Tektronix DM505 Instruction Manual

Tektronix,

Inc.

p.0.

Box

500

Beaverton,

Oregon

97077

COMMlTED

EXCELLENCE

INSTRUCTION

MANUAL

Serial

Number

070-2692-

00

First

Printing

MAR

1979

WARRANTY

his

Tektronix product is

1

~d

against

defect

rials

and

orkmanship, under normal

use,

for

a

period

of

one

year

rrom

date

f

initial shipment.

Tektronix

will repair

or

replace, at its

option,

bose

products determined to

be

defective within the warranty

eriod and returned, freight prepaid,

to

a

Tektronix Service Center.

here

is

no

implied warra itness

of

purpoa

art

numl

ive

mate

nty

for

f

i

for

ierl

lease

direct all

I

vice

or

replacerr

earest Tektronix

aerrlce

lvertrer

or

Field

Office;

include

the

rypr

or

Jer

of

th

requests

..--..I--

be.

lent

par'

vright

@

tents

oft

.

.

ct

and

it s serial

number.

nix, Inc.

lay

not

b

-.

ts

to

the

-I

--

his publication

rr

e

reprad

vllJ

,,, ,,,

without the

permission

of

Tektronix,

Inc.

Prod

cove

lucts

of

red

by

Tektro

U.S.

an

nix,

Inc

d

foreis

.

and

its

subsidiaries

are

In

patents

and/or

pending

patents.
TEKTRONIX

E-MOBILE,

and

@

are

registered

traaemar~s

or

r

edronix,

1

Printed

in

U.S.A.

privileges are reservt

nc.

3nd

pril

TABLE

OF

CONTENTS

Page

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

LIST

OF

ILLUSTRATIONS

iv

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

LISTOFTABLES

V

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

OPERdTORS

SAFETY SUMMARY

~ii

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

SERVICING

SAFETY

SUMMARY ix

SECTION

1

SPECIFICATIOM

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

Introduction 1-1

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

Performance Conditions 1-1

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

Electrical Characteristics (Front Panel) 1-1

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

Dc

Voltmeter 1-1

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

Ac

Voltmeter

1-2

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

Ohmmeter

1-3

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

Dc

Ammeter 1-3

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

Ac

Ammeter

1-4

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

Electrical Characteristics

(Rear

Interface)

1-4

Dc

Voltmeter

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

1-4

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

Ac

Voltmeter 1-5

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

Ohmmeter

1-6

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

Miscellaneous 1-7

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

Environmental Characteristics

1-7

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

DM

505 Only 1-7

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

TM

500

Systems

1-8

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

Physical Characteristics 1-9

SECTION

2

OPERATING INSTRUCTIONS

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

l nstallation l nstructions 2-1

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

Controls

and

Connectors

2-2

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

Operators Familiarization

2-2

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

General Operating Information

2-2

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

l

nput

Connections

2-4

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

Si ne-wave Response

2-4

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

Dc

Voltage Measurements 2-4

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

Dc

Current Measurements

2-4

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

Ac

Voltage

and

Current Measurements

2-4

Resistance Measurements

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

2-4

Packaging Information

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

2-5

TABLE

OF

CONTENTS

(cont)

Page

SECTION

6

OPTIONS ..............................................

61

SECTION

7

REPLACEABLE ELECTRICAL

PARTS

SECTION

8

DIAGRAMS

AND

CIRCUIT

BOARD

ILLUSTRATIONS

Simplified

Block

Diagram

Rear

Interface

Connections

ND

Block

Diagram

Adjustment

Locations

Troubleshooling

Flow

Charts

Parts

Locations

Component

Reference

Charts

Schematics

SECTION

9

REPLACEABLE

MECHANICAL

PARTS

AND

EXPLODED

VIEW

CHANGE

INFORMATION

iii

Fig.

No.

Frontis

LIST

OF

ILLUSTRATIONS

Description

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

DM

505

Digital Multimeter

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

DM

505

Installation and Removal

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

Front

Panel

Controls and Connectors

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

Simplified Diagram

of

the

Ohms

Converter

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

Auto-zero timing intervars

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

Measurement

interval

timing

DM

505 Simplified Block

Diagram

8-2

A/D

Converter Block

Diagram

8-3

Adjustment Locations

TROUBLESHOOTING

FLOW

CHARTS

Power

Supplies

Dc

Volts

Dc

Current

Ohms

Ac

Volts

Ac

Current

Main

Board

(A10)

Display

Board

(A1

1)

Page

No.

LIST

OF

TABLES

Title

Page

No

.

ELECTRICAL CHARACTERISTICS (Front Panel)

1-1

DcVoltmeter

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

1-1

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

1-2

AC

Voltmeter

1-2

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

1-3

Ohmmeter

1-3

ELECTRICAL

CHARACTERlSTlCS

(Rear

Interface)

1-6

DcVoltmeter

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

1-4

1-7

AcVoltmeter

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

7-5

1-8 Ohmmeter

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

1-6

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

1-9 Miscellaneous 1-7

ENVIRONMENTAL CHARACTERISTICS

1-10

DM

505

Only

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

1-7'

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

1-1

1

TM500Systems

1-8

PHYSICAL CHARACTERISTICS

Physical

Characteristics

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

1-9

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

Current

Mode

input

Resistance

2-4

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

Ohmmeter Source Current

and

Voltage

2-5

Ohms

Converter Source Current

and

Maximum Full-scale Voltage

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

3-2

List

of

Equipment Requirements

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

4-1

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

Dc

Voltage

Accuracy

4-3

Ac

Voltage

Accuracy

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

...

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

4-4

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

Ohms Accuracy 4-6

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

Dc

Current Accuracy

4-6

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

Ac

Current Accuracy 4-7

Dc

Voltage Accuracy for

Rear

l

nterface

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

4-7

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

Ac

Voltage

Accuracy

for

Rear l nterface 4-8

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

Ohms Accuracy

for

Rear

Interface

4-8

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

Relative Susceptibility

to

Static Discharge

Damage

5-2

Rear

Interface

Connector

Assignments

Component

Reference

Chart

@

Component

Reference

Chart

@

OPERATORS

SAFETY

SUMMARY

The general

safety

information in this

part

of

the

summary is for both operating and servicing

personnel.

Specific

warnings

and

cautions will be

found

throughout

the

manual

where

they

apply,

but

may

not

appear

in

this

summary.

TERMS

In

This

Manual

CAUTION

statements

identify conditions

or

practices

that could

result

in damage

to

the

equipment

or

other

property.

WARNlNG

statements

identify conditions

or

practices

that

could

result

in

personal

injury

or

loss

of

life.

As

Marked

on

Equipment

CAUTION

indicates

a

personal

injury

hazard

not immediately accessible

as

one

reads

the

marking, or

a

hazard

to

property

including

the

equipment itself.

DANGER

indicates

a

personal

injury

hazard

immediate1

y

accessi

bleas

one

reads

the marking.

SYMBOLS

In

This

Manual

This

symbol indicates

where

applicable cautionary

or

other information

is

to be

found.

As

Marked

on

Equipment

/j

DANGER

-

High

voltage.

@

Protective

ground (earth) terminal.

ATTENTION - refer

to

manual.

vii

Power

Source

This

product is intended to operate in a power module connected

to

a

power source that will

not

apply

more than

250

volts rms between the supply conductors or between either

supply

conductor

and

ground. A protective ground connection by

way

of

the grounding conductor

in

the

power

cord

is essential for

safe

operation.

Grounding

the

Product

f

his product

is

grounded through

the

grounding conductor of the power module power cord.

To avoid

electrical

shock,

plug the power

cord

into a properly

wired

receptacle before

connecting to

the

product input or output terminals.

Upon

loss

of

the protective-ground

connection,

all accessible conductive

parts

(including knobs and controls

that

may

appear

to

be

insulating), can render

an

electric

shock.

Use

the

Proper

Fuse

To

avoid fire hazard, useonly the fusespecified in

the

parts list for your

product,

and

which

is

identical

in

type, voltage rating,

and

current rating.

Refer fuse replacement

to

qualified service personnel

Do

Not

Operate

in

Explosive

Atmospheres

To

avoid explosion,

do

not operate this product in

an

atmosphere of explosive gases unless

it

has been specifically certified for such operation.

De

Not

Remove

Covers

or

Panels

To

avoid personal injury,

do not

remove

the

product covers

or

panels.

Do

not operate the

product without

the

covers

and panels properly installed.

Do

Not

Operate

Without

Covers

To

avoid personal injury, do not

operate

this pr~duct without

covers

or panels installed.

Do

not

apply power to the plug-in

via a plug-in extender.

viii

SERVICING

SAFETY

SUMMARY

FOR

QUALIFIED

SERVICE

PERSONNEL

ONLY

Refer

also

to

the

preceding

Operators

Safety

Summary.

Do

Not

Service

Alone

Do

not

perform internal service or

adjustment

of

this

product unless

another

person capable

of

rendering first aid and

resuscitation

is present.

Use

Care

When

Servicing

With

Power

On

Dangerous

voltages

exist

at

several

points

in

this

product.

To

avoid

personal injury,

do

not

touch

exposed

connections

and

components while power

is

on.

Disconnect

power

before

removing protective

panels,

soldering,

or

replacing corn

ponents.

Power Source

This

product

is

intended to

operate

in

a

power

module

connected

to

a

power

source

that

will

not

apply

more

than

250 volts rms

between

the

supply

conductors

or

between

either supply

conductor

and

ground. A protective ground connection

by

way

of

the

grounding

conductor

in

the

power cord is essential

for

safe

operation.

Section

1-DM

505

SPECIFICATION

Introduction

The

DM

505

Digital M ultimeter measures

resistance,

dc

or

ac

voltage, and

dc

or

ac current.

The

AC

functions

respond

to

the average value of an

ac

current or voltage

and

the

readout displays the sinusoidal rms value. In the

resistance

mode

of

operation, the HI

n-LO

fi

pushbut-

ton selects either

of

two

full-scale

probe

tip voltages.

The

front panel

pushbuttons

select the functions and

ranges.

The

INPUT pushbutton selects front panel

con-

nector input

(

EXT)

for current, voltage

and

resistance

measurements, or

rear

interface

connector input (INT) for

voltage

and

resistance measurements.

The

readout is

a

3

1/2

digit display

using

seven-segment

LED.

The

decimal

point

is automaticaSly positioned

by

the range pushbut-

tons.

The polarlty signs for

dc

voltage and dc current

measurements are

also

displayed automatically.

A

blink-

ing display indicates overrange except

on

the

1000

Y

dc

and

500

Y

ac

ranges.

The

reading rate

IS

approximately

three readings per second.

Performance

Conditlons

The

electrical characteristics

are

valid only

if

the

DM

505

has been calibrated

at

an ambient temperature

between

+21°C

and

i-25"

C

and

is operating

at

an ambient

temperature between

O0

C

and

4-50"

C,

unless otherwise

noted.

Items listed

in

the Performance Requirements

column

of

the Electrical Characteristics are verif

led

by

completing

the Performance

Check

in

this manual. Items listed in the

Supplemental Information column

are not verified in this

manual.

They

areeither explanatory notes or

performance

characterist~cs for

which

no limits are specified.

ELECTRICAL

CHARACTERlSTlCS

Front Panel

Table

1-1

0C

VOLTMETER

Supplemental

information

Characteristics

Accuracy for the

200

mV,

2

V,

20

V,

200

V,

and

1000

V

ranges:

+I

8"

C

to

+28"

C

200

mV

to

200

V

ranges

1000

Y

range

Performance

Requirements

+(O.l%

of reading

+

0.05°h

of full

scale)

f

(0.1%

of reading

+

O.T%

of

full

scale)

O°C

to

+18"C,

+28"C

to

+50°C

200

mV

to

200

V

ranges

1006

V

range

Common

Mode

Rejection

Normal

Mode

Rejection Ratio

Maximum Resolution

Response Time

Input Resistance

it(0.2%

of

reading

+

0.1

%

of

full scale)

f

(0.2%

of reading

f

0.2%

of

full scale)

3100

dB

at

dc.

280

dB

at

50

to

60

Hz.

350

dB

at

50

and

60

Hz

k0.2

Hz.

Verified with

1

kR

unbalance at

the

LOW

terminal.

(Clock frequency:

20.48

kHz

tl%.)

1

00

pV

<0.5

second to rated accuracy.

f

0

Mfl

f

0.5%.

Table

1-1

(cont)

Table

1-2

AC

VOLTMETER

Characteristics

Maximum

lnput

Voltage

VOLTS/R

to

LOW

1-2

REV

A

OCT

1979

Performance Requirements

Supplemental

Information

1000

V

peak.

VOLTS/R to Ground

LOW

to

Ground

Supplemental Information

Charaderlstics

Accuracy

for

the

200

mV,

2

V,

20

V,

200

V

and

500

V

ranges:

+lBO

C

to

+28'

C

200

mV

to

200

V

ranges

45

Hz-10

kHz

sine

wave

25-45

Hz,

10-20

kHz

sine

wave

1000

V

peak.

1000

V

peak.

Performance

Requirements

f

(0.5%

of reading

+

0.1

%

of full scale)

f

(1%

reading

+

0.1%

of

full

scale)

500

V

range

25

Hz-10

kHz

sine wave

f

(1%

of

reading

1-

0.4%

of full scale)

0°

C

to

+18"

C,

+28"

C

to

4-50" C

200

mV

to 200

V

ranges

45

Hz-10

kHz

sine

wave

&(I%

of

reading

+

0.15%

of

full scale)

25-45

Hz,

1G20

kHz

sine

wave

f

(1.5%

of

reading

+

0.15% of

full

scale)

500

V

range

25

Hz-10

kHz

sine

wave

Common

Mode

Rejection

Ratio

Maximum Resolution

Response

Time

f

(1.5%

of reading

+0.6Oh

of

full scale)

250

dB

at

50

to

60

Hz.

Verified with

1

kR

unbalance

at

the

LOW

connector.

100

pV.

<1.5

seconds,

within

specified

accuracy

on

measurements

within

any

one

range.

Input

Impedance

Maximum

lnput Voltage

VOLTS/R

to

LOW

10

MR

+0.50J0

paraHeled

by

less

than

130

pF.

566Y

ac

rms

or600Vdc,

nottoexceed

1000

Y

peak.

VOLTS/fl

to

Ground

LOW

to

Ground

500

V

ac

rms

or

600

Vdc,

not

to

exceed

1000

V

peak.

500

V

ac

rms

or

600

Vdc,

not

to

exceed

1000

V

peak.

Maximum

Volt-Hz

Product

107

VaHz.

Table f -3

OHMMETER

f

f

8°C

to

+2a°C

200

R

range

200

R

range

pproximatel

y

f

6

V.

Table

1-4

PC

AMMETER

CharaeZerEstlcs

Accuracy

for

the

200

PA,

2

rnA,

20

mA,

200

rnA

and

2000

mA

ranges:

+lg°C

to

+2g°C

0°Cto+180C,+z80Cto+~~0C

Response

Time

Maximum

Open

Circuit

Input

Voltage

mA

to

LOW

Performance

Requirements

f

(0.3%

of

reading

+

0.05% of

full

scale)

f(O.4Y0ofreading+O.l%offullscale)

Supplemental

Information

<0.5

second.

250

V

peak.

TaMe

1-4

(cont)

Characteristics

Maximum

Floating

Voltage

mA

to

Ground

Low

to

Ground

Table

1-5

1000

V

peak.

1000

Y

peak.

Maximum Resolution

kC

AMMETER

Performance

Requirements

0.1

PA.

Accuracy

for

the

200

PA,

2

mA,

20

mA,

200

mA,

and 2000

rnA

ranges:

45

Hz

to

10 kHz

Response f ime

Maximum

Open

Circuit

Input

Voltage

Maximum

Floating Voltage

Supplemental

Information

ELECTRICAL

CHARACTERISTICS

Rear

Interface

fable

1-6

DC

VOLTMETER

Characteristics

Performance Requirements Supplemental

1nformatlon

Accuracy

for

the

200

mV,

2

V,

20

V,

200

V

and

1000 V ranges:

200

mV

to

200

V

ranges

1000

V

range

f

(Q.tYo

of

reading

+

0.05% of full scale)

f

(0.1%

of

reading + 0.1%

of

full

scale)

Table

1-6

(cont)

Supplemental

Information

200

mV

to

200

V

ranges

1000

V

range

f

(0.2%

of

reading

4-

0.1%

of

full

scale)

f

10.2%

of

reading

t

0.2%

ot

full

scale)

Maximum

Resolution

--

Response

Ti

rn

e

lnput

Resistance

<0.5

second

to

rated

accuracy.

Maximum

lnput Voltage

Pin

28B

to

Pin

28A

200

V

peak.

Pin

28B

to

Ground

200

V

peak.

Pin

28A

to

Ground

200

V

peak.

Table

1-7

AC

VOLTMETER

Performance

Requirements

Supplemental

Imformation

Charaderisttics

Accuracy

for

the

200

mV,

2

V,

20

V,

200

V

and

500

V

ranges:

200

mV

to

2

V

ranges

45

Hz-10

kHz

sine

wave

f(0.5%

of

reading

f

O.lP/o

of

full

scale)

25-45

HZ,

110-20

kHz

sine

wave

20

V

to

200

V

ranges

25

Hz-20

kHz

sine wave

f

(I0h

of

reading

+

0.1%

of

full scale)

+(lO/o

of

reading

+

0.I0/o

of full scale)

500

V

range

(max.

input:

200

V)

25

Hz-10 kHz

sine

wave

f

(1%

of

reading

-t

0.4O/o

of full

scale)

200

mV

to

2

V

ranges

45

Hz-10 kHz

sine

wave

25-45

Hz,

10-20

kHz

sine

wave

20

V

to

200

V

range

f

(1%

of

reading + 0.15%

of

full scale)

f

(1.5%

of

reading

+

0.15°h

of

full

scale)

25

Hz-20

kHz sine

wave

f

(1.5%

of

reading

+

0.1

Soh

of

full

scale)

500

Y

range

(max.

input:

200

V)

.

f

(1

-5%

of

reading + 0.6%

of

full scale)

25

Hz-10 kHz

sine

wave

Table

1-7

(cont)

Table

1-8

OHMMETER

+lB°C

to

+28OC

200

!J

range

200

fl

range

reading

$

0.15%

of

full

scale

Supplemental

Infwrnation

I00

pV

<I

.5

seconds,

within

specified

accuracy

on

measurements

within

any

one range.

200

V

peak.

200

V

peak.

200

Y

peak.

Characteristics

Maximum

Resolution

Response

Time

Maximum

l

nput

voltage

Pin

288

to

Pin

2814

Pin

288

to

Ground

Pin

28A

to

Ground

Maximum

Volt-Hz

Product

lo7

V~HZ.

Performance

Requirements

Table

1-9

MISCELLANEOUS

ENVIRONMENTAL

CHARACTERISTICS

Table

1-10

DM

505

ONLY"

Operating

Operating

i-30°C

and

+50°C

at

90%,

1-5

-O%I~

-T-28800B,

class 5 with

Operating

0.64

mrn

(0.025")

disp.,

5-55-5

H?

Test

to

MI L-t-28&00B, class

3.

(sine

wave)

75

min. total.

Non-operating

50 g (1/2

sine)

11

ms*

Test

to MIL-T-288OOB, class

3.

Operating

45O

or

4"

or

equilibrurn,"'

Test

to

M

l

t-T-28800B, class

3.

Supplemental

lnformatlon

Approximately

8

W.

Characteristics

Power

Consumption

Performance

Requlrements

Reading

Rate

Over-range

Cali

bration

Interval

Warm-up

Tirna

3

per

second.

Flashing display

(except

1000 V dc and

500

Y

ac

ranges).

fOOQ

hours

or

six

months, whichever

occurs

first.

30

minutes

(60minutesaFterstorage

in

high

humidity

environment).

Table

1-10

(cont)

'See

Table

1-11

for

system

envfronmental characterlstlcs.

Characteristics

E.M.C.

Operating

Electrical Discharge

Operating

Transportation

with

power

module.

Description

30

Hz

to

1

GHZ~

Test

to

MI

L-T-288008,

class

3.

20

kV

rna~.~

Charge applied to

each

protruding

area

of

the

product under test except the input

terminals.

Qualified under National

Safe

Transit
Association Preshipment Test Procedures,
Project

1

A-B-1

and

Project

t A-B-2.

'without

power

module.

d~ernperature:

Durlng

$ow

temperature

test

MIL-T-28800B,

paragraph

4.5.5.1.3(b)

for

dass

5,

steps

4

and

5

shall

be

per-

formed

before

step

2,

Also,

the

instrument shall not

be

operating

durhg

step

6,

paragraph

4.5.51.3(e),

class

5.

Whlle

aperating,

condensed

molsture

shall not

be

present

on

class

5

Instruments.

Drying

of

the

instrument

for

thFs

class

may

be

performed

in

a

suitable

chamber,

if

necessary.

CHumldlty: The

20

V

ac

and

200

Y

ac

ranges

shall

be

derated

to

f

25%

of

readlng

+2

counts.

Note:

All

performance

requirements

are

met

while

operating

at

w95%

relative humldlty

at

f

30°C

and

f

50°C

with

on

hour wnrmup.

Table

1-11

TM

500

SYSTEMS

I

Characteristics

Temperature

TM

501

TM

503

TM

504

TM

506

TM

515

Operating

Non-operating

Meets

same

test standards

as

plug-in.

Meets

same

test

standards

as plug-in.

Humidity

Operating Meets same Zest standards

as

plug-in.

Non-operating

Altitude

Meets

same

test standards

as

plug-in.

Operating

Meets

same

test standards as plug-in.

Non-operating

I

Meets

same test standards

as

plug-in.

PHYSICAL

CHARACTERISTICS

Table

1-12

TM

515

0.38

mm

(0.015

in)

disp.

10-55

Hz

(sine

wave)

75

min.

30

g

(1/2

sine)

11

ms,

18

shocks

CharacterlsUcs

TM

501

TM

503

TM

504

TM

506

Characteristics

Deswlption

Bench

Handling

Qperati

ng

Electrical

Discharge

Operating

Transportation

Vibration
Package

Drop

Finish

Net

Weight

Overall

Dimensions

Meets

same

test

standards

as

plug-in.

Meets

same

test

standards

as

plug-in.

Meets

same

test

standards

as

plug-in.

Meets

same

test

standards

as

plug-in.

VI

bration

Operating

Shock

Operating

Anodized aluminum panel

and

chassis.

2.2

I

bs

(exclusive

of

probes)

(1

kg).

2.m

in

(86.8

mm)

W X 11.240

in (285.3

mm) D X

4.961

in

(125.9

mm)

H.

0.26

mm

(0.01

0

in)

disp.,

j0-55

Hz

(sine

wave)

75

min.

total

20

g

(1/2

sine)

11

ms

18

shocks

Section

2-DM

505

OPERATING

INSTRUCTIONS

Installation Instructions

The

DM

505

is calibrated

and

ready to

use

when

received.

It

operates

in

one

compartment

of

a

TM

500-

series power module. Refer

to

the power

module

i

nstruc

tion manual

for

line voltage requirements and

power

module

operation.

Turn

the

power

module

off

before

inserting

the

plug-

in;

otherwise,

damage

may

occur

to

fhe

plug-in

drcuitry.

Check to

see

that

the

plastic barriers on the inter-

connecting

jack

of

the selected

power

module

compart-

ment

match

the cut-outs in

the

DM

505 circuit

board

edge

connector.

Align

the

DM

505

chassis

with

the upper

and

lower

guides

(see

Fig.

2-1)

of

the

selected

compartment.

Push

the

DM

505

in

and

press

firmly

to

seat

the

circuit

board

in

the interconnecting

jack.

Pull

out

the

power

switch

Qn

the

power

module.

One

or

more

characters

in

the

LED

display should now

be

visible.

To

remove the

DM

505,

pull

on

the

release

latch

(located

in

the

lower

left

corner)

until

the

i

ntereonnecting

jack

disengages and the

DM

505 slides

out.

Rg.

2-1.

DM

505

Installation

and

remova!.

CONTROLS

AND

CONNECTORS

DISPLAY

@

Display

3

1/2

digit

LED

readout with decimal point

auto-

matically positioned by

the

range pushbuttons.

VOLTS

Selects

dc

voltage function.

@VOLTS

AC

pushbutton

Selects

ac

voltage function.

RESISTANCE

@

kn

pushbutton

Selects resistance function,

Pushbutton

In

selects full scale probe

tip

voltage

of

0.2

V

in all ranges. Pushbutton

out

selects full scale

probe

tip

voltage

of

2

V

except

in the

200

R

range

which is

0.2

V.

CURRENT

Selects dc current function.

@m~

AC

pushbutton

Selects

ac

current function.

CONNECTORS

A

Refer to Input Connections in theoperating Instruc-

tions.

@

mA

Connector

Use

with

LOW

input connector for current

measurements.

@

LOW

Connedw

Common input

connector

for all measurements.

@

voLTwn

Connector

Use

with

LOW

input

connector

fw

voltage

and

resistance measurements.

@

Ground

Binding

Post

Chassis ground.

RANGE

SELECTION

@

Range

Select

Pushbuttons

Select

the

desired measurement range.

@

Release

Latch

Pull

to

remove plug-in.

@

IN

PUT

EXT- I NT

Pushbunon

Refer

to

Input Connections

in

the

Operating Instruc-

tions.

Pushbutton

out

{EXTI

selects front

panel

input con-

nectors;

pushbutton

in

(INTI selects rear interface

input

terminals for

dc

and

ac

volts

and

resistance

measurements only.

OPERATORS

FAMILIARIZATION

General

Operating

lnf

ormation

With the DM

505

properly installed

in

the

power

module, allow thirty minutes warmuptimefor operation

to

specified

accuracy. Select

the

desired measurement f unc-

tion

and

range.

When

the

value

of

the

quantity

being

measured

is

unknown,

setect

the highest

range first.

Decrease

the

range

setting

until the display blinks to

indicate over-range. Then

change

the range pushbutton

to the

next

higher range. This method obtains

maximum

resolution.

1

WARNING

)

To

avoid

shock

hazard

from

voltages

measured

by

the

DM

505:

I,

Avoid

all

contact

with

the

voltage

source

being

meas

wed.

2.

Disconnect

probes

from

circuit

undertest

before

disconnecting

probes

from the

DM

505,

or

before

removing

the

DM

505

from

the

power

module.

Operating Instructions-DM

505

cor

Fig.

2-2.

Front panel controls and connectors.

Input

Connections

A

DC

Current

Measurements

The INPUT EXT-INT pushbutton selects front panel

or

rear Interface input.

Three input connectors provide front panel measure-

ment connections. The

YOLTS/Tr

and

LOW

input connec-

tors are used for

ac

or dc voltage

or

resistance

measurements.

The

mA and LOW input connectors are

used for

ac

or

dc

current measurements. Rear interface

pins 28B

(HI)

and

T8A

(LO) are used for rear interface

voltage and resistance measurements.

Norml

rneasure-

rnent conditions

are

with the

LOW

terminal ungrounded.

A

connection between the

LOW

input connector and the

ground terminal may be made to

referencetheinput tothe

DM

505

chassis

ground.

Use

caution,

as

the Lowterminal

is then connected

ta

earth ground through the power

module three-wire

power

cord. False readings may

be

obtained due to ground loops.

The

maximum

input

voltage

is

I

kV

peak

at

the

front

panel

connectors and

200

Y

peak

at

the

rear

inter-

face

connectors.

The

front

panel

VOLTSIfl

and

LOW

connectors

may

be

floated

at

I

kVmaximum

above

ground.

fhe

rear

input

connector

200

V.

Sine-wave

Response

The

DM

505

responds to the average value

of

an

ac

or

dc current or voltage and the readout displays the

sinusoidal rms value. The effective or rms

value

of a sine-

wave

is

0.707 times the peak voltage or current.

The

average

value

is

0

636

of

the

peak

value. The scale factor of

the

DM

505 is 0.636/0.107 or 0.9.

To

obtain the average

value

of

a

sinusoidal input voltage or current, multiply the

DM

505

readout

by

0.9.

'DC

Voltage

Measurements

Press the VOLTS

DC

pushbutton and an appropriate

range button. Apply the voltage to be

measured

to

the

LOW and

VOLTS/n

input connectors. 0 bserve

the

max-

imum input voltage ratings

as

indicated on the front panel.

The readout displays

a

f

if the input to the VOLTS/R

connector

is

positive with respect to the

LOW

input

connector.

A

-

is

displayed

if

the input

at

the

LOW

input

connector

is

the more positive. With the

LOW

and

VOLTS/n input connectors shorted, the display reads

zero

+

one count.

Press

the

mA

DC

pushbutton

and

an appropriaterange

button. Connect the

dc

current to

be

measured tathe

LOW

and

mA

input connectors. Conventional current flowing

into the

mA

connector and out

of

the

LOW

connector

(or

electron

flow

into the

LOW

connector and out

of

the mA

connector) indicates

a

+

on the display. The input

resistance in the current mode is listed in Table

2-T.

Table

2-1

AC

Voltage

and

Current

Measurements

CURRENT

MODE

INPUT

RESISTANCE

For ac voltage measurements, press the VOLTS

AC

pushbutton and an appropriate

range

button. Connect

the

unknown voltage

to

the LOWand VOLTS/R input connec-

tors.

Range

200 PA

2

mA

20

mA

200

mA

2000

mA

To measure

ac

current,

press

the

rnA

AC

pushbutton
and an appropriate range button. Connect the unknown
ac current

to

be measured to the

mA

and

LOW

input

connectors. The input resistance in

the

current mode

is

listed in Table 2-1.

Approximate

Resistance

1001

R

100.4

R

10.25

R

1.2

R

0.25

R

Resistance

Measurements

Press the

kfl

pushbutton and

an

appropriate

range

button.

Also,

press

the

HI

n-LO

fl

button for

a

maximum

full-scale probe-tip voltage

of

0.2

V.

Release the HI n-LO

R

button

(out

position) for a maximum full-scale probe-tip

voltage

of

2 V (except on the

200

fl

range which is

0.2

V).

The

low probe-tip voltage is

useful

for

making

in-circuit

measurements without forward-biasi ng silicon diodes or

transistor junctions.

The

kR

mode

provides an accurate constant current

at

the

LOW

and VOLTS/n input connectors. Refer to Table

2-1

for the value

of

current and maximum voltages across

the input terminals for full

scale

display readings (instru-

ment

not

over-ranged). The maximum (open circuit)

voltage available from the

YOLTS/fl terminal to the LOW

terminal

in

the

resistance

mode

is about

+6

V.

REV

A

OCT

1979

Operating

rnstructions-DM

505

Ta'ble

2-2

If

the Tektronix instrument is

to

be

shiw~ed

to

a

. .

OHMMETER

SOURCE

CURRENT

AND

VOLTAGE

Tektronix

Service Center

for

service or repair, attach

a

tag

showing owner

(with

address) and the name

of

an

Packaging

Information

individual

at

your firm

that

can

be

contacted. Include

the

complete instrument serial number and a description of

the

service required.

Save

and

re-use

the

package

in which your i nstrurnent

was

shipped. If

the

original packaging

is

unfit

for

use

or

not available, repackage

the

instrument

as

follows:

Surround

the

instrument with polyethylene

sheeting

to

protect the finish of

the

instrument. Obtain

a

carton

of

corrugated cardboard

of

the

correct

carton

strength

and having

inside dimensions

of

no

less

than 6 inches

more

than the instrument dimensions. Cushion the

instrument

by

tightly packing 3 inches

of

dunnage

or

urethane foam between carton and instrument on

all

sides.

Seal

the

carton with shipping tape or

an

in-

dustrial stapler.

A

list

of

standard aecessaries

(and

part numbers)

is

The

carton

test

strength

for

this instrument is

200

located

in

the Replaceable Mechanical

Parts

list.

pounds

per square inch.

Section

3-DM

505

THEORY

OF

OPERATION

The

basic circuitry

of

the

DM

505

consists

of

an analog-

to-digital

(AID)

converter, display decoders and drivers,

a

clock,

and

power supplies (see the Block Diagram in the

Diagrams section at the back

of

this

manual). These

sections form

a

digital voltmeter that

measures

1.999 Vdc

full

scale.

A gain switch in the

AID

converter allows

measurement

of

199.9

mV

full scale.

An

attenuator

enables

measurement of

19.98,

199.9,

and 1000

Vdc

full

scale.

Ac

voltages are measured by passing the input

signal through

a

precision rectifier circuit

that

converts

ac

voltages to dc (an

ac

converter). Resistances are

measured

by

forcing a known current

from

the

ohms

converter through

the

unknown resistanceand measuring

the voltage across the unknown resistance.

Low

resistance current shunts permit measurement of

ac

and

dc currents.

NOTE

In

the

following

descriptions,

the

mond

by

each

tjtle

refers

to

the

circuit diagram in

the

Diagrams

manual.

numbered

dia-

,

corraspondrng

section

of

this

Attenuator

and

Input

Switching

@

With the

INPUT

EXT-INf pushbutton

in

the EXf

position,

the

input

is

measured at the front panel connec

tors. Resistances and voltages are measured between the

VOLTS/R

and

LOW

connectors

and

current

is

measured

between the

mA and

LOW

connectors.

In

t

he

I

NT

position,

switch

S3

A,8

selects

the input at rear interface pins

288

(HI) and

28A

(LO)

for rear interface measurement

of

resistances and voltages. Thef ront panel input impedance
is

10

MR

paralleled

by

less than

100

pF.

The

VOLTS/R and

LOW

input connectors are con-

nected across

R1312, a voltage divider.

An

input measured

from

thejunction

of

R13$2A

and R1312B

is

attenuated by

a

factor of

100.

On

the 1 kVdc scale,

the

input is measured

from

the

junction

of

R1312B and R1312Cand isattenuated

by a factor of 1000.

Capacitors

C1312,

C1313,

and

C1311

compensate

the

attenuator for accurate

ac

signal

measurement. Capacitor

GI313 is

adjusted

at

10

kHzfor

a

flat frequency response.

One

solder-in shield and two additional shields

at-

tached just inside the

side

covers

shunt

stray capacitance

across the attenuator to ground when measuring floating

ac

voltages.

AC

Converter

@

In the

VOLTS

AC

mode, dc input voltages are blocked

by

capacitor C2114.

The

input

of

U1321 is protected

against excessive input voltages

by

R1424, CR1421, and

CR1422.

Ac

signals

are

buttered by unity gain amplifier

U1321 and applied to the active rectifier circuit U1211,

which

has

high-speed diodes, CR1221 and CR1222, in the

feedback loop. Thiscircuit configuration eliminatesthe

dc

voltage drop of the diodes.

The

half-wave rectified

ac

is

filtered

by

three-pole filter R1221, '21222, R1222, C1211,

Ri220,

and C1221 to provide ripple-free

dc

voltage

to

the

A/D

converter.

The

active rectifier and filter respond

to

the

average

value

of

an ac signal,

but

the

circuit gain is

calibrated to produce

a

dc

output equivalent

to

the rms

value of

a

a1

ne-wave input.

The

basic

gain

of the

ac

converter is adjusted by

R1322

for the

2

Yac

range

and

R1323 fine-trims the gain for

200

mVac

range.

l ntegrated circuit U1211

has

feed-

forward compensation provided by

C1212,

Ct

213,

and

R1216 to obtain

maximum

bandwidth,

Both the 20

Vac

and

200

mVac

ranges

use

U1211 at again

10

times the gain

on the

ot

her ranges. The

500

Vac range

connects

R1423

as

an additional attenuator

to

accommodate larger input

voltages.

Dc

feedback for U1211

is

provided by the

network

consisting

of R1223, R1224, and C1223.

Dc

offset

for

U12t

1

is

provided

by

R1321, the

AC f ERO

ADJ.

Ohms

Converter

@

The ohms converter consists of precision current

source

01 31 1

and

floating current mirrar U1311 (see Fig.
3-1). Transistor Q1311 generates a relatively low
temperature coefficient current,

by

mirroring the voltage

from

Zener diode VR1211 across R1215 and R1213.

The

current at

the

collector

of

Q1311 E is approximately

i

rnA

and is adjusted by R1213, the

HI

fl

ADJ.

This

reference

current

from

Q1311 B appears at the inverting terminal

of
U1311. The output of Q1311 sources current through
R1304 to stabilize the reference current. In the HI

R

position, the output

of

U1311 is elevated 10 V above its

input. In the

LO

R

position,

S2-H

connects R1305 and

R1413 in parallel with R1304, lowering the

output

voltage

of

U1311 and reducing thereferencecurrent to U1311 pin

2

by

a

factor of 10. Table 3-1 lists the values

of

source

current for the resistance ranges in the HI

il:

and LO

R

positions. Resistor R1413 adjusts the

LO

reference

current to one-tenth

of

the

HI

Cl

reference current.

Theory

of

Operalton-DM

505

I

>

to

A/D

Converter

curred-Wing

reQstance

n

PROTECTOR

~1312 131412

CR1302

VOLTSlR

OS1410

unknown

ISOURCE

CRf

SO1

resistance

+5

V R1304

LOW

tll

R

I

mA

lr

ci

26924

J

Fis

3-1.

Simplified diagram

ol

the

ohms converter.

Table

3-1

OHMS

CONVERTER

SOURCE

CURRENT

AND

MAXtMUIYI

FULLSCALE

VOLTAGE

.I

unknown

reslstame

x

R

current

setting

resistance

9

unknown

resistamce

x

R

range.

%I1201

has

1OX

galn.

Swltch

Positions

LO

Sl

LO

n

LO

12

LO

R

LO

R

HI

R

HI

n

HI

R

HI

R

HI

R

Range

---

200

flc

2

k~'

2Q

kRG

200

kQc

2000

kRc

200

RE

2

kn

20

kR

200

kR

2000

kR

Current-Setting

Resistance

I

Through

Unknown

Resistance

10

kR

10

kn

100

kR

1

MR

10

Mfl

10

kR

10

kn

100

kR

1

Mfl

10

MR

V

Across

Current

Setting

Resistance'

V

Across

Unknown

Resistance

(Full-S~ale)~

1

mA

100

PA

10

PA

1

PA

0.1

pA

1

mA

1

m~

100

PA

10

PA

1

PA

10

V

tv

1

V

f

V

1

V

10

V

10

v

10

V

10

V

10

V

0.2

V

0.2

v

0.2

V

0.2

V

0.2

V

0.2

V

2v

2V
2V

2V

Theory

of

Operation-DM

505

The output voltage of

U1311

is applied across sections

of

the

attenuator

R1312

(and

R1412for

the

200

kn range)

which

serves

as a current setting resistance. The voltage

across

R1312

and

R1412

is equal to

the

voltage

across

R1304.

The current through

R1312

flows through lamp

DS1410

and out

the

VO

LTS/R terminal through the

unknown resistance. The range switches select sections

of

the attenuator

so

that different values of current can

be

sourced out

of

the VOLTS/I1 terminal.

The

voltage

developed across the unknown resistance

is

then

measured by the

ASD

converter.

Diodes

CR1301

and

CR1302

and

lamp

DSt4lO

protect

the

ohms converter from

excessive

dc

and

ac

input

voltages. If

an

excessive voltage is applied to a resistance

range, the voltage is clamped by

CR1302

and

GR1301

and

appears across lamp

PS1410.

As

the filament

of

DS1410

warms

up,

the rmistance of thefilament increases, limiting

the current through the diode clamps.

DS1410

is rated

to

handle

125

V

rms indefinitely and

250

V

rms for a Fimited

time. Voltages in

excess

of these ratings cause

DSI410

to

act

as a

fuse. Diode

CR1301

also limits

the

open

circuit

voltage

at

the VOLTS/R input connector to approximately

+6

V.

Current

Shunts

@

The

current shunts in the

DM

505

consist of

R1425,

Rl426,

and t hick-film resistor network

R1521,

connected

between

the

mR

and LOW input terminals.

These

resistors

convert the input current to

a

voltage for measurement by

the

DM

505

circuitry. The maximum full

scale

voltage

developed across the current shunts

at

the

maximum full

scale current

is

0.2

volt. In the

dc

current mode, this

voltage is switched directly to the

ND

converter. In the ac

current

mode,

the current shunt voltage is first routed

through the

ac converter. The current shunts

are

protected by the diodes in

CR1621.

If

the

voltage across

the current shunts exceeds approximately

1.2

V,

the

diodes in

CR1621

begin

conducting, shunting current
around the resistors. The maximum voltage drop across
the current shunts in

an

overload condition is

ap-

proximately

1.5

V.

An input current exceeding

2

A opens

fuse

F1521.

The

DM

505

measures

voltages

up to

1

kV

peak above

chassis

ground

(200

V

peak above ground

at

the rear

interface input). Isolation

is

accomplished with power

transformer

Tl001,

which is powered from

the

25

Vac

floating windings

13A

and

138

of the power module.

Transformer

Kl 001

converts the

25

Vac to a secondary

output of

47

V

rrns, center-tapped, across pins

7

to

9,

and

12

V

rms across pins

lOto 12.

The 47 Y rms is rectified

by

CR1111

and filtered by capacitors

C1012

and

Clll

f

to

provide approximately + and

-

26

V

unregulated. The

positive voltage across

ClOl2

is

regulated

to

+15.75

V

by

U1022,

and

shunt resistors

R1122

and

R1021.

Resistor

R1021

adjusts the output voltage

for

the

minimum

+15.75

V required for proper ohms converter operation.

The

negative

voltage

across

Cllll

is

regulated to

-12

V

by

Uf 121.

The

current pulled from

each

of these supplies

is approximately

40

rn

A.

Capacitor

C1021

equalizes un-

balanced capacitance between the secondary windi ngs of

T1001,

pins

7,

8, and

9.

Capacitor

C1021

reduces any

60

Hz

common

mode

signal appearing between the front

panel input terminals of the

DM

505

and chassis ground.

The

12

V

rrns

from the secondary

of

TI

001,

pins

10

to

12,

is rectified

by

CRfOll

to provide approximately

+I2

Y

unregulated to the display anode drivers. The

+12

V

across

ClOf

I

is regulated to

+5

V

by

U1021.

Clock

9

The clock signals for

U1303

are generated

by

U1301,

a

free-running multivibrator

wit

h

a

frequency determined by

C1203, R1205, R1204,

and

R1202.

CLOCK

FREQ

ADJ

R1202

sets the clock frequency to

20.48

kHz,

a

multipEe

of

the

line frequency. Components

of

50

Hz or 60 Hz

at

the

input terminals are rejected since they

are

of

equal

magnitude during the up and down portions

of

the

measurement cycle,

Analog

to

Digital Converter

@

Integrated circuit

U1201

comprises

the

analog section

of the analog-to-digital

(#D)

converter

and

U1303

con-

tains the necessary control logic.

The

A/D

converter in the

DM

505

operates

on

the charge balancing principle. The

input voltage is converted to

a

current that charges

capacitor

Cf 101

in an integrator circuit. Charging con-

tinues until the capacitor voltage crosses afixedthreshold
level. Then

a

reference current larger than

the

maximum

input current

is

subtracted from the input current and the

capacitor discharges until

the

threshold level is crossed

again. This process

is

repeated until the measurement

interval is over. During the measurement interval,

a

counter in

U1303

accumulates clock pulses from clock

generator

U1301

when only the input signal

is

applied to

the integrator,

and

subtracts clock pulses

when

both the

input

signal and the reference current are applied to

the

integrator, resulting in a net count proportional to the
input voltage. This conversion occurs in

U1201

and

is

controlled

by

U1303.

Refer

to

Fig.

8-2

in the Diagrams

section.

Integrated circuit

U1201

also contains automatic zero-

ing

circuitry. Between meaurement intervals, the input of

U1201

is

switched to ground and an auto-zero voltage,

related

to

the offset voltages

in

U1201,

is stored across

auto-zero capacitor

C1102.

This auto-zero voltage is

converted to

a

current and subtracted from the input

current

at

the integrator

so

that errors due to

offset

Theory

of

Operalion-DM

SO5

voltages and ground offsets are compensated.

The

reference voltage for

U1201

is

supplied

by

a

temperature

stable diode,

VR1201.

Resistors

R1111

and

R1112

(the

2

Vdc

ADJ)

convert the

reference

voltage

to

a

reference

current

for

the integrator, The gain of the integrator is

switchable from

one

to

ten

by

placing

R1210,

R1211,

and

R1301

in parallel with

R1212.

This gain increases

the

integrator input current derived from the input signal by

a

factor

of

ten. Resistor

R1210

allows the total parallel

resistance

to

be

closely trimmed for proper

gain

for the

200

mVdc

range. Resistor

R1113

and

low-leakage diodes

CR1113

and

CR1112

provide input protection for

U1201.

Capacitor

C1201

and resistor

R1113

increase the normal

mode rejection

of

U1201.

Transistor

Q1201

and

DC

ZERO

ADJ

resistor

R1104

set the dc zero of

Ut201,

Integrated

circuit

U1201

receives commands from

U1303

via two

digital linescalled "measure-zero"

(U1201,

pin

3)

and

"up

down"

(U1281,

pin

4).

The

"up-down" line controls the

direction

of

counting and integration.

The

"'measure-

zero" line determines whether

the

input

of

U1201

receives

the input signal or is connected

to

ground. Integrated

circuit

U1201

provides an output

to

U1303

through

a

"comparator" line

(U1201,

pin

5).

The comparator line

signals the counter in

U1303

when

the integrator has

passed the threshold. The outputs

of

U1303

control the

d~splay through

the

display driver circuitry.

A

detailed description

of

the operation of the

A/D

converter follows.

The

20.48

kHz clock frequency from

U1301

is divided

by

the time

base

counter

into

groups

of

6144

pulses.

Measurement takes place

for

4096

of

these

pulses and

automatic zeroing

takes

place for

2048

pulses.

During

the

auto zero interval, the input of the buffer

amplifier is grounded.

The

buffer offset current also

offsets the

output

of

the integrator.

The

offset

at

the

integrator output passes through

R1103

to

the

plus input

of the auto-zero amplifier.

The output

of

the

unity gain

auto-zero amplifier compensates for this offset current at

the summing node (pin

9)

at the integrator input. The

reference current through

Rl

f

11

and

R1112

from the
reference voltage source is applied for four clock cycles
and disconnected for the next four cycles by the

U/D

control logic. The reference current is connected to

R1112

when the updawn logic is low. Equilibrium

for

the

entire

integrating

and

auto-zero system is obtained when the

sum

of

the average currents at the integrator summing

junction

equals zero. Capacitor

GI102

charges to the

equilibrium voltage and maintains this

voltageat

the

auto-

zero amplifier input during

the

measurement interval

when the switch from the integrator output is

open.

See

Fig.

3-2

for functional timing during theauto-zerointerval.

The

fifty percent

duty

cycle

of

the

up-down

counter

is

overridden

at

the

start of

the

auto-zero interval. This

override period permits the output of the integrator to

come

to

V,, and

Cf

102

to

assume this

voltage.

Fig.

3-2.

Auto-zero

timing intervals.

I

d

.

YOVERRiDE

r

1

AUTO-ZERO

-

U/D

I

I

1

COMPARATOR

I

I

1

I

1

INTEGRATOR

OUTPUT

2692-5

Theory

of

Operation-DM

505

Upon completion of the

2048

clock pulse auto-zero

interval,

the

measurement interval commences.

The

measure-zero logic switches the analog input voltage to

the

buffer

input and disconnects the integrator

output

from the auto-zero amplifier input.

The

additional current

resulting at the summing junction of theintegrator

causes

the integrator output voltage to

move

away from the

equilibrium voltage obtained during auto-zero interval

and

maintained during the measurement interval

by

C1102.

The

comparator senses and transmits this devia-

tion to

the

control logic.

The

control logic changes the

duty cycle of

the

reference voltage in

an

attempt

to re-

establish equilibrium at the integrator summing

junctfon.

The

up-down logic

is

"up" (integrator output voltage is

also

up)

for

one

clock

cycle

and

"down" for seven cycles

when the comparator output

was high during the

preceding set of eight

clock cycles.

This

is

shown

as

duty

cycle

A

in Fig.

3-3.

When

the

comparator output is

low

in

clock cycle

seven,

the up-down logic

is

up

for

seven

cycles

and down for

one

cycle during the following eight clock

cycles.

This

is

shown

as

duty cycle

B.

Figure3-3 showsthe

result

of

these actions on the integrator output.

A

counter in U1303, synchronous with

the

up-down

logic, increments by

each clock pulse when the up-down

logic is

"up"

and

decrements

by

each

clock pulse when

the up-down

Iogic

is

"down".

The

net

count increases

by

six

counts

for each B duty cycle and decreases by six

counts for

each

Aduty cycle, toa maximum count

of

about

3100.

This

counting procedure is reversed

for negative

input voltages.

The

polarity

of

the input voltage is determined by the

state

of

the

updown

logic

when

the bcd counter state is

zero. This information

is

stored in a flip-llop and

loaded

into

the

static latch Once

each

measurezero cycle.

The bcd counter accumulates a number of counts
proportional to the input voltage during the measure
interval

while

the

control logic works

to

maintain

equijibrium. Equilibrium is achieved in

steps

and usual1 ya

residual voltage remains

at

the

end

of the measurement

cycle.

This

residual voltage is Compensated for by a short

override interval at

the

beginning

of

the auto-zero period.

The

counter

continues

until the integrator output equals

the auto-zeroequilibrium voltageand the up-down logic is

"down".

The

bcd

counter is

now

put

on

hold and its

contents

Zoaded into the latches. The counter

is

then

cleared and

the

multiplexer sends the measurement

result, digit

by

digit,

to

the

output

data

buffers.

Display

Driver

Circuitry

@

Integrated circuit

U1301,

pins

13,

14,

15,

and 16,

provides

bcd

output of digits

in

parallel form, multi;plexed

by digit.

The

bcd digit signals are decoded by

U1501

and

applied

to

the cathodes

of

seven-segment

LED

Uf

002,

U1101,

and U1102.

The

segments of these LED are

connected

in parallel

to

U1501. Digit strobesfrom U1303,

pins

7,2,3,

and 4 are inverted by U 1302

A,

B,

C,

and D and

applied to the anodesof the

LED

by Q1402, Q1403, Q1404,

CLOCK

INPUT

CYCLETO

r2

345s

70

12345s

71

9

Z~~SB~O

12

34s

et

o

MI'

u/a

4-

MEASURE

INTERvM

c"Y"CyE

LdAA&

B-1

COMPARATOR

I

I

I

INTEGRATOR

OUTPUT

VS~RG

269M

Fig.

3-3.

Measurement

Interval

timing.

Theory

of

Operation-DM

505

and Q1405.

The

segment

information at

the

cathode

of

each

LED

is displayed

as

its anode is strobed high.

The

display

is strobed

in

the

following

order:

digit

1,3,2,

and

4.

Digit

f

is

the

least

significant and digit 4 is

the

most

significant (1

or

0). The

digit strobes are also routed

through

sections

of

the

range switches

to providedecimal

point

information to

the

display. Transistor

Q1507

con-

trols the most signifFcant digit, U1001.

The

sign

is enabled

by

switches

S2K

and

S2B,

which

connect

thesign

anodes (t11001

pins

1,6,and7) to+12

V.

The

cathode

of

the

negative

segment

of

the

sign (pin

4)

is

hard-wired

low

through

R1601.

The

sign

of

the

input

from

U1303,

pin

5,

is

buffered through U1302Etothe

cathodes

of

the

positive

segments

of the

sign

(U1001,

pins 3 and

5).

If

the

sign

has

been

enabled

by

S2K

or

S2B, a positive

sign

will

be

displayed

when

pins

3

and 5 are low.

CALIBRATION

PROCEDURE

lntroductlon

Test

Equi

pent

Requirements

This section consists of a Performance Check which

Below

is

a

list

of

equipment required to verify operation

verifies the electrical specifications

listed in Section

1,

and

as specified Other equipment

may

be

substituted when

an Adjustment procedure which provides

a

sequential suitable.

adjustment

of

internal controls. This procedure should

be

used

to

restore

the

instrument performance

to

the etec-

trical specifications listed

En

Section

1

of

the manual.

Table

4-1

LIST

OF

TEST

EQUIPMENT

REQUIREMENTS

Description

TM

500

Pawer

Module

Periormance

Requirements

Dc

voltage

accuracy

check

fluke Model

341A

Voltage

source within

f

0.01%

De

common

mode

rejection check Cali brator

2

Ydc

range adj ustrnent

200

mVdc

range adjustment

Applications

All

steps

Ac voltage
source

Example

TEKTFIONIX TM

501,

TM

503,

TM

504,

TM

506

OV

to

500

Vrms,

25

Hz

to

20

kHz,

within

50.05%

Ac

voltage

accuracy

check

Dc

common mode rejection check

Dc

normal

mode rejection check

Ac

common

mode

rejection check

2

Vac

range

adjustment

200

mVac

range

adjustment

10

kHz

ac

adjustment

---

Resistance

standard

Dc

current source

Ac current source

1

kS2

resistor

Fluke Model

5200A

Ac

Voltage

Cali brator and

Fluke

Model

521

5A

Power

Amplifier

Ohms

accuracy

check

HI

fl

adjustment

LO

i2

adjustment

pppp

Dc

current accuracy

check

o-

Ac

current

accuracy

check

Dc

common

mode

rejection check

Ac common

mode

rejection check

---

+15.75

V

supply adjustment

Clock frequency adjustment

0

R

to 2 Mn,

within

f

0.05%

0

A

to

2

A,

within

f

0.0Ph

0

A to

2

A,

45

Hz to

10

kHz,

within

f

0.15%

3%

tolerance,

1

J8

watt

Electro Scientific Industries
Model

DB62

Decade Resis-

tance Box

Valhalla

Scientific

Inc.

Model

2500

AGDC

Cur-

rent

Cali

brator

Same

as

for

dc

current

Tektronix Part

No.

321-01

93-00

f

EKTRONIX

DM

501

A,

DM

502,

DM

502A

TEKTRONIX

DC

504, Digital

Counter

Voltmeter

Counter

0

to

+20

V,

1

mW

resolution

20.48 kHz, within

&0.25%

Calibration

Procedure

(Performance

Check)-DM

505

Table

4-1

(cont)

on

mode rejection

check

tronix

Par!

No.

c

common

mode rejection

check

Tektronix

Part

No.

dual

banana

Dc

normal

mode

rejection

check

Tektronix

Pad

No.

01

3-007&00

connector

I

ea

bnc

female

to

clip

lead

adapter

2

ea

coaxial

cable

with

bnc

connectors

Tektronix

Part

No.

01 2-0057-01

Ac

common

mode

rejection

check

Ail

accuracy

checks

Dc

common

mode

rejection

check

Ac

common

mode rejection

check

1

ea

dual

banana

shorting

bar

Cable

50

n

irn pedance

Dc

zero

adjustment

Ac

zero

adjustment

For

connection

to

instrument

under

test

Adjustments

Clock

frequency

adjustment

Tektronix

Part

No.

067-0645-02

Tektronix

Part

No.

01

0-61

01-01

Calibration Procedure (Performance

Check)-DM

505

PERFORMANCE

CHECK

Introduction

2.

Install

theDM

505inthepowermoduleandconnect

This procedure

checks

the electrical characteristics

of

the power module and test equipment

to

the line voltage

the

DM

505

that appear

in

the Specification portion

of

this

source.

manual. If the instrument fails

to

meet

the

requirements

given

in

this

Performance Check, the Adjustment

procedure should

be

performed.

3.

Turn

on

the power module

and

all test equipment

and

allow

at

least

30

minutes

for

warm-up

(60

minutes

after

storage in

a

high

humidity environment).

The

electrical characteristics in this section

are

valid

only if the

DM

505is calibrated at anambienttemperature

between

+21°C

and

+25"C

and operated at

an

ambient

temperature between

0'

C

and

f

50°C.

Tolerances that are specified in this Performance

Check apply

to

the instrument under test and

do

not

include test equipment

error.

For

convenience,

many

steps in this procedure check the performance

of

this

instrument

at

on1

y

one

value

in

the

sgecif

ied

performance

Dangerous

voltages

may

be

encounfered

in

the

following

sfeps.

Caution

must

be

exercised.

Do

not

contact

the

output

connectors

of

the

voEtage

calibrator,

the

input

terminals

of

the

DM

505

or

the

jnternal

circujtry

of

the

DM

505.

The

knobsetscrews

of

soma

voftage

calibrators

have

Been

known

to

be

af

a

high

voltage

potential;

check the

setscrews with

a

voltmeter

before

handling

the

knobs.

range. Any value, with appropriate limits, within the

FRONT

PANEL

PERFORMANCE

CHECK

specified range may

be

substituted.

PROCEDURE

For the following sections

of

the Performance

Check,

set

the

INPUT

EXT-INT pushbutton

to

the

out

(EXT)

If

the

rear interface input

is

to

be

used,

the rear interface

position.

accuracy specifications for

ac

and

dc

voltages and

resistances may

be

checked using

aTM

500-series Option

2

power

module. Instructions and accuracy tables for rear

1-

Check

the

~c

voltage

Accuracy

interface performance check are given following this
procedure.

a.

Set the

dc

voltage calibrator to

0 V and connect the

dc

voltage calibrator through the

necessary

adapters

and

the

50

R

coaxial cable to the

VQLTS/R

and

LOW

input

connectors.

Preliminary

Procedure

1.

Ensure

that

all

power

switches

are

off

and that the

b. Press

the

VOLTS

DC

button

and

set

the calibrator

power module

and

all test equipment are adapted for the

voltages and the

DM

505

range pushbuttons

as

listed in

line

voltage

available. Table

4-2.

TaMe

4-2

DC

VOLTAGE

ACCURACY

DM

505

Range

Button

200

mV

2

V

20

V

200

V

1000

V

Dc

Calibrator

Display

Umlts

Voltage

+IS0

C

to

3-28"

C

0

to

+lB°C,

+2a°C

to

+50°C

pp

180.000

mV

1.80000

V

18.0000

V

180.000

V

1000.00

V

179.7

to

180.3

1.797

to

1.803

17.97

to 18.03

179.7

to

180.3

998

to

1002

179.4

to

180.6

1.794

to

1.806

17.94

to

18.06

179.4

to

180.6

996

to

1004

Calibration

Procedure

(Performance

Cheek)-DM

505

c.

CHECK-that the

DM

505

display reads within

the

g

Check

Common

Mode

Rejection

(PC

Mode)

limits

for

the

ambient temperature

as

listed

in

Table

4-2.

a.

Connect

the

bnc female

to

dual banana

connector

to

the

VOLTS/R

and

LOW

connectors.

d.

Set

the

dc

calibrator output voltage to

0

V

and

disconnect it from

the

DM

505.
b. Connect

the

bnc male to dual binding

post

connec-

tor to

the

bnc

female

connector attached to

the

DM

505

front panel.

2

Check

Ac

Voltage

Accuracy

a.

Set

theacvoltagecalibrator to0 Vandconnectthe

ac

voltage calibrator

(and

power ampiifier,

as

needed)

to

c.

Connect

the

1

kR

resistor between the binding

the

VOLTS/R

and

LOW

input CQnneCtOrS through the

posts on the dual binding post connector.

coaxial cable

and

necessary adapters.

b. Press the

VOLTS

AC

button, Press

the

range

d.

Connect the red clip lead

of

the

bnc

female

to

clip

buttons and set

ac

calibrator voltage

and

f

requenc~

as

lead adapter to

the

red binding

post

and

the

black

cli

p lead

listed in Table

4-3.

to

the

DM

505

ground binding post.

c.

CHECK-that the

DM

505

display reads within the

e.

Connect the

bnc

female connector through

a

coax-

limits

tor

the

ambient temperature

as

listed in Table

4-3.

ial cable

to

the dc voltage calibrator.

d.

Set

the

ac

calibrator output voltage

to

0

Y

and

disconnect it from the

DM

505.

f.

Press

the

VOLTS

DC

and

200

mV

pushbuttons.

Table

4-3

AC

VOLTAGE

ACCURACY

45

Hz-1

0

kHz

1.779

to

1.821

17.79

to

18.21

Calibration

Procedure

(Performance

Check)-DM

505

g.

Set

the

dc

voltage

calitxator

for

an

output

of

100

Vdc.

d.

Connect

the

red

clip

lead

of

the

female

bnc

to

clip

lead adapter

to

the

red binding post

and

the

black

clip lead

to

the

DM

505

ground binding post.

h.

CHECK-that the display reads

G01.0.

e.

Connect

the

female

bnc connector through

a

coax-

ial

cable

to

the

ac

voltage calibrator.

i.

SetthedcvoltagecalibratortoOVBndreconnectthe

coaxial cable

to

the

ac

voltage calibrator.

f.

Press

the

VOLTS

AC

and

200

mV

pushbuttons.

j.

Set

the

acvoltage calibrator

for

an

output

of

50

Vac

rms

ai

50

to

60

Hz.

g.

Set

the

ac

voltage

calibrator for

an

output

of

5

Vac

rms

at

50

Hz

to

60

Hz

+0.2

Hz.

k.

CHECK-that

the

display

reads

G7.2.

h.

CHECK-that

the maximum

display

reading is

G22.4.

I.

Set

the

ac

voltage calibrator

output

to

0

V

and

disconnect it from the

DM

505.
i.

Set

the

ac

voltage calibrator output to

0

V

and

disconnect it from the

DM

505.

NOTE

If

the

DM

505

does

not

display

the

correct

readings

as

stated

in

step

3

parts

h

and

k,

perform

Clock

5.

Check

Normal

Mode

Rejection

(Dc

Mode)

Adjustment

of

the

Adjustment

procedure

andrepeat

the

above

Common

Mode

Rejection

Check

(Dc

a.

Connect

the

bnc

female

to

dual

banana

connector

Mode).

to the

VOLTS/R

and

LOW

connectors.

b.

Attach the

bnc

connector through a coaxial cable to

the

ac

voltage

calibrator.

4.

Check

Common

Mode

Rejection

(Ac

Mode)

c.

Press the

VOLTS

DC

and

200

mV

pushbuttons.

a.

Connect

the

bnc female

to

dual banana connector

to

the

VOLTS/R

and

LOW

connectors.

d.

Set

the AC Calibrator for 0.224V AC at 50Hz *0.2Hz

or

60Hz *0.2Hz.

b.

Connect the bnc male to dual binding post connec-

tor

to

the

bnc

connector

attached to

the

DM

505

front

e.

CHECK-that the maximum display reading

is

panel.

G

1.0.

c.

Connect

the

1

kR

resistor

ktween

the

binding

f.

Set

the

ac

calibrator output

to

0

V

and

disconnect it

posts

on

the

dual

binding

post

connector.

from the

DM

505.

REV A OCT

1979

Caribratlion Procedure

(Performance

Check)-'DM

505

6.

Check

Ohms

Accuracy

a.

Connect

the resistance

standard

to the

VOLTS/Rl

and

LOW

connectors.

b.

Press

the

kf2

pushbutton.

Make

each measurement

in

thefollowing

tablewith the

HI

!2-LO

R

button

in

the

LO

(in)

and

the

HI (out) positions.

c.

CHECK-that

the

display

reads within the limits

for

the

ambient tern

perature

as

listed

in

Table

44.

d.

Remove

all

connections

to

the

DM

505.

7.

Check

PC

Current

Accuracy

a.

Connect the

current

calibrator

output

through

a

coaxial cable

and

necessary

adapters tot

he

mA

and

LOW

connectors.

Connect

the

dc

voltage

caPibrator

output

through

a

coaxial

cable

and

adapters

to

the

current

calibrator

input.

b.

Press

the

rnA

DC

button

and

set

the

DM

505

range

buttons

and

current

source

output

as

listed

in

Table

4-5.

c.

CHECK-that

the

display

reads

within

the

limitsfor

the ambient

temperature

as

listed in Table

4-5.

d.

Set

the dc current

source

to

0

A

and

disconnect

it

from

the

DM

505.

Table

4-4

OHMS

ACCURACY

I

I

Table

4-5

Range

Button

200

n

DC

CURRENT

ACCURACY

--

Standard

180.000

n

DM

505

Range Button

200

pA

2

mA

20

mA

200

m

A

2000

mA

.

.

%lB°C

to

+2a°C

178.8

to

181.2

Dc

Current

Source

180.000

pd

1.80000

mA

18.0000

mA

180.000

mA

1800.00

mA

0

to

S18"C,

f28"C

ta

+50°C

177.9

to

182.1

Display

Umlts

4-18' C to

f

28"

C

179.4

to

180.6

1.794

to

1.806

17.94 to

18.06

179.4 to

180.6

1794

to 1806

0

to

+18OC,

+2BDC

to

+50°C

179.0

to

181.0

1.790

to

1.810

17.90

to 18.10

179.6

to

181.0

1700

to

1810

Calibration

Procedure

(Performance

Check)-DM

505

8.

Check

Ac

Current

Accuracy

a.

Connect

the

current calibrator outpul through

a

coaxial cable

and

the

necessary

adapters

to

the

mA

and

LOW

connectors. Connect

the ac

voltage calibrator

output

through

a

coaxial

cable

and

adapterstathe current

calibrator input.

b,

Press

the

mA

AC

button

and

set

the

DM

505

range

buttons

and

the

Current

source

output,

as

shown in Table

4-6,

at any frequency from

45

Hz

to

10

kHz.

c.

CHECK-that

the

display reads within the limits

for

the

ambient temperature

as

listed in Table

4-6.

d.

Set the current source to

0

A

and disconnect it

from

the

DM

505.

REAR

INTERFACE

PERFORMANCE

CHECK

PROCEDURE

f

o

verify instrument accuracy of resistance

and

ac

and

dc

voltage

modes via

the

DM

505

rear

interface,

followthe

steps outlined

in

the Performance

Check

procedure

for

the

f

ront

panel input, but apply voltages and resistances to

rear interface pins

28B

(HI)

and

28A

(LO).

Access

to

the

rear

interface

input

pins

28A

(LO)

and

28B

(HI)

is

most

easily

made

using

a

TM

500-series

Option

2

power

module. Press the

INPUT

EXT-INT pushbutton (INT

position) to select rear interface input. Substitwte Tables

4-7, 4-8,

and

4-9

for

the

appropriate

tables

listed

in

the

Performance

Check

procedure.

NOTE

The

inprrf

cable

fixture

from

the

calibrating

sources

to

the

rear

interface

pins

will

have

fo

be

modified

to

accommodate

accuracy

checks

via

the

rear

interface.

Table

4-6

AC

CURRENT

ACCURACY

Table

4-7

DC

VOLTAGE ACCURACY

FOR

REAR

INTERFACE

DM

505

Range

Button

-

200

pA

2

mA

20

mA

200

m

A

2000

m

A

Ac

Current

DM

505

Range Button

200

rnV

2

Y

20

V

200

V

1000

V

(max.

input

200

V

peak)

Display

Umits

Dc

Calibrator

Source

4-18"

C

to

-t2e°C

O

to

+18OC,

+28*

C

to

+50°

C

pppp

Display

LFmits

180.000

pA

1.80000

mA

18.0000

mA

180.000

rn

A

1800.00

mA

Volt

age

180.000

mV

1.80000

V

18.0000

V

180.000

V

180.000

V

178.5

to 181.5

1.785

to

1.815

17.85

to 18.15

f

78.5

to 181.5

1785

to

1815

177.5

to

182.5

1.775

to

1.825

17.75

to

18.25

177.5

to

182.5

1775

to

1825

+I

8O C to

+28O

C

179.7

to 180.3

1.797

to

1.803

17.97

to

18.03

179.7

to

180.3

178 to

182

0

to

+lR°C,

+28"C

to

-1-50°C

179.4

to

180.6

1.794 to 1.806

17.94

to

18.06

179.4 to 180.6

177

to

183

Callbratlon

Procedure

(Performance

Cheek)-DM

505

Table

4-8

AC VOLTAGE

ACCURACY

FOR

REAR INTERFACE

10

kHz-20

kHz

f

.?80

to

f

,820

1.770

to

1.830

fable

4-9

OHMS

ACCURACY

FOR

REAR

INTERFACE

OM

505

Range

Button

200

R

2

kR

20

kn

200

kfl

2000

kfl

Resistance

Standard

180.000

R

1.80000

kfl

1

8.

OQOQ

kfl

180.000

kR

1800.00

kR

Display

Llmlts

+I

8"

C

to

+2B0

C

178.1

to

181.9

1.789

to

1.811

17.90

to

18.10

179.0

to

181.0

'I790

to

1810

0

to

+lB°C,

+2R°C

to

i-50°C

177.3

to

182.7

1.781

to

1.819

17.82

to

18.18

178.2

to

181.8

1786

to

1819

Callbration

Procedure

(Adjustments)-DM

505

ADJUSTMENTS

Introduction

PROCEDURE

This procedure need

not

be

performed

unless

the

instrument fails

to

meet the performance requirements

of

I-

Adiwt

the

+15m7S

the electrical characteristics listed in the Specification

a.

Set

the voltmeter to the

20

Vdc

range.

section. Adjustment

is

generally required after a repair

has

been made or after long time intervals

in

which normal

aging

of

components

may

affect instrument accuracy.

b. Connect the voltmeter positive lead to the DM

505

H5.75

V

tea point

and

the negative lead to

TP1521

(LO).

To

ensure instrument accuracy, check

the

calibration

every

1000

hours

of operation or

every

six

months if used

c.

EXAMINE-that the voltmeter reads

+15.75

Vdc

infrequently.

f

0.08

V.

Tektronix, I

nc.

provides complete instrument repair

d.

ADJUST-R1021,

the+15.75 V ADJ,for avoltmeter

and

calibration at local Field Service Centers

and

at

the

reading

of +15.~5

v

f0.05

V.

Factory

Service Center. Contact your local Tektronix Field

Office

or

representative for

further

information.

e.

Disconnect the voltmeter from the

DM

505.

Test

Equlpmeml Required

2.

Adjust

the Clock

Frquency

Test equipment used for adj ustrnent of the

DM

505

is

a.

Set the counterto Frequency,

10

Hz

Resolution, and

listed

in

the beginning of the Calibration

section.

All test

Display

Time

fully

ccw.

equipment is assumed to

be

correctly calibrated

and

operating within specifications.

b.

Connect the counter input lead

to

the

CLK

test

point.

A

XI

probe

may

be

used,

if

desired.

Preparation

Connect

the

DM

505

to the power module via the

flexible

plug-in extender.

To

gain

access

to

the

ad-

justments,

remove

the left side cover

of

the

DM

505

by

pulling the

rear

of the side cover

outward

from

the

instrument. Then remove the large

metal

shield attached

to

a

standoff in

the

center of

the

instrument. If desired,

most

adjustments may be made through the holes in

the

metal

shields using an insulated adjustment tool. Adjust-

ment locations

are

shown in the illustration located in

the

pullout

pages

at

the

rear

of

this manual.

Connect the test equipment

and

the

power

module to

a

suitable line voltage source. Turn on the

power

module

and the test equipment;

allow

at

least

30

minutes far

equipment

warm

up

and

stabilization. Set the

INPUT

EXT-

INT to the out

(EXT)

position.

Make

adjustments at an

ambient temperature

of

+21°C

to

+25*C.

Perform

ad-

justments in the order given, since

some

adjustments

interact with others. Interactions

are

noted

in the

procedure.

Refer

to the adjustment location

page

(in the

Diagrams and

illustrations

section).

c.

EXAMINE-that the counter reads

20.68

kHz

to

20.28

kHz.

d.

ADJUST-R1202,

CLOCK

FREQ

ADJ,

for a fre-

quency of

ZQ.48

kHz

rt0.05

kHz.

e.

Disconnect the

counter.

3.

Adjust

Oc

Zero

a.

Press the

VOLTS

DC

button and the

200

mV range

button.

b.

Short

the

VOLTS/n

and

LOW

input connectors

together with the dual

banana

plug

shorting bar.

c.

EXAMINE-that the

DM

505

display reads

00.0

rto.

1.

Callbratlon Procedure (Ad1ustmenls)-DM

505

d. ADJUST-R1104, DC

ZERO

ADJ,

for a display

5.

Adjust

the

200

mVdc

Range

reading

of

00.0

M.

a.

Set

the

dc

voltage calibrator to 0.190

V.

e. Press the

2

V

range

button.

b.

Press the VOLTS

DC

button and the 200

rnV

range

button.

f.

EXAMINE-that the

DM

505

display reads .000

40.001.

c.

Connect

the

voltage calibrator positive lead to the

VOLTSJQ connector

and

the

negative lead to the

LOW

g.

ADJUST-R1104

for

a

display

reading

af

.000.

connector.

NOTE

d.

EXAMINE-that

the

DM

505

display reads 190.0

f

0.3.

Best

results

will

be

obtained

with

R1104

set

mid-way

in

the

range

for

which

both

the

200

mV

and

2

V

DC

scales

read

0.

e.

ADJUST-R1210,

.2

VDC

ADJ,

for a reading

of

190.0

310.1.

h.

INTERACTEON-this adjustment

affects

the

AC

VOLTMETER

zero and most other f ull-scale adjustments.

f.

INTERACTION-this adjustment

affects

the

200

mVac

and

LO

R

range adjustments.

i.

Disconnect the

short

between

the

VOLTS/R and

LOW input connectors.

4. Adjust

the

2

Vdc

Range

g.

Set

the voltage calibrator output

to

0

Y

and dis-

connect it from the

DM

505.

a.

Press the

VOLTS

DC

button

and

the

2

V

range

button.

6.

Adjust

the

HI

R

b.

Set

the

dc

voltage caFibrator

to

1.900

Y.

a.

Press

the

k!2

button, the HI

R

button

and

the

2

kR

range

button.

c.

Connect

the

calibrator positive

lead

to

the

VOLTS/R

b,

Set

the resistance standard

to

1.900

kn.

connector

and

the

negative lead

to

the

LOW

input

connector.

c.

Connect

the resistance standard

to

the

VOLTS/R

and

LOW

input connectors.

d. EXAMINE-that the

DM

505

display reads 1.900

d.

EXAMINE-that the

DM

505

display reads

1.900

*0.011.

e. ADJUST-R1112, the

2

YDC

ADJ,

for

a

display

reading

of

1

900

&0.001.

e.

ADJUST-R1213, the HI

fl

ADJ

for a display

readlng

of

1.900

f

0.001.

f. I NTERACTI ON-this adjustment

affects

the

200

mV

dc range, the HI

and

LO

n

and

both

AC V

range

adjustments.

f. INTERACTION-this adjustment

affects

the

LO

R

range adjustment.

g.

Set

the

dc

voltage calibrator output

to

0

V

and

disconnect it

from

the

DM

505.

g.

Continue

to

the

next

step.

Callbration Procedure (Adjudments)-DM

505

7.

Adjust

the

LO

fl

a.

Press

the

kR

button, the

LO

Cl

button

and

the

2

kfl

range button.

c.

Connect the

ac

voltage calibrator to

the

VOLTS/il

and

LOW connectors.

d. EXAMINE-that the

DM

505

display reads

1.900

*0.012.

b.

EXAMIiq4E-that the

DM

505

display reads

1.900

*

0.01

1.

e.

ADJUST-R1322, the

2

VAC

ADJ,

for

a

display

reading

of

1

.W0

3.0.001.

c.

ADJUST-Rl413,

the

LO

R

ADJ, for a display

reading

of

1.900 f 0.001.

d,

Disconnect

the

resistance standard.

8.

Adjust

the

Ac

Zero

a.

Press the VOLTS

AC

button, and the

200

mV

range

button.

f,

INTERACTION-this adjustment

affects

the

200

mVac

and

10

kHz

ac

adjustments.

g.

Set

the

ac

voltage calibrator output to

0

V

and

disconnect it from

the

DM

505.

10.

Adjust

the

200

mVac

Range

a.

Press

the

VOLTS

AC

button and

the

200

mV

range

b. Short the

VOLTS/R and LOW input

connectors

button.

together

using

the dual banana plug

shorting

bar.

b.

Set

the

ac

voltage calibrator to

0,190

Vac

at

100

Hz.

e.

EXAMINE-that

the

DM

505

display reads

00.0

*

0.2.

c.

Connect

the

ac

voltage calibrator to the

VOLTS/R

and

LOW

input

connectors.

d.

ADJUST-R1321, the AC

ZERO

ADJ,

for

a

display

reading

of

00.0.

Wait about

three

seconds

and verify the

reading, d. EXAMINE-that the

DM

505

display

reads

190-0

f

1.2.

e.

Press the

2

V

range

button.

e.

ADJUST-R1323, the

.2

VAC

ADJ,

for a display

f.

EXAMINE-that the

DM

505

display reads .000

reading

of

lKLO

*

20.002.

f.

I NTERACTION-this adjustment affects the 10

kHz

g.

ADJUST-R1321 for a display

reading

of .000.

ac

adjustment.

h.

INTERACTION-this adjustment

affects

the

g.

Set

the

ac

voltage calibrator output to

0

V

and

200

mYac

and

2

Vac

range adjustments.

disconnect it from the

DM

505.

i.

Disconnect the

short

between the

VOLTS/n

and

11.

Adjust

the 10

kHz

Ac

LOW i n

put

connectors.

Remove

the right side

cover

from

the

DM

505.

Perform

this adjustment with both side shields on the instrument

9.

Adjust

the

2

V

Ac

Range

using a plastic adjustment tool with a small

metal

blade.

a. Press the VOLTS

AC

button and

the

2

V

range

button.

a.

Connect

the output ground terminal

of

the

ac

voltage calibrator to

the

DM

505

LOW input

connector.

Connect the output

HI

termlnal

of

the calibrator to the

b.

Set

the

ec

voltage calibrator to

1.900

V

at

100

Hz.

DM

505

VOLTS/n input connector.

Calibration

Procedure

(Adjustments)-DM

505

b.

Press

the

VOLTS

AC

button

and

the

20 V range

button.

c.

Set

the

ac

voltage calibrator

to

19.00

V

at

a

trequen-

cy

of

10

kHz.

d.

EXAMINE-that

the

DM

505

display

reads

19.00

f

0.12.

Verify

the reading with

the

adjustment

tool

remov-

edfrorn

the

DM

505.

e.

ADJUST-C1313,

the

10

kHz

AC

ADJ,

for a

display

reading

of

19-00

f

13.01.

C1313

is

made

of

glass

and

is

fragile.

Do

not

turn

the

slug

past

its

stop.

f.

Set

the

ac

voltage calibrator

output

to

0

Y

and

disconnect

it

from

the

DM

505.

Section

5-OM

505

MAINTENANCE

There

are

no special preventive maintenance proced-

ures that apply to the

DM

505.

Refer

to

the

power module

instruction manual for general preventive maintenance

procedures and instructions.

Tektronix,

Inc. provides

complete

instrument repair

and calibration

at

local Field Service Centers and

at

the

Factory Service Center. Contact

your

local Tektronix Field

Office or representative

for

further information.

Recali

bration

To ensure accurate measurements, check

the

calibra-

tion

of

this instrument after each

f

000

hours

of

operation

or every six months

if

used infrequently. In addition,

replacement

of

components

may

necessitate recali bration

of

the

affected

circuits.

Complete

adjustment instructions

are given in

the

Calibration section.

Obtaining Replacement

Parts

Most electrical and mechanical

parts

can

be

ordered

through

your

local Tektronix field office or representative.

However, you should be able

to

obtain

many

of the

standard electronic components from

a

local commercial

source

in

your area. Before

you

purchase or order

a

part

from

a

source other than Tektronix, I nc., please

check

the

electrical

parts

list for

the

proper value, rating, tolerance,

and

description.

Ordering

Parts.

When ordering replacement partsf rom

Tektronix,

Inc., it is important

that

all

of

the rollowing

i nforrnation

be

included

to

ensure receiving the proper

parts.

1,

lnstrument type (include modification or option

numbers).

2.

Instrument serial

numbc

3.

A

description of the

part

(i

lectrical, indude circuit

number).

4.

Tektronix

part

number

Heat

Sink

Removal

and Replacement

Use a screwdriver

or

other suitable

tool

to spread

the

spring tabs holding

UIM1

in

the heat sink.

Use

care not

to

spring the tabs beyond their elastic limit. Remove

the

regulator. Reverse

this

procedure to install the heat sink.

After replacing the

heat

sink,

make

certain the heat sink

firmly grips

U

t021,

to

ensure adequate

heat

dissipation.

Troubleshooting

Aids

Troubleshooting

Charts.

As

an

aid

in

locating problem

areas, troubleshooting charts are provided for

the

DM

505.

These

charts

are

located in the foldout

pages

in

the

Diagrams and Illustrations section.

Diagrams. Complete circuit diagrams

are

located

in the

foldout

pages

in the Diagrams

and

Illustrations section.

The

portions

of

the

circuit mounted on circuit boards

are

enclosed

by

a

solid

line.

The

circuit number

of

each

component in this instrument is

shown

on a diagram.

See

the

first page

of

the Diagrams and Illustrations section f or

definitions

of

the symbols and reference designators

used

on

the diagrams.

Circuit Board

Illustrations. In conjunction with each

circuit diagram

is

a

circuit board illustration.

Each

compe

nent shown on a diagram

is

also identified

on

the

circuit

board illustration by its circuit number.

Atable is provided

with

each

diagram listing components

by

circuit number.

The

table

also

lists the component grid locations

on

both

the

diagram

and

circuit board illustrations.

Adjustment

Locations

Illustration.

To

aid in locating

test

points and adjustable components,

the

adjustment

locations pullout page (normally

used

with the Adjust-

ment procedure) permit rapid location

of

test points and

adjustments.

Troubleshooting

Equipment.

Before

using

any

test

equipment to

make

measurements

on

staticsensitive

components or assemblies,

be

certain that any voltage or

current sup

flied by the test equipment

does

not

exceed

the limits of the component to

be

tested.

Staticsensitive

Components

rZx.7

8.

Avoid handling components in areas that

have

a

floor or work-surface covering capable

of

generating

a

static charge.

Static

discharge

can

damage

any

semiconductor

component

in

this

instrument.

9.

Use

a

soldering

iron

that

is

connected

to

earth

ground.

This

instrument contains electrical

components

that

are

susceptible to

damage

from static discharge.

See

10.

Use

only special antistatic

suction

type or wick

Table

5-1

for relative susceptibility of

various

classes of

type

desoldering tools.

semiconductors. Static voltages

of

1

kV

to

30

kV

are

common

in

unprotected environments.

Observe

the

following precautions to avoid damage:

RELATIVE

SCJSCEPTlBlLlTY

TO

STATIC

DISCHARGE

DAMAGE

1,

Minimize handling

of

static-sensitive components.

I

Relative

2.

Transport and store static-sensitive components or

Semiconductor

Classes

3.

Discharge

the

static voltage from

your

body

by

wearing

a

wrist strap while handling these components.

Servicing

staticsensitive assemblies or components

should

be

performed on1 y at a static-free

work

station by

qualified

service

personnel.

Level

sa

on conductive

foam.

Label

any

package that contains

or

discretes,

or

linear

static-sensitive assemblies or components.

microcircuits with

MOS

inputs.

(Most Sensitive)

4.

Nothing capable of generating or holding a static

charge should

be

allowed on

the

work station

surface.

assemblies in their original containers, on a metal

rail,

or

1

5.

Keep the component leads

shorted

together

whenever possible.

8.

Pick

up components bythe

body,

never

by

the

reads.

7.

Do

not slide the components over

any

surface.

ECL

Schottky signal diodes

*voltage

equivalent

for

levels:

1

=300to

500V

4=

500V

?=4(rOto

$000

V

(est.]

2

=

200

to

500

V

5

=

400

to

600

Y

8

=

900

V

3

=

250 Y

6=600fo800V

9=

1200V

(Voltage discharged

from

a

100

pF

capacitor

through

a

reslstance

of

100

ohms.)

2

3

--

Schottky

TTL

Hig

h-frequency

bipolar transistors

JFETs

Linear

microcircuits

Low-power

Schottky TTt

4

5

-

6

7

8

Section

6-DM

505

OPTIONS

None

available

at

this

time.

Section

7-DM

505

REPLACEABLE

ELECTRICAL

PARTS

PARTS

ORDERING

INFORMAT

ION

Replacement

parts are avaltable from or through your local

Tektronlx,

Inc. Field Office or representative.

Changes to Tektronix instruments are

sometimes

made

to

accommodate improved components

as

they become

available,

end

to

give

you the benef~t

of

the latest clrcvlt Improvements

developwd in our engineering department. It is therefore impor-

tant,

when ordering parts, to include the following Information

in

your order:

Part

number, instrument type or number, serial

number,

and

modification number

if

appl~cable.

!S

a

part

you have ordered

has

been

replaced with a new or

improved

part,

your local

Tektronix,

tnc.

Field Offlceor rapresen-

tative will contact you concerning any change in

part

number.

Change information,

if

any,

is

located at the rear of this

manual.

LIST

OF

ASSEMBLIES

A

list

Of

assemblies can be found at the beginning

of

the

Electrical Parts List. The assemblies are listed in numerical

order.

When

the

completecomponent number of

a

part

is

known,

this list

will identify the assembly in

which

the

pert

is located.

Only

the circuit number

will

appear on

the

dlagrams

and

circuit

board

illustrations.

Each

dlagram and circutt board
illustration is clearly marked with the assembly number.
Assembly numbers are also marked

on

the

mechanical

exploded

views

located in

the

Mechanical

Parts

List The component

number

is

obtained by adding

the

assembly number prefix to the

circuit number.

The

Electrical

Parts List

Is

divided and arranged by

assemblies In numerical sequence

(e.~.,

assembly

A1

with

Its

subassemblies

and

parts,

precedes assembly

A2

with its

sub-

assemblies

and parts).

Chassis-mounted parts have no assembly number prefix

and

are

located at the

end

of

the

Electrical

Parts

Llst.

TEKTRONIX-PART

NO.

(column

two

of

the

Elect

rid

Parts

List)

lndicates

part

number

to

be

used

when

ordering

replace-

ment part from Tektronix.

CROSS

INDEX-MFR.

CODE

NUMBER

TO

SERIALJMODEL

NO.

(columns

three

and

four

MANUFACTURER

of

the Electrical

Parts

List)

The

Mfr.

Code

Number to Manufacturer index

for

the

Column three

(3)

indicates the

serial

number at which

the

Electrical

Parts

List

is

located immedlately

after

this

page. The

part

was

first used. Column four

(4)

indicatest heseriat number

at

Cross

Index

provides codes, names

and

addresses

of manufac-

which the

part

was

removed. No serial number entered indicates

turers of components listed

In

the Electrical

Parts

List.

part is

good for all serial numbers.

ABBREVIATIONS

Abbreviatrons conform to American National Standard

Y7.1.

NAME & DESCRlPTlON (column

five

of

the

Electrical

Parts

List]

COMPONENT

NUMBER

(column

one

of

the

Electrical

Parts

List)

A

numbering method

has

been

used

to Identify assemblies,

subassern blies and

parts.

Examples of this numbering

method

and typfcal expansions are illustrated

by

the

fol lowlng:

E~ample

a.

component number

A23R1234

A-

Circuit number

Read:

Reslstor

1234

of

AssemMy

23

component number

/

h

.

-

-

A23A2R1234

A23

~1234

Assembly //imTircuit
number

nurn

ber number

In the Parts List, an ltem

Name

IS

separated from the

description

by

a

colon

(:)

Because

of

space

limitations, an ltem

Name

may

sometimes appear

as

Incomplete. For further ltem

Name

identification,

the

U.S.

Federal Cataloging

Handbook

H6-1

can be utilized

where

possible.

MFR.

CODE

(column

six

of

the

Electrical Parts

List)

Indicates the

code

number of

the

actual manufacturer of the

part.

(Code

to

name

and

address

cross

reference

can

be

found

immediately after

this page.)

MFR.

PART

NUMBER

(column

seven

of

the

Electrical

Parts

List)

Read:

ffeslstor

f234

af

Subassembly

2

of

Assembly

23

Indicates actual manufacturers part number.

Replaceable

Electrical

Parts-DM

505

Mfr.

Code

CROSS

INDEX-MFR.

CODE

NUMBER

TO

MANUFACTURER

Manufacturer

SANGAMO

ELECTRIC CO.,

S.

CAROL1

NA

DIV.

ALLEN-BRADLEY

COMPANY

GENERAL

ELECTRIC

COMPANY,

SEMI-COWDUCTOR

PRODUCTS

DEPARTMENT

MOTORO'A,

INC.,

SEMICONDUCTOR

PROD.

DIV.

ELECTRO

CUBE

INC.

ILLIMOtS

TOOL

WORKS,

INC.

PAKTROM

DIV.

CADDOCK

ELECTRONICS

INC.

CORNING

GLASS

WORKS,

ELECTRONIC

COMPONENTS DIVISION

HONSANTO

CO

.

,

ELECTRONIC

SPECIAL

PRODUCTS

MATSUSH'ITA

ELECTRIC,

CORP.

OF

AElERICA

GETTXG

ENG.

AND

PIFG.

COMPANY

NICHXCON/AMERICA/CORP.

SPRAGUE

ELECTRIC

CO.

BUSSMAN

MFG.,

DIVISION

OF

MCGMW-

EDXSON

GO.

CHICAGO

MINIATURE

LAMP

WORKS

ERIE

TECHNOLOGICAL

PRODUC.TS,

INC

.

BECKMAN

INSTRUMENTS,

XNC.,

HELIPOY

DXV.

JFD

ELECTRONICS

COKPOWENTS

CORP.

TEKTRONIX

,

INC

.

RADIO

UATERXALS

COWANY,

DIV.

OF

P.R.

MALLORY

AND

COMPANY,

INC.

DALE

ELECTRONICS, INC

.

Address

P

0

BOX

128

1201

2NO

STRBET

SOUTH

ELECTRONICS

PARK

5005

E

HCDOWELL

RD,PO

BOX

20923

1710

S.

DEL

MAR

AVE.

900

FOLLIN

LANE,

SE

3127

CHICAGO

AVENUE

550

HIGH

STREET

3400

HXLLVXEW

AVENUE

1

PANASONIC

WAY

PO

BOX

85,

OFF

ROUTE

45

6435

N

PROESEL

AVENUE

2536

W.

UNIVERSITY

ST.

4433

RAVENSWOOD

AVE.

644

W.

12TH

ST.

2500

HARBOR

BLVD.

PINETREE

ROAD

P

0

BOX

500

4242

W

BRYN

MAWR

P.

0.

80X

609

City,

State,

Zip

PICKENS,

SC

29671

MILWAUKEE.

BI

53204

SYRACUSE,

NY

13201

PHOENIX,

AZ

65036

SAM

GABRIEL,

CA

91776

VIENNA,

VA

22180

RIVERSIDE,

CA

92507

BRADFORD,

PA

16701

PAL0 ALTO, CA

94304

SECAUCUS,

NJ

07094

SPRING

MILLS,

PA

1687'5

CHICAGO,

IL

60645

NORTH

ADhMS,

MA

01247

ST.

LOUIS,

MO

63107

CHICAGO,

It

60640

ERIE,

PA

16512

FULLERTON,

CF.

92634

OXFORD,

NC

27565

BEAVERTQN,

OR

97077

CHXCAGO,

IL

60646

COLUMBUS,

NE

68601

REV

A,

OCT

1979

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000

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-C-d33

Replaceable

Elecfrtcal

Parts-DM

505

Tektronix SeriallModel

No.

Comoonent

No.

Part

No.

Eff

Dscont

Name

&

Descriation

Mf

r

Code

lvlfr

Part

Number

All

DISPLAY

CKT

BOARD

ASSY

CKT

BOARD

AS

SY

:

DISPLAY

80009

670-6014-00

KES.,FXD,CMPSN:308

OHM,SX,0.25W

01121

CB3015

RES.,FXD,CMFSN:'JOO

OHM,S%,0.25W

01121

C83015

LAMQ,LED

RDOUT:ORANGE,6

SEG,+/-1

50522

MAN

4605

LAMP,LED

RDOUT:DRANGE,7

SFG,0.4

DIGTT

50522

MAN4610A

L.AMP,LED

RDOUT:ORANGE,7

SEG,0.4

DIGIT

50522 MAN4410A

LAIMP,LEP

RDOUT:ORANGE,7

SEE,0.4

DIGIT

50522

MAN4610A

REV

A,

OCf

I979

DIAGRAMS

AND

CIRCUIT

BOARD

ILLUSTRATIONS

Symbols

Graphic symbols and class designation letters

are

based on

ANSI

Standard

Y32.2-1975.

Logic

symbology

is

based

on

ANSI

Y32.14-1973

in
terms of positive logic. Logic symbols depict the logic
function performed

and

may differ from the rnanufac-

turer's data.

The

overline on a signal name indicates

that

the signal

performs its intended function when it

is

in the

low

state.

Abbreviations are

based

on

ANSl

Y1.1-1972.

Other

ANSl

standards that are used in the preparation

of

diagrams

by

Tektronix, Inc. are:

Y14.15,

1966

Drafting Practices.

Y14.2,

1973

Line Conventions and Lettering.

Y10.5,1968

Letter Symbols for Quantities Used in
Electrical

Science

end

Elect

rieal

Engineering.

American National Standard Institute

1430

Broadway

Mew

York,

New

York

10018

Corn

ponent

Values

Electrical components

shown

on the diagrams are in

the following units unless noted otherwise:

Capacitors

=

Values

one

or greater are in picofarads

(pF).

Values less than

one

are in microfarads

IPF).

Resistors = Ohms

(R).

The

lollowlng

special

symbols

may

appear

on

the

dlagrams:

Functlon Block Tftle

Internal

Screwdriver

Adjustment

Cam Switch
Cbsure

Chart

(C-m

lndlcates

switch

closure)

Etchad

Circuit Board

Outlined in Black

Refer to

Wavewrm

Function Block
Outline

Test

voltaae

Heat Sink

Board

Name

PIO-Pan

Of

circuit

board

Assembly Number
Teklmnix Part

No.

for

circuit

boards

Assembly

Numbers

and

Grid

Coordinates

Each assembly in

the

instrument is assigned

an

assembly number

(e.g.,

A20).

The assembly number

appears on the circuit board outline

un

thediagrarn, inthe

title for

the

circuit 'board component location illustration,

and in

the

lookup

table for the schematic diagram and

corresponding component locator illustration.

The

Replaceable Electrical

Parts

list is arranged by assemblies

in numerical

sequence;

the components are listed

by

component number

(see

following illustration for

constructing

a

component number).

COMPONENT

NUMBER

EXAMPLE

I

Chmls-mwM

tornrmnems

have

no

kmbl!

Humw

pfeflx-act

end

d

kplatesble hlrical

Par!>

brl

The schematic diagram

and

circuit board component

location illustration

have

grids. A lookup table with the

grid coordinates is provided for

ease

of locating

the

component. Only

thecomponentsillustrated

on

thefaeing

diagram

are

listed in the lookup table.

When

more

than

one

schematic diagram is used to illustrate thecircuitry

on

a

circuit

board,

the circuit board illustration may only

appear opposite the first diagram

on

which

it

was

il-

lustrated; the

tookup

table will list the diagram number

of

other diagrams that the circuitry

of

the circuit

board

appears on.

R330

Oh-

H

-.--

--

1'

SYNC

GENERATOR

4

Modifid Component-See

Parts

List

(Depicted in grey.

or

with

grey

outline)

Plvg

to

E.C.

Board

Coaxial

connectore:

male

female

Plug

Index:

algnlfiss

uln

No.

1

Exlernal Screwdriver
Adiustmenl

Shiiding

Selected

value,

sea

Parts

LiM
DeeouplOd

or

Mltered

VO

tage

Refer

to

Dlsgrum

Number

-.

"L

Schematic

Name

--L

-

-

and Number

Table

8-1

REAR

INTERFACE

CONNECTOR

ASSIGNMENTS

DM505

SIMPLIFIED

BL

c"Ass:-l

GROUND

-

IED

BLOCK

DIAGRAM

Section

8-DM

505

I

LTS,

kR

d

STROBE

DC

n

CONVERTER

BCD

Dl

SPLAY

4

0

AC

CLOCK

FLOAT1

NG

25

VAC

SUPPLY

f15.75

V

138

+5

V

-12

v

Fig.

a-1.

Functions

Available

at

Rear

Connector

A

slot between pins 17 and 18

on

the

rear

connector

identifies the

DM

505

as

a

member

of

the digital mul-

timeter family. Insert a barrier in

the

corresponding

position

of

the power module

jack

to prevent other than

digital

muftimeter plug-ins from being

used

in that com-

partment, This protects the

plug-in

if specialized

connec-

tions

are

made

to

that

compartment. Consult the Building

a System

section

of

the

power

module manual

for

further

information.

High

and

Low

Input

(contacts

28B

and

28A)

Voltages

and

resistances can

be

applied dlrectly

through the rear interface circuit board contacts. Com-

parisons can be

made

between

front

panel

and

rear

interface measurement

sources

by

using

the

l

NPUT

EXT-

INT pushbutton located on the front panel.

Do

not

exceed

the

maximum

specified

input

voltage listed En the

Specifications section. Also

note that the accuracy is

derated

for

some

functions when applied at

the

rear

interface inputs.

This

information

is

also noted in the

Specifications section.

A/D

CONVERTER

BLOC

Af

BUFFER

-------

SWITCH

STATES

ARE

FOR

A

LOGIC

"0

'ONVERTER

fl

BLOCK

DIAGRAM

PARALLEL

BCD

OUTPUT

DIGIT

STROBES

m

01

02

03

w4

\

MULTl

PLEXER

-12

V

CLOCK

IN

AZ

LTER

C1103

0

CKT

SWITCH STATES

ARE

FOR

A

LOGIC

"0"

AT

U/D

AND

M/Z

INPUTS.

DE

VOLTS

I

CHECK

POWER

HJPPLIES

1

SELECT

200

mV

DC

RANGE.

DISPLAY

RESPOND

TO

CHANGES

iN

INPUT

VOLTAGE

Yes

1

SHC

7

CHECK

CLOCK

U1301,

U1303,

AMD

DISPLAY

CIRCUIT.

DISCONNECT

ONE

END

OF

R1424

TO

SEE

IF

U132f

OR

Cat421

OR

CR1422

LEAKAGE

IS

CAUSING

OFFSET.

1

3

DISCONMECT

CR1112

AUTO

ZERO

ClRCUlT

AMD

CR1113

-

Yes

BE

ZEROED

='

A

II

AND

CR1113

TO

SEE

IF

LEAKAGE

IS

CAUSING

Yes

OFFSET.

-

RECONNECT

R1424

AND

DISCONNECT

CR1421

AND

CR1422

Yes

-

REPLACE

GRIT12

REPLACE

CR1421

,

AND

CR1422.

REPLACE

U1321.

-

4AT

DM

lNPUT

APPEARS

AT

IT

(U12O1-15).

LOCK

U13Q1,

MD

DISPLAY

t

-

INPUT

1

V

DC

ON

2

V

DC

RAHGE.

I

CHECK

INPUT

SWITCH-

ING.

THERESHOULD

BE

NO

ATTENUATION OM

THE

2

V

RANGE.

i

>f

Yes

r

RESISTANCE?

CHECK

REFERENCE

ZENER

vttima;

GAIN

SETTING

RESlSTORS

1

I

R1111,

Rftl2,

R1212,

AND INTEGRATlON

CAP

1

~1101.

ALSO

CHECK

U1201

AND

DISPLAY

CIRCUIT.

a

CHECK DISPLAY ClRCUlT

IF

PART

OF

DISPLAY lNDlCATlON IS

MISSIHG, FIRST CHECK

THAT

DlSPLAY

BOARD

IS SEATED IN

ITS

SOCKET.

TO

DETERMINE

IF

THE

DISPLAY

INDICATES

THE

SAME

INFORMA-

TION

AS

THAT

COMING

FROM

U1303,

CHECK

THE

SIGNALS

FOR

EACH DIGIT,

ONE

DIGIT

AT

A

TIME.

FOR

EACH

DIGIT

OBSERVE

ON

AN

DURlNG THE

DIGIT

SELECT

PULSE,

ANY

ERROR

tNf

HAT

DIGITMUSTBE

CAUSED

BY

U1303.

PROBLEMS

WITH SINGLE DIGITS

CAN USUALLY

BE

TRACED

TO

THE

I

DISPLAY ITSELF, DISPLAY

BOARD

CON'NECTOR,

OR

DISPLAY

DRIVERS.

FOR

THE

MSD

ALSO

CHECK

01507.

1F

SlGW IS INCORRECT

CHECK

Ui303-5

AND

U1302E. IF

SIGN

IS

MISSING,

CHECK

DCV

AND

DC1

SWITCHES,

S2-8

and

S2-K,

PINS 1,2,

3.

FOR

DECIMAL

POINT PROBLEMS

CHECK

Q1406. SWITCHES

M-D,

S1-

H,

SI-A,

AND

S1-M-1,

2,

3.

4

CHECK

ACCURACY

OF

206

mV

DC

RANGE WITH APPROPRIATE INPUT.

.

IF

'DM

IS

OK

ON

2

V

RANGE

BUT

NOT

ON

200

mV RANGE,

CHECK

R1210,

R1211.

a1301

AND

SWITCHES

S2-M,

S2-D,

AND

Sf-B-1-2,s.

L

I

--

CHECK

ACCURACY

OF

REST

OF

DCV

RAMGES WITH APPROPRIATE

INPUTS.

IF

DM

FS

QKON

200

mVAND

2

V

RANGE

BUT NOT

ON

OTHER

RANGES, EITHER

THE

ATTENUA-

TOR NETWORK R1312

OR

THE

INPUT SWITCHING

IS

PROBABLY

DEFECTIVE.

IF

DTSPLAY

ON

20

V

RANGE IS

1/10

WHATITSHOULO

BE,

CHECK

SWITCHES

S2-B-4,5,6 AND

S1-J-1,2,

3.

DC

CURRENT

CHECK

POWER

SUPPLIES

K='

CHECK

DC

VOLTS

'=-+

CHECK

THAT

TEST

LEADS

ARE

CONHECTED

TO

LOW

AND

mA

FUSE

F1521

CHECK

FOR

A

DC

VOLTAGE

AT

ADC

INPUT

(U3201-15)

THAT

CORRESPONDS

TO

EXPECT

ED

'READING.

FULL

SCALE

INPUT

CURRENT

ON

AMY

DC

CURREMT

RANGE

SHOULD

PRODUCE

200

mV

DC

ATY1201-15.

I

VOLTAGE

AT

W1201-15

CORRECT

S2X4,

5,

6

rnwrCnL

i

CONVERTED

DC

CHECK

SWITCHES

VOLTAGE

(0.2

V

F.S.)

BETWEEN

CURRENT

PRESENT

AT

INTlFm

<

SHUNTS

AND ADC

SWITCH

S3-,

I

CHECK

CURRENT

SHUMTS

R1425,

R1426,

AND

R1521.

CHECK

INPUT SWITCHING

FDR

THE

SHUNTS.

ALSO

CHECK

PROTECT10N

BRIDGE DIODES

CR1621.

flg.

8-6.

OHMS

CHECK

POWER

SUPPLIES

G

I

CHECK

DC

VOLTS

I

REPLACE

LAMP

DS1410.

ALSO

CHECK

CR1301

AND CR1302

FOR

GOOD?

LEAKAGE. THEY

MAY

HAVE

BEEN

DAMAGED

WHEN

LAMP

WAS

y

u

INPUT

SHORTED

IS

DISPLAY

E-i,

2,

3

ZERO

w

Yes

71

CONNECT A KNOWN

RESISTOR

TO

DM

INPUT

WHICH

IS

CLOSE

IN

VALUE

TO

FULL

SCALE.

MEASURE

VOLTAGE

FROM

VOLTSIR

TO

LO

INPUT.

FOR

FULL

SCALE

READING.

VOLTAGE

ACROSS

RESISTOR

BEING

MEASURED

SHOULD

BE

0.2 v FOR

200

n

RANGE;

0.2

v

FOR

LO

L-2

AND

REST

OF

RANGES

AND 2 V

FOR

HI

R

AND

REST

OF

RANGES.

NOTE

THAT

RESISTANCE

MEASURED

BY

DM

505

WlLL

BE

PARALLEL

COMBINAT

ION

OF

RESISTOR

AND

TEST

M'ETER

RESISTANCE.

t

CHECK

PATH

FROM

VOLTS/fi

INPUT

TO

ADC

INPUT

(U1201-15).

VOLTAGE

AT

THESE

POlNTS

SHOULD

BE

EQUAL.

WMEM

MEASURING

VOLTAGE

AT

U1201-15

THE

MEASUREMENT

DEVICE

READfNG

WlLL

BE

THE

UNLOADED

VOLTAGE

MULTIPLIED

..arr,

WHERE

Am

IS

MEASUREMENT

DEVICE

RESISTANCE.

MEASURE

VOLTAGE

FROM

U1311-2

TO

U1311-6.

IT

SHOULD

BE

10 V ON

200

fi

RANGE;

lOV

FOR

MIR

AND

REST

OF

RANGES;

AND

1

VFOR

PO

n

ANDREST

OF

RANGES.

CHECK

CURRENT

SOURCE

Q1311

AND

ASSOMATED

COMPO-

NENTS.

IF

THESE

ARE

OK,

CHECK

R1304,

R1413,

R1305.

ALSO

CHECK

U1311.

/

VOLTAGES

AT

U1311-2

AND

CHECK

OP

AMP

W311

AND

PROTECTION

DIODES

CRt301

AND

CR1302.

Fig

&7.

CHECK

kR

SWITCt

S2-F-1,2,3 ANQS2-F*

6;

ATTEFFUAT

SWLTCHES;

PRO71

TlON

DIODES

CR1

AND

CR1302;

Rlr

AND

W317.

CHECK

LO

n

SWITCH

$2-H-1 , 2,

3;

200

R

SWITCH

S1-GI,

2,

3;

AND

RESISTORS R1413

AND

R1305.

HECK

R1304.

1

!-F-l,2,

3

AMDS2-F-45,

ATTENUATOR

WITCHES;

PROf

EC-

ON

DIODES

CR1301

VD

CR1302;

Rf412;

HD

U1311,

AC

VOLTS

CHECK

POWER

SUPPUES,

MISCELLANEOUS NOTES

INABILITY

TO

ZERO

MAY

BE

CAUSED BY

LEAKY

U1211

IMWTS

OR

LEAKY

~1215.

IF

zEao

CAN

BE

SETON

200

mVAMD2 YRANGEBYT

ISOFFON20 VRANGEC1021(

86

1

MAY

BE

WRONG VALUE.

0

AN

ABNORMALLY

LOW

DISPLAY

IEEDICATTON

AT

20

kHz

OM

200

mV

AND 2 V

RANGE

CAN

BE

CAUSED

BY

U12f

l

BEING

DEFECTIVE.

AMPLITUDE

NONLINEARITY CAN

BE

CA~SED

BY

LEAKY

FEEDBACK

DIODES

CR1221

AND

CR1222.

WlTH

AC

VOLTAGE

AT

INPUT,

CHECK

FORADCVOLTAGEATAC

CONVERTER

OUTPUT.

ACROSS

~1221,

WHICH

CORRES~UDS~TO

THE

INPUT

VOLTAGE. FULL SCALE

INPUT

SHOULD

PRODUCE

2

V

DC

ACROSS

C1221

ON

ANY

ACV

RANGE. MEASUREMENT DEVICE

READING

WILL BE SLIGHTLY

LOWER

THAN EXPECTED

BECAUSE

OF

ITS LOADING

EFFECT.

VOLTAGE

ACROSS 61221

CORRECT

S2-C-4,s

CHECK

AC

VOLTAGE

AT

U1321-6.

AMPLlTUWE WlTH

FULL

SCALE

lfitPUT

SHOULD

BE

200

mV

ON

200

mV

AND

20

V

RANGES,

2

V

ON

2

V

AND

200 V RANGES

AND

500

mV

ON

500

Y

RANGE-VOLTAGEWILLBE

SLIGHTLY LESS BECAUSE

OF

NORMAL LOSSES BEFORE U132t.

t

I

CHECK

AC

CONVERTER

U1211

AND

ASSOCIATED

COMPONEMTS, IF

AT

U1321-6

SOME

RANGES

WORK

AND

OTHERS

CORRECT

DON'T,

CHECK

GA1N

SETTrNG

RESISTORS

AND

SWITCHES

BETWEEN U1321-6

AND

U1211-2.

I

CHECK

GAIN

OF

U1321.

AC

VOLTAGE

AT

U1321-3

AND

U1321-6

SHOULD

BE

EQUAL.

NOTE

THAT

I

MEASUREMENT

DEVICE

MAY

I

DECREASE

THE

YOLTAGE

AT

U1321-3

DUE

TO

CAPACITANCE

AND

RESISTANCE 50

THE

TWO

MEASUREMENTS SHOULD BE
MADE

$1

MULTANEOUSLY.

NO

L11321

EQUAL

ASSOCIATED

COMPONENTS

-

CHECK

INPUT

SWlTCHING

AND

ATf ENUATOR

COMPENSATION

CAPS

C1312, C1313,

AND

C1311.

WHEN

MAKING

MEASUREMENTS

AT

THE

ATTENUATOR

BE

AWARE

OF

THE

LOADING

EFFECT

OF

CAPACITANCE AMD RESISTANCE

OF

THE

MEASUREMENT DEVICE.

STEP

1

I-15.75

V

R1021

ADJUSTMENT

LOCATIONS

STEP

6

r

LOCATIONS

STEP

6

HI

R

. STEP?

I

LO

n

R1413

1

CLKTP

1

STEP

10

I

-2

Y

AC

Sf

EP

11

R1323

10

kHz

MAlN

BOARD

(A10

ASSY)

C13f

3

(Adjustment

made

from

back

of

circuit

board.)

POWER

SUPPLIES

FOR

ANY

MALFUNCTION

WHEH

THE

CAUSE

IS

NOT

READILY

APPARENT,

FIRST

SUPPLIES.

f

12

V

SUPPLY

NO

ALSO

CHECK

FOR

EXCESSIVE

+5

Y SUPPLY

LOAD

ON

f 5 V

SUPPLY.

13A

AND

138

CHECK

FOR

MALFUNCTION

IN

-12 Y SUPPLY

WHICH

MAY

1

LOAD

DOWN

THE

/

TRANSFORMER.

I

ALL

SgEPLIES

I

FOR

ANY

MALFUNCTION

WHEN

THE

CAUSE

IS

NOT

READlLY

APPARENT,

FIRST

SUPPLIES.

No

+12

v

SUPPLY

;

FOR

EXCESSIVE

+5

V

SUPPLY

v

SUPPLY.

Yes

22.

ALSO

FUNCTION

rHlCH

MAY

IS

THERE

CHECK

MAINFRAME

CHECK

TRANSFORMER

T1001,

CRlOlt. C1011,

AND

REGULATOR

U1021.

CHECK

FOR

EXCESSlVE

LOAD

ON

+12 Y SUPPLY

BY

DlSPLAT

CIRCUIT.

ALSO

CHECK

FOR

MALFUNCTION

IN

t15.75

V

AND -12

V

SUPPLIES

WHICH

MAY

LOAD

DOWN

THE

TRANSFORMER.

ALL

SUPPLIES

&

-12 v SUPPLY

NO

IS

THERE

R'

MAlMFnmE

1

Yes

CHECK

TRANSFORMER

T1001,

CR1111, C1111,

AND

REGULATOR U1121.

ALSO

CHECK

FOR

EXCESSIVE

CHECK

POWER

SUPPLIES

AC

CURRENT

'7

CHECK

DC

VOLTS

'-4

CHECK

AC

VOLTS

Q

I

CHECK

DC

CURRENT

I

NOTE:

THE

DM

505

AC

CURRENT

READING

WILL

BE

SLIGHTLY

HIGHER

(4

TO 6 COUNTS)

FOR

FULL

SCALE

AT

HIGHER

FREQUENCIES

(1

k

TO

10

kHx).

THIS

tS

DUE

TO

VERY

LOW

SOURCE

IMPEDANCE

OF

CURRENT

SHUNTS,

WHICH IS

NOT

AFFECTED

BY

STRAY

CAPACi-

TANCE

TO

THE

SAME

EXTENT

AS

AC

VOLTAGES

FROM

THE

ATTEN-

UATOR NETWORK.

SZ-L-3

CORRECT

S2-k-1,

2,

3

CHECK

CURRENT

SHUNTS

R1425,

R1426,

AND

R1521

PARTS

LOCATION

GRID

Fig.

8-10.

Main

Board

(AlO).

ATION

GRID

11n

Board

(AtO).

COMPOMENT

HUMBER

MJlHPLE

Component

Number

Table

8-2

COMPONENT

REFERENCE CHART

i

+I

ZV

UNREG

I

-

P+SV

UMREC

NOTES

:

*

TOP

Vf

w

EW

+sv

1

S1

208rnV

52

OCV

INPUT

CONDITIDNINC

@

mae-21

MAIN

BOARD

Static

Sensitive

Devicts

See

Ma-

Shn

COMPONENT

MUYlBER

EXAMPLE

hwnenf

Nu&

V

.

--

I

C7aslsWUnM

ahmp~nemk

have

nr

AaJembly

thmh

~ehx-see

ewd

ol

Redma&

Uedncal

Pak

hd

PARTS

LOCATION

GRID

Fig.

811.

Display

Board

(All).

Static Sensitive

Devices

See

Maintenance

&lion

COMPOHEllT

NUMBER

€%AMPLE

ComNnenf

number

-

I

A=W

J

I.

t

hut

Number

(d

und)

UlrarmpumM

mwnemk

no

Wmbly

Hunter

pel~x-e

end

ol

Replaceable Oenrlul

Pafa

LsI

Table

8-3

COMPONENT

REFERENCE

CHART

I

I

I

I

I I

A/D

CONVERTER

-@----

PARTIAL

AC CONVERTER

R1221

R1222

+12v-+12v

+sV

-

+5V

TR

1

GGER

LO

-

-12v-

-12v

CLOCK

FREQ

ADJ

@

26Q2-22

DM505

!DISPLAY

DRIVERS

1

Static

Sensitive

Devices

See

Maintenance

Section

COMPONEMT

NUMBER

EXAMPLE

Component

Number

I

Number

Subassemb!~

N~~M

Number

(11

medl

Cnass

rmunled

comwnems

hdw

m

Awmb

y

Nrmper

pref

x-tee

end

01

Replaceable

E

eclr

cal

Pact

L~sr.

MAIN

BOARD

@

,,

REPLACEABLE

MECHANICAL

PARTS

PARTS

ORDERING

IMFORMATION

INDENTATION

SYSTEM

This

mechanical

parts

list

is

indented

to

indlcate

item

Replacement

parts

are available from

or

through your local

relationships. Following

is

an

example

of

the

indentation

system

Tektronix, Inc.

Field

Office

or

representative.

used

in

the

description column.

Changes

to

Tektronix instruments

are

sometimes made to

accommodate improved components

as

they become available,

and to give you the benefit of the latest circuit improvements

developed in

our

engineering department. It 1s therefore

important,

when

ordering

parts,

to

include

the

following

information in your order:

Part

number, instrument

type

or

number, serial number, and modification number

if

applicable.

If

a

part

you

have

ordered

has

been replaced with

a

new

or

improved

part,

your local Tektronix, Inc.

Field

Office

or

representative will

contact

you

concerning

any

change

in

part

number.

12345

Name

Description

Assembly

andlor

Component

Attaching

parts

for

Assembly

and/or

Component

---

-+-

Detail

Part

of

Assembly

andlor

Component

Attaching

parts

for

Detail

Part

---

-+-

Paris

of

Detail

Part

Attaching

parts

for

Parts

of

Detail

Part

,.--

=+*-

Change information, if

any,

is

located at the

rear

of

this

Attaching

Parts

always

appear In

the

same indentation

as

manual.

the

item a mounts, while

the

detail

parts

are

indented to

the

right.

Indented items

are

part

of,

and

included with,

the

next

higher

SPECIAL

NOTES

AND

SYMBOLS

indentation.

The

separation

symbol

-- - --

-

Indicates the

endof

attaching parts.

XOOO

Part

first

added

at

this serial number

OOX

Part

removed

after

this serial

number

FIGURE

AND

INDEX

NUMBERS

Items

in

th~s

section

are

referenced by fiqure

and

index

.

-

numbers to

the

illustrations.

n

ACTR
ADPTR
ALlGN

AL

ASSEM
ASSY
AnEN

AWG

80

BRKT

BRS

BRZ

BSHG

CAB
CAP

CER

cnAs

CKT

COMP

CONN

cov

CPCG

CRT

OEG

OWA

lNCH

NUMBER

SIZE

ACTUATOR

ADAmER

ALIGNMENT
ALUMINUM
ASSEMBLED
ASS€ MBLY
ATTENUATOR
AMEFtlCAN WlRE GAGE
BOARD

BRACKET

ERASS

BRONZE
BUSHING
CABINET
CAPACITOR
CERAMIC
CHASSIS
CIRCUIT

COMPOSTTION

CONNECTOR

COVER

COUPLING
CATHODE RAY

TUBE
DEGREE
DRAWEA

ELCTRN
ELEC
ECCTLT
ELEM

EPL

EQPT
EXT
FIL
FLEX

FLU

F

LTA

FR
FSTNR

FT

FXD

GSKT

HDL

HEX
HEX

HD

HEX

SOC

HLCPS
HLEXX

HV

IC
ID
IDEMT
IMPLR

Amchlng

pa*

must

be

purchased

separately,

unless

otherwh

specllkd.

ITEM

NAME

In the

Parts

List,

an

ltem

Name

is

separated

from

the

description by

a

colon

I:).

Because

of

space

limitations,

an

ltem

Name

may sometimes

appear

as

incomplete. For further ltem

Name

identification,

the

U.S.

Federal Cataloging

Handbook

H6-I

can

be

utilizd where

possible.

ABBREVIATIONS

ELECTRON
ELECTRICAL
ELECTROLYTIC
ELEME

Wr

ELECTR:CAL PARTS LIST
EQUIPMENT
EXTERN4L
FlLLlSTER

HEAD

FLEXlBLE
FLAT

HEAD

FILTER
FRAME

or

FRONT

FASTENEA

FOOT

FIXED
GASKET
HANDLE
HEXAGON
HEXAGONAL

HEAD

HEXAGONAL

SOCKET

HELICAL COMPRESSION
HELICAL EXTENSION

HIGH

VOLTAGE

INTEGRATED

ClRCUlT
INSIDE DIAMETER
lOENFlFlCATlON
IMPELLER

IN

lNCH
INCAND lMtAt4DESCENT
tNSUL IMSULATOR
INTL INTERNAL
LPHLDR LAMPHOLOER
MACH

MACHINE

MECH

MECHANICAL

MTG

MOUMTING

NIP

NIPPLE

NON

WlRE NOT WlRE

WWND

OBD

ORDER

BY

IJWCRlPTlON

OD

OUTSIDE DIAMETER

OVH

OVALHEAD

PH

BRZ

PHOSPHOR BRONZE

Pi

PLAlM

or

PLATE

PLSTC

PLASTIC

PN

PART

NUMBER

PNH

PAN

HEAD

PWU

POWER

RCPT

RECWTACLE

RES

RESISTOR

RGD

RIGID
RLF RELIEF
RTNR RETAlNER

SCH

SOCKETHEAD

SCOPE

OSCtLLOGCOPE

SCR

SCREW

SE

SINGLE

END

SECT

SECTION

SEMICOND SEMICOMOUCTOR
SHLO SHIELD
SHLDR SHOULDERED

SKT

SOCKET

SL SLIM

SLFCKG SELFIOCKING

SLVG SLEWING

SPR

SPRING
SQUARE

SQ

SST STAINLESS STEEL

STL

ST

EEL

SW

SWITCH

T

TUBE

TERM TERMINAL

THO

THREAD

THK THICK

TNSN TENSION

TPG

TAPPING

TFlH

TRUSS

HEAD

V

VOLTAGE

VAR VARIABLE

WI

WITH

WSHR

WASHER

XFMR

TRANSFORMER

XSTR

TRANSISTOR

Replaceable

Mechanical

Parts-DM

5115

CROSS

INDEX-MFR.

CODE

NUMBER

TO MANUFACTURER

Mfr.

Code

Manufacturer

Address

City,

State,

Zip

OOOBli

FAB-TEK

17

SUGAR

HALLOW

ROAD DANBURY.

CT

06810

Am,

IHC.

BERG

BlECTROF1ICS,

WC.

HEW

WG.

CO.

CENTIlALda

ELECTROUICS,

DIV.

OF

GLOBE-WNXOH,

INC

.

PISCHER

SPECIAL

MFG.

GO.

TEXAS

TISTRUHENTS,

mC.,

METALLURGICAL

MATERIALS

DIV.

ILLINOIS

TQOL

WORKS,

fWC.

SNAKEPROOF

DIVISIOM

TEKTROHIX

,

INC

.

TEXAS

IMSTRUPIENTS,

me.,

CONTROL

PRODUCTS

D

IV

.

CENTRAL

SCREW

CO.

SEASTROM

PIFG.

COHPAHT,

IEIC.

N.

I..

TNDUSTRIES

,

ENC.

,

SOUTHERN

SCREW

DIV.

CAHCAR

SCREW

AND

MG.

CO.

P

0

BOX

3608

YOUK

EXPRESSWAY

147

W.

MICHIGAN

AVE.

P

0

BOX

858

446

MORGAN

ST.

34

FOREST

STREET

ST.

CHARLES

ROAD

P

0

BOX

500

34

WREST

ST.

2530

CRESCENT

DR.

701

SOMOKA

AVENUE

P.

0.

BOX

1360

600

18TR

AVE.

HABRISBWRG,

PA

17105

NEW

CU?BEIILIWD,

PA

17070

KENILWORTH,

NJ

07033

FORT

DODGE,

IA

50501

CIACIIWATT.,

OH

45206

ATTLEBORO

,

HA

02

703

BROADVIEW,

IL

60153

GLENDALE.

CA

91201

STATESVILLE,

HC

28677

ROCKFORD,

IL

61101

REV

A.

OCT

1979

Replaceable

Mechanical

Parts--DM

505

Fig.

&

Index

No.

Tektronix

Part

No.

Seriallhlodel

No.

Eff

Dscont

Mfr

Code

Qtv

12345

Name

8

Descriation

Mfr

Part

Number

2

SHIELD,ELEC:

SIDE

1

MARKER,

1DEWT:MARKED

DM505

MULTIWTER

1

LRNS,LED

DSPL:RED

10

PUSH

BUTTON:GRAY

2

PUSH

BUTT0N:CBARCOAL

GRAY

1

JACK.TEP:BLUE

(ATTACHING

PARTS)

1

NUT,PLAXN,HEX.:0.25-32

X

0.375

IHCH

BUS

I

TERMINAL,LUG:0.25

INCH

DIA,SE

1

WASHER,FLAT:0.256

ID

X

0.438 INCU

OD,BRS

---*---

1

JACK,TIP:BLACR

1

JACK,

TIP

:

BLACK

(ATTACHING

PAWS)

1

WT,PLAXN,HEX.:0.25-52 X 0.375 INCH

BUS

1

TERMINAL,WG:0.25

INCH

DIA,SE

I

WASHER,FLAT:0.256

ID

X

0.438

INCH

OD,BRS

---*---

1

JACK,TIP:AED

1

JACK,TIP:RED

(ATTACHING

PARTS)

1 NUT,PMIN,HEX.:0.25-32

X

0.375

INCH

BRS

1

TeRMfNAL,GUG:0.25 INCH

DIA,SE

1

WASHER,FLAT:0.256

ID

X

0.438 INCH OD,BRS

---*---

1

NUT,PLAXN,RNUUL:0.25-28

X

0.25

INCH

L,BRS

I

STUD,SHOULDERED:6-32

X

0.40

INCH

tONG

1

KNO6,LATCR:

I

LATCH,RETAZNXUG:PLUG-XH

(ATTACHING

PARTS)

I

SCR,TPG,THD

FOR:2-32

X

0.312

fNCfl,PNH

STL

---*---

1

BAR,

LATCH RLSE

:

1

PANEL,FRONT:

(AITACHIAG

PARTS)

1

SCREW,MACHXNE:6-32

X

0.375

fNCH,TRH

STt

---*-*-

1

SUBPANEL,FRONT:

(A~ACHIW

PARTS)

2

SCR,TPG,THIl FOR:6-32

X

0.50

IWCH,PNH

STL

2

SCMW,TPG,TF:6-32 X 0.375,TAPTITE,PMH

---*---

1

CKT

BOARD

ASSY:DISFLAY(SEE All

EPL)

1 . TERM.

SET,PfN:36/0.025

SQ

PIW,ON

0.1

CTRS

1.

.

TERPI.

SET,PIN:l

X

36,O.l

CTR,O.9

L

2

SHIELD,ELEC:CIRCUIT

BOARD

(AITACHING

PARTS

1

SCREW,MACHINE:4-40

X

D.tB8

TMCB,PNH

STL

---*---

2

BRACKET,

SHIELD : POLYCARBONATF

6

EXTENSION

SHAPT:2.764 L

X

0.187

00

1

CUT

BOARD

ASSY:MAIN(SEE A113

EPL)

(ATTACHING

PARTS)

4

SCR,TPG,THD

POR:6-20

X

0.313

fNCH,PNH

STL

- - - * -

-,

-

.

CUT BOARD

ASSY

INCLIIDES:

1

.

HEATSINK,XSTR:AL W/0 TABS

1

.

SPAC&R,POST:O.

188"

HEX

1.627''

L,AL

2 . SOCKET,PLUG-IN:16

COMTACT,LOU

CLEARANCF:

1

.

SOCKET

,PLUG f N:MICROCIRCUfT,

8

CONTACT

1

.

CAPACfTOR:(SEE

A10C1313 EPL)

4

.

CLIP,ELECTRtCAL:FOR

0.25

INCH

DIA FUSE

2

.

BUTTON,PLUG:0.25

HTG

HOLEDIA,NYLON

1

.

SHIELD, ELEC:AC COMVERTER

1

,

SWTTCH,PUSM:(SEE

A10S2

EPL)

3095-402

A313-136

OBD

3095-402

A313-136

OBD

OBD

OBD

OED

OBD

OBD

OOOBH

80009
82647

7

3803

REV

A,

OCT

1979

Replaceable

Mechanical

Parts--DM

505

Fig.

&

Index

Tektronix

SeriallModel

No.

Mfr

No.

Part

No.

Eff

Dscont

Qty

1

2

3

4

5

Name

&

Description

Code

Mfr

Part

Number

.

SPACER,FB

SW:

BROWN,

0.275

KMCH

LONG

.

SHfTCH,PUSH(SEE

AlOSl

EPt)

.

SFIIITCI~,PUSH:(SEE

~10~3

EPL~

.

S?ACER,PUSH

SW:0.13

W

X

0.375

INCH

L,FLSTC

.

SDCKET,PLUG-IN:8

PIN,FEMALE

.

TERM,TKST

P0INT:BRS

CD

PL

.

NUT,SLEEVE:4-40

X

n.188 X 0.50"

LONG

.

WASHEU,l.OCK:84

fNTL,O.O15THK,STL

CD

PL

WIRE

SET

,ELKC:

FR

SECT,

PLUG-I

H

:

BOTTOM

FR

SECT,PLUG-1N:BOTTOH

SUPPORT,

PLUG

f

N:

WASHER,FGAT:O.I41

ID

X

0.04

THK,AL

SPBtNG

,GROUND:

FLAT

FR

SECT,PLUG-IN:TOP

REV

A,

OCT

1979

Fig.

&

Index

Tektronix

SeriallModel

No.

Mfr

No.

Part

No.

Eff

Dscont

Qty

1

2

3

4

5

Name

&

Description

Code

Mfr

Part

Number

MANUAL

CHANGE INFORMATION

At

fektronix,

we

continully

&river

to

keep

up

with

the

latest

dmtronic

devehprnents

by

adding

circuit

and

~ornponent

irnpmvements

to

our

instruments

as

smn

as

thy

are

dwulopd

and

tested.

Ssmetimes,

due

to

printing

and

shipping

requirements,

WB

can't

get

these

changes

immediately

into

printed

manuale.

Hence,

your

manual

may

cmniak?

new

change

information

on

the

following

pages.

A

single

change

may

affect

several

sections.

Since

the

change

information

sheets

am

carried

in

the

manual

until

all

changes

are

prrnanently

antered,

some

duplication

my

aceur.

If

no

suuh

change

pagas

tappar

following

this

page,

your

manual

is

corm3

as

printed.

SERVICE

MOTE

Becausm

of

the

universal

parts

procurement

problem, -me electrical

parts

in

your

instrument

may

be

different

from

tha

dgscrihd in

the

Replaceable

Electrical

k-ts

List.

The

parts

used

will

in

no

way

alter

or

compromise

the

performance

or

mliability

of

thii

instrument.

They

are

Installed

when

necessary

to

ensure

prnrnpt

delivery

to

the

customer.

Qrdlw

mplawrnent

parts

from

the

Replaceable

El&al

Parts

List.

-

m

-

-

L.

*-bn

.r

CALlBRATlON

TEST

EQUIPMENT

REPLACEMENT

CatlbrMon

Ted

Equipment

Chad

-

This

6.R

cornparer

TM

500

proU

perf-in&

f&

hhi

k

daw

?&LM%$

equ~pfTi&:

Only

tho-

eharacteristlcei

where

significant

spec14Kiation

differences

occur,

am

listed.

In

ssms

mms

the

new

imrurnent

may

not

be

a

total

functional

raplament.

Additlond

suppM

inktrurnentation

may

Be

needed

or a chan*

in

calibration

procedure

may k necessary.

DM

501

repl~e~7[319

PG

501

raptaces

107

P'G

501

-

Rlsrrtlmr

1-8

than

107

-

Rislirnr

ks

than

J-Cu

-7

-

f

I

3,6

ns

into

50

n.

3.0

ns

into

50

R,

1

108

$G

a1

-

5 v output pulss;

108

-

10

\I

output

pulse

Sd

n~

RiWm

1

ns

Rlmtlrne

---

-.

5

-

PG

502

rwlaces

107

-

*.

-

--

- --

-A

-

1M

W

502-5V

output

108

-

10

V

autiut

111

PG

502

-

Rwirno

Iws

than

11

1

-

Rlwlme

0.6

ms:

3t3

t

ns;

IQ

ns

I(

to

250

M

Pretrigger

pulw

Prertlg~per

pulse

I

Performance

of

placement

equiprnmt

is

the

same

or

115

Mter

than

equipment

bdng replaced.

PG

506

-el

tiva-gol

qj

106

-

Pasltlve

and

Negatiw

frlugQr

output

sig-

going

triggar

output

n&

rwt

leaqt 1 V;

signal,

50

m

and

1

V;

High

Amplitude

out-

High

Amplituth

output,

put,

m

v.

100

v.

BG

Xt&

-

Dm

nd

have

.

0502-01

-

Camparator

output

chapped

feature.

can

be

alwnately

chopm

to a

refer-

etlce

voltago.

SG

603

-

Amplitude

ran*

5

mV

to

9.5

V

p-p.

l#B

-

AmplItti#~ range

40

mV

to

tov

p-p.

SG

603

-

Frequency range

a50

kHz

to

~FQ

MHz

TG

a1

-

Trigger

outprrt-

slaved

to

marker

output

from

5

SEC

thtough

100

ns.

One

time-mark

can

b

gerneratd

at

a

timw

0532-01

-

Fmque~ay

range

&5MHata5OOt#z.

SG

504

-

Frequerrcy range

24.5

MHz

to

IDSO

MHz.

TG

31

-

Rlgm

CutpiA*

duve~

te

markel

output

from

5

mc

through

100

ns.

Om

ttmmztrirk

mn

bo

mated

at

a

time.

TG

501

-

Trigger

output-

slaved

to

masker

output

fmm

5

thrwgh

1M)

ns,

One

time-mark

can

be

-retest

at

0532-01-

Frquency

ran-

65

MH2

to

500

MHz.

IlOA

-

Trigw

pulses

1,14

100

Hz;

1,10.

and

100

kHz.

Multiple

timemarks

an

he

**rate4

sirnultaw

eeusl

y

.

181

-

Multlple

tlinE-rtlark~

184 - Sapwata

triww

pulses

at

1

atnd

0.1

I=

10,

1,

md

0.1

Ins;

10

ad 1 #.

-1 - Separate

triggw

pui-,

from

5

%ec:

to

0.1

pa.

Multipre

timgmarb

can

be

gnertrtsd

dmultan-

mdy.

1

a

time.

I

NQTE:

All

TM

LW

gemrdor

rutplss

are

m-pr&.

All

TM

5W

plug&

instruments

rmqulrr

TM

WKtSaStes

Powr

Medcde.

REV

8,

JUN

1Q78

Change

Reference:

TEXT

CORRECTIONS

Step

5.

parts

d.

and

e.

CHANGE

TO

READ:

d.

Set

the

ac

calibrator

for

0.224

Vac

ms

at

50

Hz

50.2

Hz

or

60

Hz

?0.2

Hz.

e.

CHECK--that

the

maximum

display

reading

is

51.0.