

102

33 -40 5K

33-136.7K

33-200K

i3-22M

!5-10K

s

Table".

1

-

L_

V

del 122A

Ma

Sect.

TABLE OF REPLACEABLE PARTS

Page 21

-

@

'IRCUIT

C

REF.

-

R:

343

DESCRIPTION, MFR.

Resistor: fixed, deposited carbon,

1.88

megohms

*l%,

*

&

MFR. DESIGNATION

1/2

W

NN*

STOCK

NO.

33-1.88M

-

#

1

R:

344

345

346

347

348

349

350

351

352

353

Same as R308

Resistor: fixed, deposited carbon,

2.52 megohms

Same as R242

Resistor: fixed, composition,

82,000 ohms

Same

as

R60

Resistor: fixed, composition,

150 ohms

Same

as

R26

Resistor:

15,000 ohms

Same

Resistor: fixed, composition,

2.7 ohms

as

fixed,

R103

*l%,

*lo%,

2

composition,

*lo%,

1/2

W

1/2

W

1/2

W

1

W

NN*

B*

33-2.52M

23 -82K

25-150

23-15K

24-2.7

2

1

R:

354

355

R:

356

R:

357

R:

358

R:

359

-

See

11

*z

rotal

#:

Resistor: fixed, deposited carbon,

4440 ohms

Resistor: fixed, deposited carbon,

27,500 ohms

Same

as

Same as R345

Resistor fixed, composition,

2.4 megohms

Resistor: fixed, deposited carbon,

500 ohms

List

of

Manufacturers Code Letters For Replaceable

quantity used

*l%,

R308

*5%,

*l%,

1/2

in

the instrument.

1/2

1

1/2

W

NN*

B*

NN*

Parts

33-4.44K

31-27.5K

23-2.4M-E

33-500

Table".

1

-

Sect. V Page 22

CIRCUIT

REF.

DESCRIPTION, MFR.

TABLE

OF

REPLACEABLE PARTS

*

&

MFR. DESIGNATION

@

STOCE

NO.

Model 122A

-

#

R360

R361

R362

R363

s1,2

53

54 thru

5100

5101 3102 5103

Resistor: variable,

500 ohms *30%0, 3/10

Resistor: variable, wirewound,

25 ohms

Same as R103

Resistor: fixed, composition,

470,000 ohms

Vertical Attenuator Switch

Assembly: complete

Presentation-Polarity Switch

Assembly: complete

These circuit references

not assigned Switch, toggle: SPST Switch, toggle: SPDT

Part

of 5204

*lo%,

linear

2 W (includes S301)

*lo%,

less components

W

1/2

taper,

W

BO*

B*

HP

*

W*

HP*

W*

D* D*

210-115

210-188

23-470K

122A-19D

310-251

122A-19B 310-250

310-11 310-12

1

2

1

1 1

3104 thru 3200

5201 3202

3203

3204

3205 thru 3300

3301

3302

See

It

Total quantity used

These circuit references

not assigned Sync-Trigger Level Switch Assembly Switch, trigger-level

(part of R210 and S201)

This circuit reference

not assigned

Sweep Time-Horizontal Sensitivity

Switch Assembly: includes S103

These circuit references

not assigned

Part of R361

This circuit reference

not assigned

Lid

If

Manufacturers Code Letters

in

the instrument.

For

Replaceable

HP*

Pa

122A-19C

122A- 19A

Ls

Table".

1

le1 122A

bloc

Sect. V Page 23

-

C!

S3(

T31

v1

v3

v4 V6 V8

v9

v1

Kcurr

REF.

13 01 02

92

25 97

0,ll

TABLE

DESCRIPTION, MFR.

Switch, rotary

l'

ransformer, power

l'ransformer,

rube, electron: 12AU7 rube, electron: 6DJ8/ECC88 Same as V1 Same as V3 Same as V1

rube, electron: 6AU6 Lamp, glow, 1/25

HV

W

*

OF

&

REPLACEABLE PARTS

MFR. DESIGNATION

W*

310-177

HP

*

120A

HP

*

-11A-1

2

N*

12 - 12 AU7

212-6DJ8

212 -6AU6 211-43

zz* zz*

zz*

1

2 thru

v1

00

v1

01

v1

02 03 thru

v1

v2

00

v2

01

02

v2

03,204

v2

05

v2

06 thru

v2

09

v2

10

These circuit references

not assigned

Same

as

V3

Tube, electron: 12AT7 These circuit references

not assigned Tube, electron: 6AN8 l'ube, electron: 6U8 Same as V1

Same as V202

These circuit references

not

assigned

Neon, lamp, aged and selected,

blue code

zz*

zz* zz*

HP*

2 12

-

12AT

212-6AN8 212-6U8

G-84B

7

-

lee ~~Lisl

*S

'otal quantity used

#1

of

Manufacturers Code Letters For Replaceable

in

the instrument.

Parts

Table".

Sect. V Page 24

Model 122A

CIRCUIT

REF.

V211 thru V213

V214

V215 thru V217

V219 thru

V300 V301

V302

V303,304

V305

TABLE

DESCRIPTION, MFR.

as

Same

Neon, lamp, aged and selected,

Same

These circuit references

Same Tube, electron: 6AQ5 Tube, electron: 5642 Tube, cathode ray: 5AQP

V10

green code

as

V210

not assigned

as

V1

flat-faced, 5"

OF

*

&

MFR. DESIGNATION

REPLACEABLE PARTS

(8

STOCE NO.

G

-84D

HP

*

zz*

ZZ*

1

2 - 6AQ 5

2 212

-

5642

212 -5AQF

1,2,7,

11

-

#

1

2 1

V306

V307 V308 V309

V310

V311 thru

V314 v315

V316,317

V318 thru

V321,322

Tube, electron: 12B4A Same

as

V202

Same

as

V306

Same

as

V9

Tube, electron: 5651 These circuit references

not assigned

Same as V10

Same

as

V215

These circuit references

not assigned

Same as V10

.

212-1284,

ZZ*

21 2

-

ZZ*

..

56 51

2

1

)f

*

See Lis1

#

Total quantity used

Manufacturers Code Letters For Replaceable

in

the instrument.

Pa

.s

Tablet'.

del

122A

IRcurl REF.

DESCRIPTION,

MISCELLANEOUS

TABLE OF REPLACEABLE PARTS

MFR.

*

&

MFR. DESIGNATION

___~

~

@

STOC:

NO.

-

#

Sect. V

Page

\

25

Fuseholder Jewel

Pilot

Light Assembly

Knob HORIZ.

SCALE LIGHT, INTENSITY

(rack

FOCUS, INTENSITY, SCALE

LIGHT (cabinet model only)

Knob CHAN. APOLARITY Knob HORIZ. POS. (Cabinet model only) Knob A+B VERT. SENS., SWEEP

TIME-HORIZ. SENS., VERT. PRESENTATION, SYNC

hob TRIGGER LEVEL, A+B VERT.

SENS., SWEEP TIME-HORIZ SENS. hob B VERT. POS. hob: A VERT.

POS.,

FOCUS,

model only)

POS.

T*

AD*

HP*

HP* HP* HP*

HP*

HP* HP*

HP

*

140-16

145-23A 145-25 G-74D

G

-74E G-74G G-74Q

3-74AU

3-74AW 3-74BE

1 1

1

4

3

1 1

5

4

1

)tal

quantity used

f

Manufacturers Code

in

the instrument.

Letters

For

ReDlaceable

Pa

E

Table''.

LIST

OF

CODE LETTERS USED

TO

DESIGNATE THE MANUFACTURERS

IN

TABLE

OF

REPLACEABLE PARTS

CODE

LCR

A

B

C

D E F

G

H

HP

I

J

K

L

M

N

0

P

Q

R

S

T

U

V W X

Y

Z

AA

BB

cc

DD

EE

FF

GG

HH

II

JJ

KK LL

MM

NN

00

PP

QQ

RR

ss

TT

uu

vv ww

xx

YY

22

AB AC

AD AE AF

AG

AH AI AJ

MAN U FACTU

RER

Aerovox Corp. Allen-Bradley Amperite Arrow,

Bussman

Carborundum

Centrala

Co.

Hart

&

Hegemon

Manufacturing Co.

Co.

b Cinch-Jones Mfg. Co. Hewlett-Packard Clarostat Mfg.

Cornell

Dubilier

Hi-Q

Division

Erie

Resistor Corp.

Fed. Telephone

General General

Co.

Elec.

Co.

of

Aerovox

81

Radio Corp.

Electric

Co.

Electric Supply Corp.

Girard-Hopkins

Industrial

International

Lectrohm Littlefuse

Products

Resistance

Inc. Inc.

Co.

Maguire Industries Inc.

Micomold

Oak

P.

Radio Corp.

Sangamo

Radio

Corp.

Manufacturing Co.

R.

Mallory

Co.,

of

America

Electric

Inc.

Co. Sarkes Tanian Signal Indicator Sprague Stackpole Carbon

Sylvania

Western

Wilkor

Products,

Electric

Co.

Products Co.

Co.

Inc.

Amphenol

Diol Light Leecraft Manufacturing

Switchcraft,

Co.

of America

Inc.

Co.

Gremar Manufacturing Co. Carad

Corp.

Electra

Manufacturing Co. Acro Manufacturing Co. Alliance Manufacturing Co. Arco

Electronics,

Inc.

Astron Corp. Axel Brothers

Belden

Inc.

Manufacturing

Co. Bird Electronics Corp. Barber

Colman

Co.

Bud Radio Allen D. Cordwell Mfg.

Cinema

Inc.

Engineering

Co.

Any brand tube meeting

RETMA standards.

Corning

Dole Products,

Gloss

Works

Inc.

The Drake Mfg. Co.

Elco

Corp.

Hugh

H.

Thomas A. Edison,

Fansteel Metallurgical

General

The Gudeman

Eby Co.

Ceramics

Co.

Inc.

Corp.

&

Steatite Corp.

ADDRESS

New

Bedford, Mass.

Milwaukee 4,

New

Hartford,

St.

Louis,

Niagara Falls, Milwaukee Chicago 24,

Palo

Alto, Dover, South Plainfield,

Olean,

Erie

6,

Clifton,

Schenectady

Son

Francisco,

Oakland,

York,

N.

Pa.

N.

Conn.

Mo.

I,

111.

Calif.

H.

Y.

J.

5,

Calif.

Wis.

Y.

N.

Wis.

N.

Calif.

Danbury, Conn. Philadelphia

Chicago 20,

Des Plaines,

8,

Pa.

111.

Greenwich, Conn. Brooklyn 37, Chicago 10, Indianapolis,

Harrison,

Marion, Bloomington,

Brooklyn

111.

37,

N.

111.

Ind.

J.

Ind.

N.

Y.

North Adams, Mass.

St.

Marys,

Warren,

New

Po.

York 5,

Pa.

N.

Y. Cleveland, Ohio Chicago

Brooklyn

New

Chicag:

York,

50,

111.

37, N.'Y.

N.

Y.

22,

111.

Wakefield, Mass.

Redwood City, Kansas Columbus

City,

16,

Calif.

Mo.

Ohio

Alliance, Ohio

New

York

13,

N.

Y.

East

Newark,

Long Island City, Chicago

44,

111.

N.

J.

N.

Cleveland 14, Ohio Rockford, Cleveland

Plolnville,

Burbank,

Corning,

111.

3,

Conn.

Calif.

N.

Y.

Ohio

Columbus, Neb. Chicago 22,

Philadelphia 24, Philadelphia 44,

West

North Chicago,

Keasbey,

Sunnyvale,

111.

Orange,

N.

J.

Calif.

Pa.

N.

111.

J.

CODE

LElTER

Y.

J.

Y.

BZ CA CB CD

CE

Y.

CF CG

CH CI CJ

CK CL CM

CN

co

CP

CQ CR

cs

CT

cu

cv

cw

MANU FACTU

AK

Hammerlund Mfg.

AL

Industrial Condenser Corp.

AM

Insuline

AN

A0 AP AQ

AR AS AT AU AV

AW AX AY A2

BA

BC BD

BE

BF

BG

BH

BI

BJ BK BL BM BN

BO BP

BQ

BR

BS

BT BU BV BW BX BY

Corp.

Jennings

E.

Radio Mfg.

F. Johnson Co. Lenr Electric Mfg. Micro-Switch Mechanical Industries Prod. Co.

Model Eng. & Mfg., The Muter

Co.

Ohmite Mfg. Co.

Resistance Products Radio Condenser

Shallcross Manufacturing Solar Manufacturing Sealectro Corp. Spencer Thermostat

Stevens

Manufacturing Torrington Manufacturing Vector

Electronic

Weston

Electrical

Advance E.

1.

DuPont

Electric

Electronics Tube Corp.

Aircraft Radio Corp. Allied Control Augat Brothers, Inc.

Carter

Radio

CBS Hytron

Radio

Chicago Telephone Supply

Henry L.

Crowley

Curtiss-Wright Corp. Allen

B.

DuMont Labs

Excel

Transformer

General

Radio Co.

Hughes Aircraft

International

James Knights Mueller

Electric

Precision

Thermometer Radio Essentials Roytheon Manufacturing

Tung-Sol Lomp Works,

Varian Associates

Victory

Engineering Corp.

Weckesser

Co.

Wilco Corporation

Winchester

Electronics,

Malco Tool & Die Oxford Electric Corp.

Comloc-Fastener Corp. George

K.

Garrett

Union Switch & Signal Radio Receptor

Automatic

Bassick

Birnbach

Co.

Radio

&

Precision

Fischer Specialties Telefunken

(c/o

Potter-Brumfield Cannon

Electric

Dynac,

Inc.

Good-All

Electric

RER

Co.,

of

America

Co.

Inst.

81

Relay

Co.,

Inc.

Division

&

Co.,

Co.

Rectifier

Co.

Inc.

Co.

MVM,

Co.

Mfg.

Inc.

Corp.

Inc.

Co.

Corp.

Electric

Inc.

Corp.

&

Inst.

Co.

Inc.

Mfg. Co.

Inc.)

Co.

ADDRfSS

New

York

I,

N.

Y.

Chicago

Manchester,

Son

Waseca,

Chicago 47, Freeport, Akron Huntington, Chicago

Skokie,

Harrisburg, Camden

Jose,

8,

18,

Calif.

Minn.

111.

Ohio

5,

111.

3,

111.

N.

111.

Ind.

111.

Pa.

N.

J.

H.

Collingdale, Pa.

Lor Angeles 58, New Rochelle,

Calif.

N.

Y.

Attleboro, Mass.

Mansfield, Ohio

Van

Nuys,

Calif.

Los Angeles

Newark

5,

65,

Calif.

N.

J.

Bxbank, Calif. San Francisco, Calif. Philadelphia 18,

Boonton,

New

York 2

N.

Pa.

J.

I,

N.

Y.

Attleboro, Mass.

Chicago,

111.

Danvers, Mass. Elkhart, Ind.

West

Orange,

Carlstadt,

Clifton,

N.

J.

N.

J.

N.

J.

Oakland, Calif.

Cambridge Culver

El

Segundo,

Sandwich,

City,

39.

Calif.

111.

Mass.

Calif.

Cleveland, Ohio

Philadelphia 30,

Mt. Vernon,

Newton, Newark

4,

Palo

Alto,

Union,

N.

Chicago 30,

Indianapolis,

Santa Monica,

N.

Mass.

N.

Calif.

J.

111.

Pa.

Y.

J.

Ind.

Calif. Los Angeles 42, Calif. Chicago

Pqramus,

15,

N.

111.

J.

Philadelphra 34, Po.

Swissvale, Pa.

New

York

I

I,

N.

Y.

Yonkers,

N.

Y.

Bridgeport 2, Conn.

New

York

13,

N.

Y.

Cincinnati

New

Princeton,

York,

6,

N.

Ind.

Ohio

Y.

Los Angeles, Calif.

Palo

Alto, Calif.

Ogallala,

Nebr.

CLAIM

The instrument should be tested as soon as it is received. If it fails to operate

properly, or is damaged in any way, a claim should be filed with the carrier. A full

report of the damage should be obtained by the claim agent, and this report should be forwarded to equipment and arrange for repair or replacement. Include model number and serial number when referring to this instrument for any reason.

us.

FOR

We will then advise you of the disposition to be made of the

DAMAGE

IN

SHIPMENT

WARRANTY

Hewlett-Packard Company warrants each instrument manufactured by them to

be free from defects in material and workmanship. Our liability under this warranty

is limited to servicing or adjusting any instrument returned to the factory for that purpose and to replace any defective parts thereof. Klystron tubes as well as other

electron tubes, fuses and batteries are specifically excluded from any liability. This

warranty is effective for one year after delivery to the original purchaser when the instrument is returned, transportation charges prepaid by the original purchaser, and when upon our examination it is disclosed to our satisfaction to be defective. the fault has been caused by misuse or abnormal conditions of operation, repairs will he billed at cost. In this case, an estimate will be submitted before the work is

started.

If

any fault develops, the following steps should be taken:

1.

Notify

us,

giving full details and serial number. On receipt of this information, we will give you service data or shipping instructions.

2.

On receipt of shipping instructions, forward the instrument prepaid, to the

factory or to the authorized repair station indicated on the instructions. If requested,

an estimate of the charges will be made before the work begins provided the instrument is not covered by the warranty.

of

the difficulty, and include the model number

If

SHIPPING

All shipments of Hewlett-Packard instruments should be made via Truck or Railway Express. The instruments should be packed in a strong exterior container and surrounded by two or three inches of excelsior or similar shock-absorbing material.

DO

NOT

275

PAGE MILL ROAD

HESITATE TO

CABLE

CALL

PAL0 ALTO.CALlF.

"HEWPACK

ON

*

US

U.bA

r3eGbIv.n

IV

page

13,

LU

pdL.d&L-aAULl

Y-IL

,

pi

V~GUUI

G

J

~LAWA-

izontal Amplifier Adjustments), change to read: "Connect

B

'sawtooth generator' to channel

vertical input terminals."

9/16

122A

Section

IV

page

15,

in paragraph

4-12,

procedure 4 (Hor-

izontal kinplifier Adjustments), change to read: "Adjust

C235

on

SWEiW

TIME

switch for flat response."

(over)

-

122A

-

5/28

HEWLETT

-

PACKARD

CQ.

Model

1ZA

-

Serial

651

and

-

above:

/50/

+3@J

6

1

d

-i-

.-

0

4

3d

Model

122A

-,Page

3

Serial

CR202:

651

P3Ol:

R121t

R253:

R360: V204:

v215

thru

V2l7:

and above: (see partial schematic

Add diode, breakdown; -hp- Stock

Change to power cord; -hp- Stock

on

No. No.

page

G-29E-2, 812-106,

Change to resistor, fixed, composition,

-

+lo%, 2 W;

-hp- Stock

No.

25-lOK,

Mfr.,

B

Change to resistor, fixed,.composition,

-

+-lo%, % W;

-hp- Stock

No.

23-680K,

Mfr., Delete Change

'

Nlfr.,

0

f;o

tube, electron,

*

6C4;

-hp- Stock

Delete

2)

Mfr.,

10,000

68O,OOO

B

No.

ohms

212-6C4,

HP

Rp

10-14-

59

Model

122A

-

Page

3

Serial

CR202:

P3Ol:

R121:

R253:

R360:

V204:

v215

thru

V2l7:

T3Ol:

T302:

651

'

Change

NO,

Change Mfr,,

and

above:

Add

diode, breakdown;

Change

-

+lo%,

Change

-

+lo%,

Delete Change

Mfr.,

Delete

120A-llA-1,

to

2

to

bo

0

to

HP

(see partial schematic

power

-hp-

cord; -hp- Stock

Stock

on

No.

resistor, fixed, composition,

W;

-hp- Stock

Noo

25-lOK,

Mfr.,

resistor, fixed,.composition,

W;

-hp- Stock

tube,

.

electron,

No.

23-680K,

6C4;

-hp- Stock

Mfr.,

transformerg high voltage; -hp-

Mfro

transformer, power; -hp-

HP

Stock

page

G-29E-2, 812-106,

10,000

B 680,000

B

No.

Stock

Noo

2)

Wr., Mfr.,

ohms

212-6C4,

910-177p

HP

ohms

10-

14-

59

11/25

-

122A

HP 122AR, 122A Service manual

Specifications and Main Features

Frequently Asked Questions

User Manual