Hameg HM 203-7 Manual de usuario

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Instruments

MANUAL

Oscilloscope

HM

203-7

Table

of

contents

Oscilloscope

datasheet

with

technical

details

.

P

1

Accessories

.Z

1

Operating

Instructions

General

Information

.Ml

Use

of

tilt

handle.

Ml

Safety.Ml

Operating

conditions.M2

Guarantee

.M2

Maintenance.M2

Switching

over

the

mains/line

voltage.M2

Type

of

the

signal

voltage

.M3

Amplitude

Measurement.M3

Time

Measurements.M

4

Connection

of

Test

Signal

.M

6

First

Time

Operation.M

7

Trace

Rotation.

M

7

Probe

compensation

and

use.

M

7

1

kHz

compensation.M

8

1

MHz

compensation.M

8

Operating

modes

of

the

vertical

amplifiers

....

M

8

X-Y

Operation.

M

9

Phase

difference

measurement

in

DUAL

mode

.

M

9

Measurement

of

an

amplitude

modulation

....

M10

Triggering

and

time

base.M10

Automatic

Triggering.M10

Normal

Triggering,

Slope.Mil

Trigger

coupling.

Mil

Alternate

Triggering.Ml

2

Line

Triggering.Ml

2

Triggering

of

video

signals.Ml

2

External

triggering,

Trigger

indicator.Ml3

Holdoff-time

adjustment.Ml

3

Component

Tester.Ml

3

Test

patterns.Ml

6

Short

instruction

K

1

Front

panel

elements

Folder

with

front

view

.K

2

Test

Instructions

General.T

1

Cathode-Ray

Tube;

Brightness

and

Focus,

Linearity,

Raster

Distortions.T

1

Astigmatism

Check.T

1

Symmetry

and

Drift

of

the

Vertical

Amplifier

.

.

.

.

T

1

Calibration

of

the

Vertical

Amplifier.T

1

Transmission

Performance

(Vertical

Amplifier)

.

.

.

T

2

Operating

Modes:

CH

I/ll,

DUAL,

ADD,

CHOP.,

INVERT

and

X-Y

Operation.T

2

Triggering

Checks

.T

3

Timebase.T

3

Holdofftime

.T

4

Component

Tester.T

4

Trace

Alignment.T

4

Mains/Line

Voltage

Checks.T

4

Oscilloscope

HM

203-7

Service

Instructions

General.SI

Instrument

Case

Removal.SI

Operating

Voltages.SI

Maximum

and

Minimum

Brightness.SI

Astigmatism

control.S

2

Trigger

Threshold.S

2

Trouble-Shooting

the

Instrument.S

2

Replacement

of

Components

and

Parts.S3

Replacementof

the

Power

Transformer.S3

Adjustments.S3

Circuit

Diagrams

Wiring

Diagram.D

1

Identification

of

electrical

components.D

2

Y-Inputs,

Attenuators,

Preamplifier

Channel

I

and

Channel

II.D

3

Y

Intermediate

Amplifier

Channel

I

and

Channel

II

Channel

Selection,

Component

Tester.D

4

Trigger

Circuit,

TV

Sync

Separator,

Calibrator.

.

.

.D

5

X

and

Y

Final

Amplifier.D6

Timebase

Circuit,

Trigger

Control.D

7

CRT

Circuit,

Unblanking

.D

8

Power

Supply.D

9

Component

Locations

EY

Board.DIO

Component

Locations

CO

(IF)

Board.DIO

Component

LocationsXY

Board.Dll

Component

Locations

TB

Board.D12

Subject

to

change

without

notice

5.91

•

203-7

OSCILLOSCOPE

HM

203-7

Specification

(

21

°

C;

ismin.)

Vertical

Deflection

Operating

modes;

Channel

I

orCh.

II

separate,

Channel

I

and

II:

alternate

or

chopped;

(Chopper

frequency

approx.

0.4

MHz).

Sum

or

difference

of

Ch.

I

and

Ch.

II.

(channel

II

invertible).

X-Y

Mode:

via

Channel

I

and

Channel

II.

Frequency

range:

2x

DC

to

20MH2

(-3dB).

Risetime:

approx.

17.5ns.

Overshoot:

^1

%.

Deflection

coefficients:

10

calibrated

steps

from

5mV/div.

to

5V/div

in

1-2-5

sequence.

Accuracy

in

calibrated

position:

±3%.

Variable

2.5:1

to

max,

12.5V/div.

Y-magnification

x5

(calibrated)

to

1

mV/div.

±5%

(frequency

range

DC

to

3.5MHz,

—3dB)

Input

impedance:

1

MQ

II

25pF.

Input

coupling:

DC-AC-GD

(Ground)

Input

voltage:

max.

400V

(DC

+

peak

AC).

Y-output

from

Ch.

I

or

Ch.

II

(optional)

Trigger

System

With

automatic;

10Hz-40MHz.

>0.5div.

normal

with

level

control

from

DC-40MHz.

Slope:

positive

or

negative.

ALT.

triggering

;

LED

indication

for

trigger

action.

Sources:

Ch.

I,

Ch.

II,

line,

external.

Coupling:

AC

(S10Hz

-10

MHz),

DC

(0

-10

MHz),

LF

(0

-

<50kHz),

HF

(>1,5kHz

•

40MHz).

Threshold

external

>0.3V.

Active

TV-Sync-Separator

for

line

and

frame.

Horizontal

Deflection

Time

coefficients:

18

calibrated

steps

from

0.2|is/div.

to

0.1

s/div.

in

1-2-5

sequence,

accuracy

in

calibrated

position:

±3%.

variable

2.5:1

to

max.

0.25s/div.,

with

X-Magnifier

x10

(±

5%)

to

==

20ns/div..

Hold-Off

time:

variable

to

approx.

10:1.

Bandwidth

X-Amplifier:

DC-3

MHz

(-3dB).

Input

X-Amplifier

via

Channel

II,

sensitivity

see

Ch.

II

specification.

X-Y

phase

shift:

<3°

below

220kHz.

Z

input

(optional)

Component

Tester

Test

voltage:

approx.

8.5Vm,5

(open

circuit).

Test

current:

approx.

8mA,(shorted).

Test

frequency:

^

line

frequency.

Test

connection:

2

banana

jacks

4mm

0.

One

test

lead

is

grounded

(Safety

Earth).

General

Information

Cathode-ray

tube:

D14-364

P43/123,

or

ER151

-GH/-,

rectangular

screen,

intern,

graticule.

8x10cm

Acceleration

voltage:

2000V,

Trace

rotation:

adjustable

on

front

panel.

Calibrator:

square-wave

generator

==

1

kHz

for

probe

compensation.

Output:

0.2Vand2V

+1

%.

Line

voltage:

110,

125,

220,

240

V~

±10%.

Line

frequency:

50Hz

to

400Hz.

Power

consumption

:

=

37

Watt

(at

50

Hz).

Max.

ambient

temperature:

-(-10°C...-T40°C.

Protective

system:

Safety

Class

I

(lEC

348).

Weight:

approx.

7.5kg.

Colour:

techno-brown.

Cabinet:

W

285,

H

145,

D

380mm.

Lockable

tilt

handle.

20

MHz

Standard

Oscilloscope

2

Channels,

max.

1

mV/div.

sensitivity;

Component

Tester

Timebase:

0,1s/div.

to

20ns/div.;

Variable

Holdoff;

Alternate

Triggering;

Triggering:

DC-40MHz;

TV

Sync

Separator;

Trigger

LED

The

HM

203-7

is

Western

Europe's

best

selling

oscilloscope

because

it

responds

thoroughly

to

customer

demands

for

reliability,

superior

perfor¬

mance,

and

ease

of

operation.

The

outstanding

transient

response

of

the

HM

203-7,

particularly

when

displaying

square

wave

signals,

is

one

of

the

pre-eminent

features

of

this

quality

instrument,

the

integrity

of

the

signals

reproduced

by

this

oscilloscope

reflect

a

dedication

to

engineering

excellence

normally

only

found

in

expensive

labora¬

tory

instruments.

As

an

aid

to

ensure

the

correct

polarities

when

displaying

the

sum,

difference,

or

video

signals,

an

"invert"

control

is

provided

on

channel

II.

Technically

advanced

triggering

circuits

enable

the

user

to

attain

clear,

stable

displays

from

DC

to

over

40

MHz,

with

input

levels

as

low

as

0.5

divisions.

The

Holdoff

control

enables

even

complex

asynchronous

waveforms

to

be

solidly

displayed.

Trigger

action

is

indicated

by

an

LED,

which

illuminates

whenever

the

trigger

threshold

point

is

crossed.

And

for

the

display

of

video

signals,

the

HM

203-7

has

a

low

distortion

active

TV

sync

separator,

which

allows

for

auto¬

matic

synchronizing

with

line

and

frame

frequencies.

"Alternate

triggering"

mode

enables

the

display

of

two

asynchronous

signals

simulteneously.

The

CRT's

8x10

cm

internal

graticule

enhances

parallax-free

viewing

over

a

wide

field.

In

addition,

the

CRT

is

fully

shielded

with

mumetal

to

prevent

display

distortion

in

the

presence

of

magnetic

fields.

As

a

practical,

built-in

feature,

the

component

tester

enables

the

operator

to

quickly

identify

faulty

semiconductors

and

a

large

variety

of

individual

compo¬

nents,

both

in

circuit

and

out.

The

HM203-7

was

specifically

designed

for

use

in

production

lines,

general

service

applications,

and

for

technical

training

facilities.

The

multiplicity

of

display

modes,

the

easy-to-understand

front

panel,

and

the

operational

simplicity

of

the

HM203-7

make

it

also

an

ideal

training

scope

for

educational

purposes.

Accessories

supplied

Two

10:1

probes.

Line

cord.

Operators

Manual.

Subject

to

change

without

notice.

OSCILLOSCOPE

ACCESSORIES

Test

Cable

Banana-BNC

HZ32

Coaxial

test

cable;

length

1.15m,

characteristic

impedance

50fl.

Cable

capacitance

120pF.

Input

voltage

max.

500Vp.

Test

Cable

BNC

-

BNC

HZ34

Coaxial

test

cable;

length

1

m,

characteristic

impedance

50J1.

Cable

capacitance

126pF.

Input

voltage

max.

500Vp.

Adapter

Banana-BNC

HZ20

Two

4mm

binding

posts

(19mm

between

centers)

to

standard

BNC

male

plug.

Input

voltage

max.

500Vp.

son

Through-Termination

HZ22

For

terminating

systems

with

50

Q

characteristic

impedance.

Modular

Probes

Maximum

load

2W.

Max.

voltage

lOVp^s-

The

clear

advantage

over

ordinary

probes

are

field

replaceable

parts

and

the

HF-compensation

feature

on

the

10:1

attenuator

pro¬

bes.

For

the

first

time,

probes

in

this

price

range

allow

adjustments

of

their

FIF-characteristics

to

match

individually

the

input

imped¬

ance

of

each

scope.

This

is

particularly

important

for

scopes

with

higher

bandwidths

(>50MFIz),

as

otherwise

strong

overshoot

or

rounding

may

occur,

when

measuring

fast-rising

square

waves.

An

exact

FIF-compensation,

however,

is

only

possible

with

square-

wave

generators

having

a

risetime

<5ns.

Most

FIAMEG

scopes

already

feature

such

a

calibration

generator.

For

other

oscillo¬

scopes,

it

is

available

as

accessory

item

FIZ60-2.

At

present

the

following

Modular

Probes

are

available

(FIZ36

without

HF-com-

pensation);

Type

HZ36

selectable

Attenuation

Ratio

1:1/10:1

Bandwidth

min.

(MFIz)

10/100

Risetime

(ns)

35/3.5

Inp,

Capacitance

(pF)

47/18

Inp.

Resistance

(Mil)

1/10

Inp.

Voltage

max.

(Vp)

600

Cable

Length

(m)

1.5

Spare

Cable

for

HZ36

Spare

Cable

for

HZ51.

HZ54

Sparepart

Kit

(2

sprung

hooks.

2

HZ51

HZ52

HZ53

HZ54

selectable

10:1

10:1

(HF)

100:1

1:1/10:1

150

250

150

10/150

<2

<1.4

<2

35/<2

16

16

6,5

40/18

10

10

100

1/10

600

600

1200

600

1.2

1.5

1,5

1.2

HZ

39

HZ57

tips,

1

ground

cable)

HZ40

Demodulator

Probe

HZ55

Special

probe

for

AM-demodulation

and

wobbulator

measure¬

ments.

HF-Bandwidth

lOOkFIz

-

500MFIz

(±1dB).

AC

Input

Volt¬

age

250mV

-

50Vrms-

DC

Isolation

Voltage

200V

DC

including

peak

AC.

Cable

length

1.2m.

High

Voltage

Probe

HZ58

For

measurement

of

voltages

up

to

15kVpp.

Input

resistance

approx.

500mQ.

Recommended

load

resistance)

MQ/10MQ

(switchable).

Attenuation

ratio

1000:1.

Bandwidth

1

MFIz.

Cable

length

1.5

m.

BNC

connector.

Carrying

Cases

For

HM103

HZ95

For

HM

203,

HM204,

HM205,

HM208,

HM408,

HM604,

HM605

and

HM

1005

HZ96

Viewing

Hood

HZ47

ForHM203,

HM204,

HM205,

HM208,

HM408,

HM604,

HM605

and

HM

1005

Scope-Tester

HZ

6

O

-2

For

Checking

the

Y

amplifier,

timebase,

and

compensation

of

all

probes,

the

HZ

60-2

is

a

crystal-controlled,

fast

rising

(typ.

3

ns)

square-wave

generator

with

switchable

frequencies

of

DC,

1-10-

100Hz,

1-IO-IOOkHz,

and

1

MHz.

Three

BNC

outputs

provide

sig¬

nals

of

25

mVpp

into

50

Q,

0.25

Vpp

and

2.5

Vpp

(open

circuit

for

10x

and

lOOx

probes);

accuracy

±1%.

Battery-powered.

Component-Tester

HZ65

Indispensable

for

trouble-shooting

in

electronic

circuits.

Single

component

and

in-circuit

tests

are

both

possible.

The

HZ65

oper¬

ates

with

all

scopes,

which

can

be

switched

to

X-Y

operation

(ext.

horizontal

deflection).

Non-destructive

tests

can

be

carried

out

on

almost

all

semiconductors,

resistors,

capacitors,

and

coils.

Two

sockets

provide

for

quick

testing

of

the

3

junction

areas

in

any

small

power

transistor.

Other

components

are

connected

by

using

2

banana

jacks.

Test

leads

supplied.

Examples

of

Test

Displays:

Short

circuit

CapacitorSS^F

Junction

E-C

Z-Diode<8V

Printed

in

West

Germany

5/90

zi

Operating

Instructions

General

Information

Safety

This

oscilloscope

is

easy

to

operate.

The

logical

arrange¬

ment

of

the

controls

allows

anyone

to

become

familiar

with

the

operation

of

the

instrument

after

a

short

time,

however,

experienced

users

are

also

advised

to

read

through

these

instructions

so

that

all

functions

are

understood.

Immediately

after

unpacking,

the

instrument

should

be

checked

for

mechanical

damage

and

loose

parts

in

the

in¬

terior.

If

there

is

transport

damage,

the

supplier

must

be

in¬

formed

immediately.

The

instrument

must

then

not

be

put

into

operation.

Check

that

the

instrument

is

set

to

the

correct

mains/line

voltage.

If

not,

refer

to

instructions

on

page

M2.

Use

of

tilt

handle

To

view

the

screen

from

the

best

angle,

there

are

three

dif¬

ferent

positions

(C,

D,

E)forsetting

up

the

instrument.

If

the

instrument

is

set

down

on

the

floor

after

being

carried,

the

handle

remains

automatically

in

the

upright

carrying

posi¬

tion

(A).

In

order

to

place

the

instrument

onto

a

horizontal

surface,

the

handle

should

be

turned

to

the

upper

side

of

the

oscillo¬

scope

(C).

For

the

D

position

(10°

inclination),

the

handle

should

be

turned

in

the

opposite

direction

out

of

the

carry¬

ing

position

until

it

locks

in

place

automatically

underneath

the

instrument.

For

the

E

position

(20°

inclination),

the

handle

should

be

pulled

to

release

it

from

the

D

position

and

swing

backwards

until

it

locks

once

more.

The

handle

may

also

be

set

to

a

position

for

horizontal

carry¬

ing

by

turning

it

to

the

upper

side

to

lock

in

the

B

position.

At

the

same

time,

the

instrument

must

be

moved

upwards,

because

otherwise

the

handle

will

jump

back.

This

instrument

has

been

designed

and

tested

in

accor¬

dance

with

lEC

Publication

348,

Safety

Requirements

for

Eiectronic

Measuring

Apparatus,

and

has

left

the

factory

in

a

safe

condition.

The

present

instruction

manual

contains

important

information

and

warnings

which

have

to

be

fol¬

lowed

by

the

user

to

ensure

safe

operation

and

to

retain

the

oscilloscope

in

safe

condition.

The

case,

chassis

and

all

measuring

terminals

are

connected

to

the

protective

earth

contact

of

the

appliance

inlet.

The

instrument

operates

ac¬

cording

to

Safety

C/ass

/

(

three-conductor

power

cord

with

protective

earthing

conductor

and

a

plug

with

earthing

con¬

tact).

The

mains/line

plug

shall

only

be

inserted

in

a

socket

outlet

provided

with

a

protective

earth

contact.

The

protec¬

tive

action

must

not

be

negated

by

the

use

of

an

extension

cord

without

a

protective

conductor.

Warningl

Any

interruption

of

the

protective

conductor

inside

or

outside

the

instrument

or

disconnection

of

the

protective

earth

terminai

is

iikely

to

make

the

instru¬

ment

dangerous.

Intentional

interruption

of

the

protec¬

tive

earth

connection

is

prohibited.

The

mains/line

piug

should

be

inserted

before

connections

are

made

to

measuring

circuits.

The

grounded

accessible

metal

parts

(case,

sockets,

jacks)

and

the

mains/line

supply

contacts

(line,

neutral)

of

the

in¬

strument

have

been

tested

against

insulation

breakdown

with

2000Vr.m.s.

(50Hz).

Under

certain

conditions,

50

Hz

or

60

Hz

hum

voltages

can

occur

in

the

measuring

circuit

due

to

the

interconnection

with

other

mains/line

powered

equipment

or

instruments.

This

can

be

avoided

by

using

an

isolation

transformer

(Safety

Class

II).

When

displaying

waveforms

where

the

"low-level"

side

of

the

signal

is

at

a

high

potential,

even

with

the

use

of

a

protective

isolation

transformer,

it

should

be

noted

that

this

potential

is

connected

to

the

oscillo¬

scope's

case

and

other

accessible

metal

parts.

High

volt¬

ages

are

dangerous.

In

this

case,

special

safety

precautions

are

to

be

taken,

which

must

be

supervised

by

qualified

per¬

sonnel

if

the

voltage

is

higher

than

42

V.

Most

cathode-ray

tubes

develop

X-rays.

However,

the

dose

equivalent

rate

falls

far

below

the

maximum

per¬

missible

value

of

36pA/kg

(O.SmR/h).

Whenever

it

is

likely

that

protection

has

been

impaired,

the

instrument

shall

be

made

inoperative

and

be

secured

against

any

unintended

operation.

The

protection

is

likely

to

be

impaired

if,

for

example,

the

instrument

-

shows

visible

damage,

-

fails

to

perform

the

intended

measurements,

-

has

been

subjected

to

prolonged

storage

under

un¬

favourable

conditions

(e.g.

in

the

open

or

in

moist

envi¬

ronments),

-

has

been

subject

to

severe

transport

stress

(e.g.

in

poor

packaging).

Subject

to

change

without

notice

Ml

Operating

conditions

Maintenance

The

instrument

has

been

designed

for

indoor

use.

The

permissible

ambient

temperature

range

during

opera¬

tion

is

-I-10°C...

-t-40°C.

It

may

occasionally

be

subjected

to

temperatures

between

-l-10°Cand

-10°C

without

degrad¬

ing

its

safety.

The

permissible

ambient

temperature

range

for

storage

or

transportation

is

-40°C

...

-I-70°C.

The

maximum

operating

altitude

is

up

to

2200

m

(non¬

operating

15000

m).

The

maximum

relative

humidity

is

up

to

80%.

If

condensed

water

exists

in

the

instrument

it

should

be

acclimatized

before

switching

on.

In

some

cases

(e.g.

extremely

cold

oscilloscope)

two

hours

should

be

allowed

before

the

instrument

is

put

into

operation.

The

instrument

should

be

kept

in

a

clean

and

dry

room

and

must

not

be

operated

in

explosive,

corrosive,

dusty,

or

moist

environ¬

ments.

The

oscilloscope

can

be

operated

in

any

position,

but

the

convection

cooling

must

not

be

impaired.

The

ven¬

tilation

holes

may

not

be

covered.

For

continuous

opera¬

tion

the

instrument

should

be

used

in

the

horizontal

posi¬

tion,

preferably

tilted

upwards,

resting

on

the

tilt

handle.

The

specifications

stating

tolerances

are

only

valid

if

the

instrument

has

warmed

up

for

30

minutes

at

an

ambient

temperature

between

-h15C°and

+30C°.

Val¬

ues

not

stating

tolerances

are

typical

for

an

average

instrument.

Guarantee

Each

instrument

runs

through

a

quality

test

with

10

hour

burn-in

before

leaving

the

production.

Practically

every

early

failure

is

detected

in

intermittent

operation

by

this

method.

However,

it

is

possible

that

a

component

fails

only

after

a

lengthy

operating

period.

Therefore

a

functional

guaran¬

tee

of

2

years

is

given

for

all

units.

The

condition

for

this

is

that

no

modifications

have

been

made

in

the

instrument.

In

the

case

of

shipments

by

post,

rail

or

carrier

it

is

recom¬

mended

that

the

original

packing

is

carefully

preserved.

Transport

damages

and

damage

due

to

gross

negligence

are

not

covered

by

the

guarantee.

In

the

case

of

a

complaint,

a

label

should

be

attached

to

the

housing

of

the

instrument

which

describes

briefly

the

faults

observed.

If

at

the

same

time

the

name

and

telephone

number

(dialing

code

and

telephone

or

direct

number

or

department

designation)

is

stated

for

possible

queries,

this

helps

towards

speeding

up

the

processing

of

guarantee

claims.

Various

important

properties

of

the

oscilloscope

should

be

carefully

checked

at

certain

intervals.

Only

in

this

way

is

it

largely

certain

that

all

signals

are

displayed

with

the

accu¬

racy

on

which

the

technical

data

are

based.

The

test

methods

described

in

the

test

plan

of

this

manual

can

be

performed

without

great

expenditure

on

measuring

instru¬

ments.

However,

purchase

of

the

new

HAM

EG

scope

test¬

er

HZ

60,

which

despite

its

low

price

is

highly

suitable

for

tasks

of

this

type,

is

very

much

recommended.

The

exterior

of

the

oscilloscope

should

be

cleaned

regularly

with

a

dusting

brush.

Dirt

which

is

difficult

to

remove

on

the

casing

and

handle,

the

plastic

and

aluminium

parts,

can

be

removed

with

a

moistened

cloth

(99%

water

-Fl

%

mild

detergent).

Spirit

or

washing

benzine

(petroleum

ether)

can

be

used

to

remove

greasy

dirt.

The

screen

may

be

cleaned

with

water

or

washing

benzine

(but

not

with

spirit

(alcohol)

or

solvents),

it

must

then

be

wiped

with

a

dry

clean

lint-free

cloth.

Under

no

circumstances

may

the

cleaning

fluid

get

into

the

instrument.

The

use

of

other

cleaning

agents

can

attack

the

plastic

and

paint

surfaces.

Switching

over

the

mains/line

voltage

The

instrument

is

set

for

220

V

line

voltage

on

delivery.

It

can

be

switched

over

to

other

voltages

at

the

fuse

holder

combined

with

the

3-pole

appliance

inlet

at

the

rear

of

the

instrument.

Firstly

the

fuse

holder

printed

with

the

voltage

values

is

removed

using

a

small

screw

driver

and

-

if

required

-

provided

with

another

fuse.

Refer

to

the

table

below

for

the

prescribed

value

of

the

fuse.

Then

replace

the

fuse

holder

so

that

the

impressed

white

triangle

points

to

the

desired

voltage.

Here

pay

attention

that

the

cover

plate

is

also

correctly

engaged.

The

use

of

repaired

fuses

or

short

circuiting

the

fuse

holder

is

not

allowed.

Damage

arising

because

of

this

is

not

covered

by

the

guarantee.

220

R

\

ir>

N>

CM

1-

o

0

0

1

oil

V-

y

Fuse

type:

Size

5

x

20

mm;

250

V~,

C;

lEC

127,

Sheet

III;

DIN

sheet

3).

Cutoff:

time

lag

(T).

Line

voltage

110V~±10%

125V~±10%

220V~±10%

240V~±10%

41

662

(possibly

DIN

41

571

Fuse

rating

T0.63

A

T0.63

A

T0.315A

T0.315A

M2

Subject

to

change

without

notice

Type

of

the

signal

voltage

With

the

HM

203-7,

practically

all

periodically

repeating

sig¬

nals

with

the

frequency

spectrum

below

20

MHz

can

be

examined.

The

display

of

simple

electrical

processes,

such

as

sinusoidal

RF

and

LF

signals

or

line

frequency

hum

volt¬

ages

is

straightforward.

When

recording

square-wave

or

pulse-type

signal

voltages,

it

must

be

noted

that

their

har¬

monics

must

also

be

transmitted.

The

repetition

frequency

of

the

signal

must

therefore

be

significantly

smaller

than

the

upper

limit

frequency

of

the

vertical

amplifier.

Accurate

evaluation

of

such

signals

is

only

possible

up

to

approxi¬

mately

2

MHz

repetition

frequency.

Displaying

composite

signals

can

be

difficult,

especially

if

they

contain

no

repetive

higher

amplitude

content

which

can

be

used

for

triggering.

This

is

the

case

with

bursts,

for

instance.

To

obtain

a

well-triggered

display

in

this

case,

the

assistance

of

the

variable

holdoff

and/or

variable

time

con¬

trol

may

be

required.

Television

video

signals

are

relatively

easyto

trigger

using

the

built-in

TV-Sync-Separator

with

correct

trigger

slope

setting.

For

optional

operation

as

a

DC

or

AC

voltage

amplifier,

the

vertical

amplifier

input

is

provided

with

a

DC/AC

switch.

The

DC

position

should

only

be

used

with

a

series-con¬

nected

attenuator

probe

or

at

very

low

frequencies

or

if

the

measurement

of

the

DC

voltage

content

of

the

signal

is

absolutely

necessary.

When

displaying

very

low

frequency

pulses,

the

flat

tops

may

be

sloping

with

AC

coupling

of

the

vertical

amplifier

(AC

limit

frequency

approx.

1.6

Hz

for

-3dB).

In

this

case,

DC

operation

is

preferred,

provided

the

signal

voltage

is

not

superimposed

on

a

too

high

DC

level.

Otherwise

a

capacitor

of

adequate

capacitance

must

be

connected

to

the

input

of

the

vertical

amplifier

with

DC

coupling.

This

capacitor

must

have

a

sufficiently

high

breakdown

voltage

rating.

DC

cou¬

pling

is

also

recommended

for

the

display

of

logic

and

pulse

signals,

especially

if

the

pulse

duty

factor

changes

con¬

stantly.

Otherwise

the

display

will

move

upwards

or

down¬

wards

at

each

change.

Pure

direct

voltages

can

only

be

measured

with

DC-coupling.

Amplitude

Measurements

In

general

electrical

engineering,

alternating

voltage

data

normally

refers

to

effective

values

(rms

=

root-mean-

square

value).

However,

for

signal

magnitudes

and

voltage

designations

in

oscilloscope

measurements,

the

peak-to-

peak

voltage

(Vpp)

value

is

applied.

The

latter

corresponds

to

the

real

potential

difference

between

the

most

positive

and

most

negative

points

of

a

signal

waveform.

If

a

sinusoidal

waveform,

displayed

on

the

oscilloscope

screen,

is

to

be

converted

into

an

effective

(rms)

value,

the

resulting

peak-to-peak

value

must

be

divided

by

2xy~2

=

2.83.

Conversely,

it

should

be

observed

that

sinusoidal

volt¬

ages

indicated

in

(Veff)

have

2.83

times

the

potential

dif¬

ference

in

Vpp.

The

relationship

between

the

different

volt¬

age

magnitudes

can

be

seen

from

the

following

figure.

Voltage

values

of

a

sine

curve

V,ms

=

effective

value;

Vp

=

simple

peak

or

crest

value:

Vpp

=

peak-to-peak

value:

'^mom

=

momentary

value.

The

minimum

signal

voltage

which

must

be

applied

to

the

Y

input

for

a

trace

of

1

div.

height

is

ImVpp

when

the

Y

MAG.xS

pushbutton

is

depressed,

the

VOLTS/DIV.

switch

is

set

to

BmV/div.,

and

the

vernier

is

set

to

CAL

by

turning

the

fine

adjustment

knob

of

the

VOLTS/DIV.

switch

clockwise

all

the

way.

However,

smaller

signals

than

this

may

also

be

displayed.

The

deflection

coefficients

on

the

input

attenuators

are

indicated

in

mV/div.

or

V/div.

(peak-to-peak

value).

The

magnitude

of

the

applied

voltage

is

ascertained

by

multiplying

the

selected

deflection

coefficient

by

the

vertical

display

height

in

div.

If

an

attenuator

probe

xIOis

used,

a

further

multiplica¬

tion

by

a

factor

of

10

is

required

to

ascertain

the

correct

voltage

value.

For

exact

amplitude

measurements,

the

variable

con¬

trol

on

the

attenuator

switch

must

be

set

to

its

calibra¬

ted

detent

CAL.

When

turning

the

variable

control

ccw,

the

sensitivity

will

be

reduced

by

a

factor

of

2.5.

Therefore

every

intermediate

value

is

possible

within

the

1-2-5

sequence.

With

direct

connection

to

the

vertical

input,

signals

up

to

lOOVpp

may

be

displayed

(attenuator

set

to

5V/div.,

vari¬

able

control

to

left

stop).

With

the

designations

H

=

display

height

in

div.,

U

=

signal

voltage

in

Vpp

at

the

vertical

input,

D

=

deflection

coefficient

in

V/div.

at

attenuator

switch,

the

required

quantity

can

be

calculated

from

the

two

given

quantities:

U-DH

H.U

D

=

U

Subject

to

change

without

notice

M3

203-7

However,

these

three

values

are

not

freely

selectable.

They

have

to

be

within

the

following

limits

(trigger

threshold,

accuracy

of

reading):

H

between

0.5

and

8div.,

if

possible

3.2

to

8div.,

U

between

1

mVpp

and

40Vpp,

D

between

1

mV/div.

and

5V/div.

in

1-2-5

sequence.

Examples:

Set

deflection

coefficient

D

=

50mV/div.

^

0.05

V/div.,

observed

display

height

H

=

4.6

div.,

required

voltage

U

=

0.05

-4.6

=

0.23

Vpp.

Input

voltage

U

=

5Vpp,

set

deflection

coefficient

D

=

1

V/div.,

required

display

height

H

=

5:1

=

5div.

Signal

voltage

U

=

220\/,^,-2-VY

=

622

Vpp

(voltage

>

40Vpp,

with

probe

x

100:

U

=

6.22

Vpp),

desired

display

height

H

=

min.

3.2div.,

max.

8div.,

max.

deflection

coefficient

D

=

6.22:3.2

=

1.94V/div.,

min.

deflection

coefficient

D

=

6.22:8

=

0.78V/div.,

adjusted

deflection

coefficient

D

=

1

V/div.

If

the

applied

signal

is

superimposed

on

a

DC

(direct

voltage)

level

the

total

value

(DC

+

peak

value

of

the

alternating

voltage)

of

the

signal

across

the

Y-input

must

not

exceed

±400V

(see

figure).

This

same

limit

applies

to

normal

xIO

attenuator

probes,

the

attenuation

ratio

of

which

allows

signal

voltages

up

to

approximately

400Vpp

to

be

evaluated.

Voltages

of

up

to

approximately

2,400Vpp

may

be

measured

by

using

the

HZ53

high

voltage

probe

which

has

an

attenuation

ratio

of

100:1.

It

should

be

noted

that

its

ACpeak

value

is

derated

at

higher

frequencies.

If

a

normal

xIO

probe

is

used

to

measure

high

voltages

there

is

the

risk

that

the

compensation

trimmer

bridging

the

attenuator

series

resistor

will

break

down

causing

damage

to

the

input

of

the

oscilloscope.

However,

if

for

example

only

the

residual

ripple

of

a

high

voltage

is

to

be

displayed

on

the

oscilloscope,

a

normal

xIO

probe

is

sufficient.

In

this

case,

an

appropriate

high

voltage

capacitor

(approx.

22-

68

nF)

must

be

connected

in

series

with

the

input

tip

of

the

probe.

Voltage

Total

value

of

input

voltage

The

dotted

line

shows

a

voltage

alternating

at

zero

volt

level.

When

superim¬

posed

a

DC

level,

the

addition

of

the

positive

peak

and

the

DC

voltage

results

in

the

max.

voltage

(DC

-i-

ACpeaJ.

It

is

very

important

that

the

oscilloscope

input

coupling

is

set

to

DC,

if

an

attenuator

probe

is

used

for

voltages

higher

than

400V

(see

page

IVI6:

Connection

of

Test

Signal).

With

Y-POS.

control

(input

coupling

to

GD)

it

is

possible

to

set

a

horizontal

graticule

line

as

reference

line

for

ground

potential

before

the

measurement.

It

can

lie

below

or

above

the

horizontal

central

line

according

to

whether

posi¬

tive

and/or

negative

deviations

from

the

ground

poterntial

are

to

be

measured.

Certain

switchable

xIO/xl

attenuator

probes

also

have

a

built-in

ground

reference

switch

posi¬

tion.

Time

Measurements

As

a

rule,

most

signals

to

be

displayed

are

periodically

repeating

processes,

also

called

periods.

The

number

of

periods

per

second

is

the

repetition

frequency.

Depending

on

the

time

base

setting

of

the

TIME/DIV.

switch,

one

or

several

signal

periods

or

only

a

part

of

a

period

can

be

dis¬

played.

The

time

coefficients

are

stated

in

ms/div.

and

\>s/

div.

on

the

TIME/DIV.-switch.

The

scale

is

accordingly

divided

into

two

fields.

The

duration

of

a

signal

period

or

a

part

of

it

is

deter¬

mined

by

multipiying

the

reievant

time

(horizontal

dis¬

tance

in

div.)

by

the

time

coefficient

set

on

the

TIME/

DlM.-switch.

The

variabie

time

control

(identified

with

an

arrow

knob

cap)

must

be

in

its

caiibrated

position

CAL.

(arrow

pointing

horizontally

to

the

right).

With

the

designations

L

=

displayed

wave

length

in

div.

of

one

period,

T

=

time

In

seconds

for

one

period,

F

=

recurrence

frequency

in

Hz

of

the

signal,

Tc

=

time

coefficient

in

s/div.

on

timebase

switch

and

the

relation

F

=

1

/T,

the

following

equations

can

be

stated;

H

II

1“

t-

II

II

P-lH

F

-

,

1_

L

-

.1

T

-

^

L’Tc

F-Tc

LF

With

depressed

X-MAG.

x10

pushbutton

the

Tg

value

must

be

divided

by

10.

However,

these

four

values

are

not

freely

selectable.

They

have

to

be

within

the

following

limits:

L

between

0.2

and

lOdiv.,

if

possible

4

to

lOdiv.,

T

between

0.02

[xs

and

1

s,

F

between

0.5

Hz

and

20

MHz,

Tc

between

0.2[is/div.

and

0.1

s/div.

in

1-2-5

sequence

(with

X-MAG.

xIO

in

out

position),

and

Tc

between

20ns/div.

and

10

ms/div.

in

1-2-5

sequence

(with

pushed

X-MAG.

x

10

pushbutton).

M4

203-7

Subject

to

change

without

notice

Examples:

Displayed

wavelength

L

=

7div.,

set

time

coefficient

=

0.2

^is/div.,

required

period

T

=

7

0.2-10”®

=

1.4(is

required

rec.

freq.

F

=

1

;(1.4-10”®)

=

714

kHz.

Signal

period

T

=

0.5s,

set

time

coefficient

=

0.2s/div.,

required

wavelength

L

=

0.5:0.2

=

2.5div..

Displayed

ripple

wavelength

L

=

1

div.,

set

time

coefficient

=

10

ms/div.,

required

ripple

freq.

F

=

1

:

(1

-lO-IO”®)

=

100

Hz.

TV-line

frequency

F

=

15

625

Hz,

set

time

coefficient

Tc

=

lO^rs/div.,

required

wavelength

L

=

1

:(15

625

-10“®)

=

6.4div..

Sine

wavelength

L

=

min.

4div.,

max.

10div.,

Frequency

F

=

1

kHz,

max.

time

coefficient

T;,

=

1:

(4-10®)

=

0.25

ms/div.,

min.

time

coefficient

Tc

=

1

:(10-10®)

=

0.1

ms/div.,

set

time

coefficient

=

0.2

ms/div.,

required

wavelength

L

=

1

(10®

0.2

10“®)

=

5div.

Displayed

wavelength

L

=

O.Sdiv.,

set

time

coefficient

T,,

=

0.5pis/div.,

pressedX-MAG.

xIO

button:

=

0.05^is/div.,

required

rec.

freq.

F

=

1:

(0.8-0.05-10“®)

=

25

MHz,

required

period

T

=

1:

(25

-10®)

=

40

ns.

If

the

time

is

relatively

short

as

compared

with

the

complete

signal

period,

an

expanded

time

scale

should

always

be

applied

(X-MAG.

xIO

button

pressed).

In

this

case,

the

ascertained

time

values

have

to

be

divided

by

10.

The

time

interval

of

interest

can

be

shifted

to

the

screen

center

using

the

X-POS.

control.

The

following

figure

shows

correct

positioning

of

the

oscil¬

loscope

trace

for

accurate

risetime

measurement.

100

%

90%

10

%

0

With

a

time

coefficient

of

0.2ns/div.

and

pushed

X-MAG

xIO

button

the

example

shown

in

the

above

figure

results

in

a

measured

total

risetime

of

t,ot

=

1.6div.-0.2ns/div.:

10

=

32ns

When

very

fast

risetimes

are

being

measured,

the

rise-

times

of

the

oscilloscope

amplifier

and

of

the

attenuator

probe

has

to

be

deducted

from

the

measured

time

value.

The

risetime

of

the

signal

can

be

calculated

using

the

fol¬

lowing

formula.

In

this

ttot

is

the

total

measured

risetime,

tosc

is

the

risetime

of

the

oscilloscope

amplifier

(approx.

17,5

ns),

and

tp

the

risetime

of

the

probe

(e.g.

=

2

ns).

If

ttot

is

greater

than

100

ns,

then

t^t

can

be

taken

as

the

risetime

of

the

pulse,

and

calculation

is

unnecessary.

Calculation

of

the

example

in

the

figure

above

results

in

a

signal

risetime

When

investigating

pulse

or

square

waveforms,

the

critical

feature

is

the

risetime

of

the

voltage

step.

To

ensure

that

transients,

ramp-offs,

and

bandwidth

limits

do

not

unduly

influence

the

measuring

accuracy,

the

risetime

is

generally

measured

between

70%

and

90%

of

the

vertical

pulse

height.

For

peak-to-peak

signal

amplitude

of

6div.

height,

which

are

symmetrically

adjusted

to

the

horizontal

center

line,

the

internal

graticule

of

the

CRT

has

two

horizontal

dot¬

ted

lines

±2.4div.

from

the

center

line.

Adjust

the

Y

attenuator

switch

with

its

variable

control

together

with

the

Y-POS.

control

so

that

the

pulse

height

is

precisely

aligned

with

these

0

and

100

%

lines.

The

10

%

and

90

%

points

of

the

signal

will

now

coincide

with

the

two

lines,

which

have

a

distance

of

±2.4div.

from

the

horizontal

center

line

and

an

additional

subdivision

of

0.2

div.

The

risetime

is

given

by

the

product

of

the

horizontai

distance

in

div.

between

these

two

coincidence

points

and

the

time

coefficient

setting.

If

magnification

is

used,

this

product

must

be

divided

by

10.

The

/a/Zf/meof

a

pulsecan

also

be

measured

by

using

this

method.

tr

=

y

32®

-

17.5®

-

2®

=

26.27

ns

The

measurement

of

the

rise

or

fall

time

is

not

limited

to

the

trace

dimensions

shown

in

the

above

diagram.

It

is

only

par¬

ticularly

simple

in

this

way.

In

principle

it

is

possible

to

measure

in

any

display

position

and

at

any

signal

amplitude.

It

is

only

important

that

the

full

height

of

the

signal

edge

of

interest

is

visible

in

its

full

length

at

not

too

great

steepness

and

that

the

horizontal

distance

at

10%

and

90%

of

the

amplitude

is

measured.

If

the

edge

shows

rounding

or

over¬

shooting,

the

100%

should

not

be

related

to

the

peak

val¬

ues

but

to

the

mean

pulse

heights.

Breaks

or

peaks

(glitches)

next

to

the

edge

are

also

not

taken

into

account.

With

very

severe

transient

distortions,

the

rise

and

fall

time

measurement

has

little

sense.

For

amplifiers

with

approxi¬

mately

constant

group

delay

(therefore

good

pulse

trans¬

mission

performance)

the

following

numerical

relationship

between

rise

time

tr

{in

ns)

and

bandwidth

B

(in

MHz)

applies;

tr

=

3|0

B

tr

Subject

to

change

without

notice

M5

203-7

Connection

of

Test

Signal

Caution:

When

connecting

unknown

signals

to

the

oscillo¬

scope

input,

always

use

automatic

triggering

and

set

the

DC-AC

input

coupling

switch

to

AC.

The

attenuator

switch

should

initially

be

set

to

5

V/div..

Sometimes

the

trace

will

disappear

after

an

input

signal

has

been

applied.

The

attenuator

switch

must

then

be

turned

back

to

the

left,

until

the

vertical

signal

height

is

only

3-8div.

With

a

signal

amplitude

greater

than

lOOVpp,

an

attenuator

probe

must

be

inserted

before

the

oscilloscope's

vertical

input.

If,

after

applying

the

signal,

the

trace

is

nearly

blanked,

the

period

of

the

signal

is

probably

substantially

longer

than

the

set

value

on

the

TIME/DIV.

switch.

It

should

be

turned

to

the

left

to

an

adequately

larger

time

coefficient.

The

signal

to

be

displayed

can

be

connected

directly

to

the

Y-input

of

the

oscilloscope

with

a

shielded

test

cable

such

as

HZ

32

and

HZ

34

or

attenuated

through

a

xIO

or

xlOO

attenuator

probe.

The

use

of

test

cables

with

high

imped¬

ance

circuits

is

only

recommended

for

relatively

low

fre¬

quencies

(up

to

approx.

50

kHz).

For

higher

frequencies,

the

signal

source

must

be

of

low

impedance,

i.e.

matched

to

the

characteristic

resistance

of

the

cable

(as

a

rule

50

Ohm).

Especially

when

transmitting

square

and

pulse

signals,

a

resistor

equal

to

the

characteristic

impedance

of

the

cable

must

also

be

connected

across

the

cable

directly

at

the

Y-

input

of

the

oscilloscope.

When

using

a

50

Ohm

cable

such

as

the

HZ

34,

a

50

Ohm

through

termination

type

HZ22

is

available

from

HAMEG.

When

transmitting

square

signals

with

short

rise

times,

transient

phenomena

on

the

edges

and

top

of

the

signal

may

become

visible

if

the

correct

ter¬

mination

is

not

used.

A

terminating

resistance

is

some¬

times

recommended

with

sine

signals

as

well.

Certain

amplifiers,

generators

or

their

attenuators

maintain

the

nominal

output

voltage

independent

of

frequency

only

if

their

connection

cable

is

terminated

with

the

prescribed

resistance.

Here

it

must

be

noted

that

the

terminating

resis¬

tor

HZ

22

will

only

dissipate

a

maximum

of

2

Watts.

This

power

is

reached

with

10

V^ms

or

-

at

28.3

Vpp

with

sine

sig¬

nal.

If

a

x10

or

x100

attenuator

probe

is

used,

no

termination

is

necessary.

In

this

case,

the

connecting

cable

is

matched

directly

to

the

high

impedance

input

of

the

oscilloscope.

When

using

attenuators

probes,

even

high

internal

imped¬

ance

sources

are

only

slightly

loaded

(approx.

10

MQ

II

16

pF

or

100

MQ

II

7

pF

with

HZ

53).

Therefore,

if

the

voltage

loss

due

to

the

attenuation

of

the

probe

can

be

compen¬

sated

by

a

higher

amplitude

setting,

the

probe

should

always

be

used.

The

series

impedance

of

the

probe

pro¬

vides

a

certain

amount

of

protection

for

the

input

of

the

ver¬

tical

amplifier.

Because

of

their

separate

manufacture,

all

attenuator

probes

are

only

partially

compensated,

therefore

accurate

compensation

must

be

performed

on

the

oscillo¬

scope

(see

"Probe

compensation"

page

M7).

Standard

attenuator

probes

on

the

oscilloscope

normally

reduce

its

bandwidth

and

increase

the

rise

time.

In

all

cases

where

the

oscilloscope

band

width

must

be

fully

utilized

(e.g.

for

pulses

with

steep

edges)

we

strongly

advise

using

the

modular

probes

HZ

51

(x10)

HZ52{x^

0

HF)

and

HZ54

(x1

and

xIO,

see

oscilloscope

accessories,

page

Z1).

This

can

save

the

purchase

of

an

oscilloscope

with

larger

bandwidth

and

has

the

advantage

that

defective

compo¬

nents

can

be

ordered

from

HAMEG

and

replaced

by

one¬

self.

The

probes

mentioned

havea

HF-calibration

in

addition

to

low

frequency

calibration

adjustment.

Thus

a

group

delay

correction

to

the

upper

limit

frequency

of

the

oscilloscope

is

possible

with

the

aid

of

an

1

MHz

calibrator,

e.g.

HZ60.

In

fact

the

bandwidth

and

rise

time

of

the

oscilloscope

are

not

noticably

changed

with

these

probe

types

and

the

wave¬

form

reproduction

fidelity

can

even

be

improved

because

the

probe

can

be

matched

to

the

oscilloscope's

individual

pulse

response.

If

a

xIO

orxIOO

attenuator

probe

is

used,

DC

input

cou¬

pling

must

always

be

used

at

voltages

above

400

V.

With

AC

coupling

of

low

frequency

signals,

the

attenuation

is

no

longer

independent

of

frequency,

pulses

can

show

pulse

tilts.

Direct

voltages

are

suppressed

but

load

the

oscil¬

loscope

input

coupling

capacitor

concerned.

Its

voltage

rat¬

ing

is

max.

400

V

(DC

-F

peak

AC).

DC

input

coupling

is

therefore

of

quite

special

importance

with

a

xlOO

attenua¬

tion

probe

which

usually

has

a

voltage

rating

of

max.

1

200

V

(DC

+

peak

AC).

A

capacitor

of

corresponding

capaci¬

tance

and

voltage

rating

may

be

connected

in

series

with

the

attenuator

probe

input

for

blocking

DC

voltage

(e.g.

for

hum

voltage

measurement).

With

all

attenuator

probes,

the

maximum

AC

input

volt¬

age

must

be

derated

with

frequency

usually

above

20

kHz.

Therefore

the

derating

curve

of

the

attenuator

probe

type

concerned

must

be

taken

into

account.

The

selection

of

the

ground

point

on

the

test

object

is

impor¬

tant

when

displaying

small

signal

voltages.

It

should

always

be

as

close

as

possible

to

the

measuring

point.

If

this

is

not

done,

serious

signal

distortion

may

result

from

spurious

cur¬

rents

through

the

ground

leads

or

chassis

parts.

The

ground

leads

on

attenuator

probes

are

also

particularly

critical.

They

should

be

as

short

and

thick

as

possible.

When

the

attenuator

probe

is

connected

to

a

BNC-socket,

a

BNC-

adapter,

which

is

often

supplied

as

probe

accessory,

should

be

used.

In

this

way

ground

and

matching

problems

are

eliminated.

Hum

or

interference

appearing

in

the

measuring

circuit

(especially

when

a

small

deflection

coefficient

is

used)

is

possibly

caused

by

multiple

grounding

because

equalizing

M6

203-7

Subject

to

change

without

notice