Hameg CombiScope HM1508-2 User manual

Form 080/01
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150 MHz
Mixed Signal CombiScope®
HM1508-2
Manual
English

2Subject to change without notice
General information regarding the CE marking
HAMEG instruments fulfill the regulations of the EMC directive. The
conformity test made by HAMEG is based on the actual generic- and
product standards. In cases where different limit values are applicable,
HAMEG applies the severer standard. For emission the limits for
residential, commercial and light industry are applied. Regarding the
immunity (susceptibility) the limits for industrial environment have
been used.
The measuring- and data lines of the instrument have much influence
on emission and immunity and therefore on meeting the acceptance
limits. For different applications the lines and/or cables used may
be different. For measurement operation the following hints and
conditions regarding emission and immunity should be observed:
1. Data cables
For the connection between instrument interfaces and external devices,
(computer, printer etc.) sufficiently screened cables must be used.
Without a special instruction in the manual for a reduced cable length,
the maximum cable length of a dataline must be less than 3 meters and
not be used outside buildings. If an interface has several connectors
only one connector must have a connection to a cable.
Basically interconnections must have a double screening. For IEEE-bus
purposes the double screened cable HZ72 from HAMEG is suitable.
2. Signal cables
Basically test leads for signal interconnection between test point and
instrument should be as short as possible. Without instruction in the
manual for a shorter length, signal lines must be less than 3 meters
and not be used outside buildings.
Signal lines must screened (coaxial cable - RG58/U). A proper ground
connection is required. In combination with signal generators double
screened cables (RG223/U, RG214/U) must be used.
Die HAMEG Instruments GmbH bescheinigt die Konformität für das Produkt
The HAMEG Instruments GmbH herewith declares conformity of the product
HAMEG Instruments GmbH déclare la conformite du produit
Bezeichnung / Product name / Designation:
Oszilloskop
Oscilloscope
Oscilloscope
Typ / Type / Type: HM1508-2
mit / with / avec: HO720
Optionen / Options / Options: HO730, HO740
mit den folgenden Bestimmungen / with applicable regulations / avec les
directives suivantes
EMV Richtlinie 89/336/EWG ergänzt durch 91/263/EWG, 92/31/EWG
EMC Directive 89/336/EEC amended by 91/263/EWG, 92/31/EEC
Directive EMC 89/336/CEE amendée par 91/263/EWG, 92/31/CEE
Niederspannungsrichtlinie 73/23/EWG ergänzt durch 93/68/EWG
Low-Voltage Equipment Directive 73/23/EEC amended by 93/68/EEC
Directive des equipements basse tension 73/23/CEE amendée par 93/68/CEE
Angewendete harmonisierte Normen / Harmonized standards applied / Normes
harmonisées utilisées:
Sicherheit / Safety / Sécurité: EN 61010-1:2001 (IEC 61010-1:2001)
Überspannungskategorie / Overvoltage category / Catégorie de surtension: II
Verschmutzungsgrad / Degree of pollution / Degré de pollution: 2
Elektromagnetische Verträglichkeit / Electromagnetic compatibility /
Compatibilité électromagnétique
EN 61326-1/A1 Störaussendung / Radiation / Emission:
Tabelle / table / tableau 4; Klasse / Class / Classe B.
Störfestigkeit / Immunity / Imunitée: Tabelle / table / tableau A1.
EN 61000-3-2/A14 Oberschwingungsströme / Harmonic current emissions /
Émissions de courant harmonique:
Klasse / Class / Classe D.
EN 61000-3-3 Spannungsschwankungen u. Flicker / Voltage fluctuations and flicker /
Fluctuations de tension et du flicker.
Datum /Date /Date
01. 12. 2006
Unterschrift / Signature / Signatur
Manuel Roth
Manager
3. Influence on measuring instruments
Under the presence of strong high frequency electric or magnetic
fields, even with careful setup of the measuring equipment, influence
of such signals is unavoidable.
This will not cause damage or put the instrument out of operation. Small
deviations of the measuring value (reading) exceeding the instruments
specifications may result from such conditions in individual cases.
4. RF immunity of oscilloscopes.
4.1 Electromagnetic RF field
The influence of electric and magnetic RF fields may become visible
(e.g. RF superimposed), if the field intensity is high. In most cases
the coupling into the oscilloscope takes place via the device under
test, mains/line supply, test leads, control cables and/or radiation.
The device under test as well as the oscilloscope may be effected by
such fields.
Although the interior of the oscilloscope is screened by the cabinet,
direct radiation can occur via the CRT gap. As the bandwidth of
each amplifier stage is higher than the total –3dB bandwidth of the
oscilloscope, the influence of RF fields of even higher frequencies
may be noticeable.
4.2 Electrical fast transients / electrostatic discharge
Electrical fast transient signals (burst) may be coupled into the
oscilloscope directly via the mains/line supply, or indirectly via test
leads and/or control cables. Due to the high trigger and input sensitivity
of the oscilloscopes, such normally high signals may effect the trigger
unit and/or may become visible on the CRT, which is unavoidable.
These effects can also be caused by direct or indirect electrostatic
discharge.
HAMEG Instruments GmbH
Hersteller HAMEG Instruments GmbH KONFORMITÄTSERKLÄRUNG
Manufacturer Industriestraße 6 DECLARATION OF CONFORMITY
Fabricant D-63533 Mainhausen DECLARATION DE CONFORMITE
General information regarding the CE marking

3
Subject to change without notice
Contents
General information regarding the CE marking 2
150 MHz Mixed Signal CombiScope®HM1508-2 4
Specifications 5
Important hints 6
List of symbols used: 6
Positioning the instrument 6
Safety 6
Proper operation 6
CAT I 6
Environment of use. 6
Environmental conditions 7
Warranty and repair 7
Maintenance 7
Line voltage 7
Description of the controls 8
Basic signal measurement 10
Signals which can be measured 10
Amplitude of signals 10
Values of a sine wave signal 10
DC and ac components of an input signal 11
Timing relationships 11
Connection of signals 11
First time operation and initial adjustments 12
Trace rotation TR 12
Probe adjustment and use 12
1 kHz adjustment 12
1 MHz adjustment 13
Operating modes of the vertical amplifier 13
XY operation 14
Phase measurements with Lissajous figures 14
Measurement of phase differences in dual
channel Yt mode 14
Measurement of amplitude modulation 15
Triggering and time base 15
Automatic peak triggering (MODE menu) 15
Normal trigger mode (See menu MODE) 16
Slope selection (Menu FILTER) 16
Trigger coupling (Menu: FILTER) 16
Video (tv triggering) 16
Frame sync pulse triggering 17
Line sync pulse triggering 17
LINE trigger 17
Alternate trigger 17
External triggering 17
Indication of triggered operation (TRIG’D LED) 17
Hold-off time adjustment 17
Time base B (2nd time base). Delaying,
Delayed Sweep. Analog mode. 18
Alternate sweep 18
AUTOSET 19
Component tester 19
CombiScope 21
DSO Operation 22
DSO operating modes 22
Memory resolution 22
Memory depth 23
Horizontal resolution with X magnifier 23
Maximum signal frequency in DSO mode 23
Display of aliases 23
Vertical amplifier operating modes 23
Data transfer 23
HO710: RS-232 Interface, Remote control 24
Selection of Baud rate 24
Data transmission 24
Loading of new firmware 24
General information concerning MENU 25
Controls and Readout 26

4Subject to change without notice
HM1508-2
1 GSa/s Real Time Sampling, 10 GSa/s Random Sampling
1 MPts Memory per Channel, Memory oom up to 50,000:1
FFT for spectral analysis
4 Channels (2 analog, 2 logic inputs)
Deflection coefficients: 1 mV/cm – 20 V/cm,
Time Base: 50 s/cm – 5 ns/cm
8-Bit Low Noise Flash A/D Converters
Acquisition modes: Single, Refresh, Average, Envelope,
Roll, Peak-Detect
Front USB-Stick Connector for Screenshots
USB/RS-232, optional: IEEE-488, Ethernet/USB
Signal display: Yt, XY and FFT;
Interpolation: Sinx/x, Pulse, Dot Join (linear)
Frequency Analysis
with FFT
150 MHz Mixed Signal
CombiScope®with FFT
HM1508-2
HM1508 2
DSO mode: Signal portion
expanded with zoom
(burst in one line)
DSO mode:
4-channel display of 2 analog
and 2 logic signals

5
Subject to change without notice
150 MHz Mixed Signal CombiScope®HM1508-2
Valid at 23 °C after a 30 minute warm-up period
Vertical Deflection
Channels:
Analog: 2
Digital: 2 + 2 Logic Channels
Operating Modes:
Analog: CH 1 or CH 2 separate, DUAL (CH 1 and
CH 2 alternate or chopped), Addition
Digital: Analog Signal Channels CH 1 or CH 2
separate, DUAL (CH 1 and CH 2), Addition
Logic Signal Channels: CH 3 and CH 4
X in XY-Mode: CH 1
Invert: CH 1, CH 2
Bandwidth (-3 dB): 2 x 0 – 150 MHz
Rise time: ‹ 2.3 ns
Bandwith limiting (selectable):about 20 MHz (5 mV/cm – 20 V/cm)
Deflection Coefficients(CH 1,2):14 calibrated steps
1mV – 2 mV/cm (10 MHz) ± 5 % (0 – 10 MHz (-3 dB))
5 mV – 20 V/cm ± 3 % (1-2-5 sequence)
variable (uncalibrated): › 2.5 :1 to › 50 V/cm
Inputs CH 1, 2:
Input Impedance: 1 MΩ II 15 pF
Coupling: DC, AC, GND (ground)
Max. Input Voltage: 400 V (DC + peak AC)
Y Delay Line (analog): 70 ns
Measuring Circuits: Measuring Category I
Digital mode only:
Logic Channels: CH 3, CH 4
Select. switching thresholds: TTL, CMOS, ECL
User definable thresholds: 3
within the range: -2 V to +3 V
Analog mode only:
Auxiliary input: CH 4: 100 V (DC + peak AC)
Function (selectable): Extern Trigger, Z (unblank)
Coupling: AC, DC
Max. input voltage: 100 V (DC + peak AC)
Triggering
Analog and Digital Mode
Automatic (Peak to Peak):
Min. signal height: 5mm
Frequency range: 10 Hz – 250 MHz
Level control range: from Peak- to Peak+
Normal (without peak):
Min. signal height: 5mm
Frequency range: 0 – 250 MHz
Level control range: -10 cm to +10 cm
Operating modes: Slope/Video/Logic
Slope: positive, negative, both
Sources: CH 1, CH 2, alt. CH 1/2 (≥8 mm, analog
mode only), Line, Ext.
Coupling: AC: 10 Hz–250 MHz
DC: 0– 250 MHz
HF: 30 kHz–250 MHz
LF: 0–5kHz
Noise Rej. switchable
Video: pos./neg. Sync. Impulse
Standards: 525 Line/60 Hz Systems
625 Line/50 Hz Systems
Field: even/odd/both
Line: all/line number selectable
Source: CH 1, CH 2, Ext.
Indicator for trigger action: LED
External Trigger via: CH 4 (0.3 Vpp, 150 MHz)
Coupling: AC, DC
Max. input voltage: 100 V (DC +peak AC)
Digital mode:
Logic: AND/OR, TRUE/FALSE
Source: CH1 or 2, CH3 and CH4
State: X, H, L
Pre/Post Trigger: -100 % to +400% related to complete memory
Analog mode
2nd Trigger
Min. signal height: 5mm
Frequency range: 0 – 250 MHz
Coupling: DC
Level control range: -10 cm to +10 cm
Horizontal Deflection
Analog mode
Operating modes: A, ALT (alternating A/B), B
Time base A: 0.5 s/cm – 50 ns/cm (1-2-5 sequence)
Time base B: 20 ms/cm – 50 ns/cm (1-2-5 sequence)
Accuracy A and B: ±3%
X Magnification x10: to 5 ns/cm
Accuracy: ±5%
Variable time base A/B: cont. 1:2.5
Hold Off time: var. 1:10 LED-Indication
Bandwidth X-Amplifier: 0 – 3 MHz (-3 dB)
X Y phase shift ‹ 3°: ‹ 220 kHz
Digital mode
Time base range (1-2-5 sequence)
Refresh Mode: 20 ms/cm – 5 ns/cm
with Peak Detect: 20ms/cm – 2 ms/cm (min. Pulse Width 10 ns)
Roll Mode: 50 s/cm – 50 ms/cm
Accuracy time base
Time base: 50 ppm
Display: ±1%
MEMORY ZOOM: max. 50,000:1
Bandwidth X-Amplifier: 0 – 150 MHz (-3 dB)
XY phase shift ‹ 3°: ‹ 100 MHz
Digital Storage
Sampling rate (real time): Analog channels: 2 x 500 MSa/s, 1 GSa/s
interleaved; Logic Channels: 2 x 500 MSa/s
Acquisition (random sampling): 10 GSa/s
Bandwidth: 2 x 0 – 150 MHz (random)
Memory: 1 M-Samples per Channel
Operating modes: Refresh, Average, Envelope/
Roll: Free Run/Triggered, Peak-Detect
Resolution (vertical): 8 Bit (25 Pts/cm)
Resolution (horizontal):
Yt: 11 Bit (200 Pts/cm)
XY: 8 Bit (25 Pts /cm)
Interpolation: Sinx/x, Dot Join (linear), Pulse
Delay: 1 Million x 1/Sampling Rate to
4 Million x 1/Sampling Rate
Display refresh rate: max.170/s at 1 MPts
Display: Dots (acquired points only), Vectors (partly
interpolated), optimal (complete memory
weighting and vectors)
Reference Memories: 9 with 2 kPts each (for recorded signals)
Display: 2 signals of 9 (free selectable)
FFT Mode
Display X: Frequency Range
Disaplay Y: True rms value of spectrum
Scaling: Linear or logarithmic
Level display: dBV, V
Window: Square, Hanning, Hamming, Blackmann
Control: Center frequency, Span
Marker: Frequency, Amplitude
Zoom (frequency axis): up to x 20
Operation/Measuring/Interfaces
Operation: Menu (multilingual), Autoset,
help functions (multilingual)
Save/Recall (instrument parameter settings): 9
Signal display: max. 4 signals or 4 traces
analog: CH 1, 2 (Time Base A) in combination with
CH 1, 2 (Time Base B)
digital: CH 1, 2 and CH 3, 4 or ZOOM or Reference
or Mathematics
USB Memory-Stick:
Save/Recall external:
Instrument settings and Signals: CH 1, 2 and CH 3, 4 or ZOOM or
Reference or Mathematics
Screen-shot: as Bitmap
Signal display data (2k per channel): Binary (SCPI-Data), Text (ASCII-
Format), CSV (Spread Sheet)
Frequency counter:
6 digit resolution: › 1 MHz – 250 MHz
5 digit resolution: 0.5 Hz – 1 MHz
Accuracy: 50 ppm
Auto Measurements:
Analog mode: Frequency, Period, Vdc, Vpp, Vp+, Vp-
also in digital mode: Vrms, Vavg
Cursor Measurements:
Analog mode: Δt, 1/Δt (f), tr, ΔV, V to GND, ratio X, ratio Y
plus in digital mode: Vpp, Vp+, Vp-, Vavg, Vrms, pulse count
/
Specifications

6Subject to change without notice
Important hints
Please check the instrument for mechanical damage or loose
parts immediately after unpacking. In case of damage we advise
to contact the sender. Do not operate.
List of symbols used
Consult the manual High voltage
STOP
Important note Ground
Positioning the instrument
As can be seen from the figures, the handle can be set into
different positions:
A and B = carrying
C = horizontal operating
D and E = operating at different angles
F = handle removal
T = shipping (handle unlocked)
STOP
Attention!
When changing the handle position, the instrument
must be placed so that it can not fall (e.g. placed
on a table). Then the handle locking knobs must be
simultaneously pulled outwards and rotated to the
Important hints
A
A
B
B
C
C
D
D
E
E
T
F
PUkT
PUkT
PUk PUk PUk PUk PUk PUk
PUkT PUkT
PUkT
PUkT
PUkT
HGOPFFD
PUkT
HGOFFD
PUOPFGkT
PUkT
PUkTKl
15pF
max
400Vp
PUOPFGkT
PUOPFGkT
PUOPFGkT
PUOPFGkT
PGkT PUOPFGkT
PUOPFGkT PFGkT
PUOPFGkTPUOPFGkT
PUOPFGkT PUOPFGkT
PUOPFGkT
HAMEG
PUOPFGkT
PUOPFGkT
PUOPFGkT
ANALOG
DIGITAL
MIXED SIGNAL
COMBISCOPE
HM1508
1 GSa · 1MB
150 MHz
PUOGkT
VOLTS/DIVV
HGOPFFD
VOLTS/DIVV
HGOPFFD
VOLTS/DIVV
HGOPFFD
PUkT
HGOPFFD
PUkT
HGOPFFD
PUkT
PUkT
PUkT
PUkT
PUkT
PUkT PUkT
PUkTKl
15pF
max
400Vp
PUOPFGkT
INPUTS
PUOPF
PUOPF
PUOPF
PUOPF PUOPF
C O M B I S C O P E
B
T
T
required position. Without pulling the locking knobs
they will latch in into the next locking position.
Handle mounting/dismounting
The handle can be removed by pulling it out further, depending
on the instrument model in position B or F.
Safety
The instrument fulfils the VDE 0411 part 1 regulations for
electrical measuring, control and laboratory instruments and
was manufactured and tested accordingly. It left the factory in
perfect safe condition. Hence it also corresponds to European
Standard EN 61010-1 resp. International Standard IEC 1010-1.
In order to maintain this condition and to ensure safe operation
the user is required to observe the warnings and other directions
for use in this manual. Housing, chassis as well as all measu-
ring terminals are connected to safety ground of the mains.
All accessible metal parts were tested against the mains with
2200 VDC. The instrument conforms to safety class I.
The oscilloscope may only be operated from mains outlets with
a safety ground connector. The plug has to be installed prior to
connecting any signals. It is prohibited to separate the safety
ground connection.
Most electron tubes generate X-rays; the ion dose rate of this in-
strument remains well below the 36 pA/kg permitted by law.
Accessories supplied: Line cord, Operating manual, 4 Probes 10:1 with
attenuation ID (HZ200), Windows Software for control and data transfer
Optional accessories:
HO730 Dual-Interface Ethernet/USB,
HO740 Interface IEEE-488 (GPIB),
HZ70 Opto-Interface (with optical fiber cable)
pp p p g
Resolution Readout/Cursor: 1000 x 2000 Pts, Signals: 250 x 2000
Interfaces (plug-in): USB/RS-232 (HO720)
Optional: IEEE-488, Ethernet/USB
Mathematic functions
Number of Formula Sets: 5 with 5 formulas each
Sources: CH 1, CH 2, Math 1–Math 5
Targets: 5 math. memories, Math 1–5
Functions: ADD, SUB, 1/X, ABS, MUL, DIV, SQ, POS, NEG, INV
Display: max. 2 math. memories (Math 1–5)
Display
CRT: D14-375GH
Display area (with graticule): 8 cm x 10 cm
Acceleration voltage: approx. 14 kV
General Information
Component tester
Test voltage: approx. 7 Vrms (open circuit), approx. 50 Hz
Test current: max. 7 mArms (short circuit)
Reference Potential : Ground (safety earth)
Probe ADJ Output: 1 kHz/1 MHz square wave signal 0.2 Vpp (tr ‹ 4 ns
Trace rotation: electronic
Line voltage: 105 – 253 V, 50/60 Hz ±10 %, CAT II
Power consumption: 47 Watt at 230V, 50 Hz
Protective system: Safety class I (EN61010-1)
Weight: 5.6 kg
Cabinet (W x H x D): 285 x 125 x 380 mm
Ambient temperature: 0 °C ...+40 °C

7
Subject to change without notice
Type of fuse:
Size 5 x 20 mm; 250V~, C;
IEC 127, Bl. III; DIN 41 662
(or DIN 41 571, Bl. 3).
Cut off: slow blow (T) 0,8A.
Important hints
In case safe operation may not be guaranteed do not use the
instrument any more and lock it away in a secure place.
Safe operation may be endangered if any of the following
was noticed:
– in case of visible damage.
– in case loose parts were noticed
– if it does not function any more.
– after prolonged storage under unfavourable conditions (e.g.
like in the open or in moist atmosphere).
– after any improper transport (e.g. insufficient packing not
conforming to the minimum standards of post, rail or trans-
port firm)
Proper operation
Please note: This instrument is only destined for use by person-
nel well instructed and familiar with the dangers of electrical
measurements.For safety reasons the oscilloscope may only
be operated from mains outlets with safety ground connector.
It is prohibited to separate the safety ground connection. The
plug must be inserted prior to connecting any signals.
CAT I
This oscilloscope is destined for measurements in circuits not
connected to the mains or only indirectly. Direct measurements,
i.e. with a galvanic connection to circuits corresponding to the
categories II, III, or IV are prohibited!
The measuring circuits are considered not connected to the
mains if a suitable isolation transformer fulfilling safety class
II is used. Measurements on the mains are also possible if
suitable probes like current probes are used which fulfil the
safety class II. The measurement category of such probes must
be checked and observed.
Measurement categories
The measurement categories were derived corresponding to
the distance from the power station and the transients to be
expected hence. Transients are short, very fast voltage or cur-
rent excursions which may be periodic or not.
Measurement CAT IV:
Measurements close to the power station, e.g. on electricity
meters
Measurement CAT III:
Measurements in the interior of buildings (power distribution
installations, mains outlets, motors which are permanently
installed).
Measurement CAT II:
Measurements in circuits directly connected to the mains
(household appliances, power tools etc).
Measurement CAT I:
Electronic instruments and circuits which contain circuit
breakers resp. fuses.
Environmental conditions
The oscilloscope is destined for operation in industrial, business,
manufacturing, and living sites.
Operating ambient temperature: 0 to + 40 degrees C. During
transport or storage the temperature may be –20 to +55 degrees
C. Please note that after exposure to such temperatures or in
case of condensation proper time must be allowed until the
instrument has reached the permissible range of 0 to + 40 de-
grees resp. until the condensation has evaporated before it may
be turned on! Ordinarily this will be the case after 2 hours. The
oscilloscope is destined for use in clean and dry environments.
Do not operate in dusty or chemically aggressive atmosphere
or if there is danger of explosion.
The operating position may be any, however, sufficient ventila-
tion must be ensured (convection cooling). Prolonged operation
requires the horizontal or inclined position.
STOP
Do not obstruct the ventilation holes!
Specifications are valid after a 20 minute warm-up period
between 15 and 30 degr. C. Specifications without tolerances
are average values.
Warranty and repair
HAMEG instruments are subjected to a strict quality control.
Prior to leaving the factory, each instrument is burnt-in for 10
hours. By intermittent operation during this period almost all
defects are detected. Following the burn-in, each instrument is
tested for function and quality, the specifications are checked
in all operating modes; the test gear is calibrated to national
standards.
The warranty standards applicable are those of the country
in which the instrument was sold. Reclamations should be
directed to the dealer.
Only valid in EU countries
In order to speed reclamations customers in EU countries may
also contact HAMEG directly. Also, after the warranty expired,
the HAMEG service will be at your disposal for any repairs.
Return material authorization (RMA):
Prior to returning an instrument to HAMEG ask for a RMA
number either by internet (http://www.hameg.com) or fax. If
you do not have an original shipping carton, you may obtain
one by calling the HAMEG sales dept ([phone]) or by
sending an email to [email protected].
Maintenance
Clean the outer shell using a dust brush in regular intervals.
Dirt can be removed from housing, handle, all metal and plastic
parts using a cloth moistened with water and 1 % detergent.
Greasy dirt may be removed with benzene (petroleum ether) or
alcohol, there after wipe the surfaces with a dry cloth. Plastic
parts should be treated with an antistatic solution destined
for such parts. No fluid may enter the instrument. Do not use
other cleansing agents as they may adversely affect the plastic
or lacquered surfaces.
Line voltage
The instrument has a wide range power supply from 105 to 253
V, 50 or 60 Hz ±10%. There is hence no line voltage selector.
The line fuse is accessible on the rear panel and part of the line
input connector. Prior to exchanging a fuse the line cord must
be pulled out. Exchange is only allowed if the fuse holder is
undamaged, it can be taken out using a screwdriver put into the
slot. The fuse can be pushed out of its holder and exchanged.
The holder with the new fuse can then be pushed back in place
against the spring. It is prohibited to ”repair“ blown fuses or to
bridge the fuse. Any damages incurred by such measures will

8Subject to change without notice
Front Panel Elements – Brief Description
Front Panel Elements – Brief Description
1
POWER (pushbutton) 26
Turns scope on and off.
2
INTENS (knob) 26
Intensity for trace- and readout brightness, focus and trace
rotation control.
3
FOCUS/TRACE/MENU (pushbutton) 26
Calls the Intensity Knob menu to be displayed and enables
the change of different settings using the INTENS knob. See
item 2.
4
CURSOR MEASURE (pushbutton) 26
Calls the ”Cursor” menu and offers measurement selection
and activation.
5
ANALOG/DIGITAL (pushbutton) 27
Switches between analog (green) and digital mode (blue).
6
RUN/STOP (pushbutton) 28
RUN: Signal data acquisition enabled.
STOP (constantly lit): Signal data acquisition is stopped
STOP (flashing): Signal data acquisition is in progress and
flashing stops when completed.
7
MATH (pushbutton) 28
Calls mathematical function menu if digital mode is pre-
sent.
8
ACQUIRE (pushbutton) 29
Calls the signal capture and display mode menu in digital
mode.
9
SAVE/RECALL (pushbutton) 30
Offers access to the reference signal (digital mode only) and
the instrument settings memory.
10
SETTINGS (pushbutton) 31
Opens menu for language and miscellaneous function; in
digital mode also signal display mode.
11
AUTOSET (pushbutton) 32
Enables appropriate, signal related, automatic instrument
settings.
12
HELP (pushbutton) 32
Switches help texts regarding controls and menus on and
off.
13
POSITION 1 (knob) 32
Controls position of actual present functions: Signal (current,
reference or mathematics), Cursor and ZOOM (digital).
14
POSITION 2 (knob) 33
Controls position of actual present functions: Signal (current,
reference or mathematics) Cursor and ZOOM (digital).
15
CH1/2-CURSOR-CH3/4-MA/REF-ZOOM (pushbutton) 34
Calls the menu and indicates the current function of POSI-
TION 1 and 2 controls.
16
VOLTS/DIV-SCALE-VAR (knob) 34
Channel 1 Y deflection coefficient, Y variabel and Y scaling
setting.
17
VOLTS/DIV-SCALE-VAR (knob) 34
Channel 2 Y deflection coefficient, Y variabel and Y scaling
setting.
18
AUTO MEASURE (pushbutton) 35
Calls menus and submenus for automatic measurement.
19
LEVEL A/B - FFT-Marker (knob) 36
Trigger level control for A- and B Time Base. Marker position
shift in FFT mode.
20
MODE (pushbutton) 36
Calls selectable trigger modes.
21
FILTER (pushbutton) 37
Calls selectable trigger filter (coupling), noise reject and
slope selection.
22
SOURCE (pushbutton) 38
Calls trigger source menu (e.g. CH1, CH2, Alt. 1/2, External,
AC Line).
23
TRIG’d (LED) 38
Lit when the trigger signal meets the trigger conditions.
24
NORM (LED) 38
Lit if NORMAL or SINGLE event triggering is chosen.
25
HOLD OFF (LED) 38
Lit if a hold off time is set (only in analog mode) >0% in the
HOR menu (HOR/VAR pushbutton
30
).
26
X-POS / DELAY (pushbutton) 39
Calls and indicates (colour) the actual function of the
HORIZONTAL knob
27
, (X-POS dark).
27
HORIZONTAL (knob) 39
Changes the X position or in digital mode, the delay time (Pre-
/Post-Trigger). In FFT mode for center frequency control.
28
TIME/DIV-SCALE-VAR (knob) 39
Setting of A and B time base (deflection coefficient), time
fine control (VAR; analog mode only) and scaling; Span in
FFT mode.
29
MAG x10 (pushbutton) 41
10 fold expansion in X direction in analog Yt mode, with
simultaneous change of the deflection coefficient display
in the readout.
30
HOR / VAR (pushbutton) 41
Calls ZOOM function (digital) and analog mode time base A
and B, time base variable and hold off control.
31
CH1 / VAR (pushbutton) 42
Calls channel 1 menu with input coupling (AC, DC, GND),
inverting, probe and Y variable control.
32
VERT/XY (pushbutton) 43
Calls vertical mode selection, addition, XY mode and band-
width limiter.
33
CH2 / VAR (pushbutton) 44
Calls channel 1 menu with input coupling (AC, DC, GND),
inverting, probe and Y variable control.
34
INPUT CH1 (BNC socket) 45
Channel 1 signal input and input for horizontal deflection in
XY mode.
The figures indicate the page for complete discription
in the chapter CONTROLS AND READOUT ▼

9
Subject to change without notice
Front Panel Elements – Brief Description
35
INPUT CH2 (BNC socket) 45
Channel 2 signal input.
36
CH3/4 (pushbutton) 45
Digital mode: Logic signal channels 3 and 4. On condition
OFF, CH4 becomes the external trigger input.
Analog mode: CH4 can be used for intensity modulation (Z)
if external triggering is switched off.
37
FFT (pushbutton) 46
Calls FFT menu, offers window and scaling selection, as well
as function switch off. Calls FFT menu if FFT mode is present.
Direct switch over from digital Yt mode to FFT mode.
38
CH3 LOGIC INPUT (BNC socket) 47
Input for logic signals in digital mode.
39
CH4 LOGIC INPUT (BNC-socket) 47
Digital mode: Input for logic signals or external trigger
signals. Analog mode: Input for intensity modulation (Z) or
external trigger signals.
40
PROBE / ADJ (socket) 47
Square wave signal output for frequency compensation of
x10 probes.
41
PROBE / ADJ (pushbutton) 47
Calls menu that offers COMPONENT Tester operation, fre-
quency selection of PROBE ADJ square wave signal, hard-
ware and software information and details about interface
(rear side) and “USB Stick“ (flash drive) connector.
42
COMPONENT TESTER (2 sockets with 4 mm Ø) 48
Connectors for test leads of the Component Tester. Left
socket is galvanically connected with protective earth.
43
USB Stick (USB flash drive connector; front side) 48
Enables storage and load of signals and signal parameters
in connection with USB flash drives.
44
MENU OFF (pushbutton) 48
Switches the menu display off or one step back in the menu
hierarchy.
VA R VA R VA R x10
FFT-
Marker
POSITION 1 POSITION 2 HORIZONTAL
CH 3 CH 4
MATH
SAVE/
RECALL AUTOSET
ACQUIRE SETTINGS HELP
CH 1/2
VOLTS / DIV
SCALE ·VAR
VOLTS / DIV
SCALE ·VAR
TIME / DIV
SCALE ·VAR
20V 1 mV 20V 1 mV
X-POS
INPUTS
1MΩII15pF
max
400 Vp
X-INP
LOGIC
INPUTS
1MΩII15pF
max
100 Vp
INTENS
!
TRIGGER
LEVEL A/B
HM1508-2
ANALOG
DIGITAL
MIXED SIGNAL
OSCILLOSCOPE
1 GSa ·1 MB
150 MHz
50s 5ns
CURSOR
DIGITAL
ANALOG
DELAY
CH 3/4
MA/REF
ZOOM
FOCUS
TRACE
MENU
CAT I
!
CAT I
!
MODE
FILTER
SOURCE
TRIG’d
NORM
HOLD OFF
VERT/XY CH 3/4
CURSOR
MEASURE
FFT
RUN / STOP
CH 1 CH 2
TRIG. EXT. / Z-INP.
CH 1 CH 2 HOR MAG
AUTO
MEASURE
POWER
POWER
MENU
MENU
OFF
OFF
13
44
19
121110
1 2 3 4 5 6 7 8 9
15
14
17
16
18
31 34 32 33 35 36 38 37 39
26
27
24
23
21
24
28
22
25
29
30
COMBISCOPE
USB
Stick
COMP.
TESTER
PROBE
ADJ
POWER
MENUMENU
OFF
OFF
43 42 41 40 44

10 Subject to change without notice
Basic signal measurement
Signals which can be measured
The following description pertains to analog and digital ope-
ration. The different specifications in both operating modes
should be kept in mind.
The oscilloscope HM1508-2 can display all repetitive signals
with a fundamental repetition frequency of at least 150MHz.
The frequency response is 0 to 150MHz (-3 dB). The vertical
amplifiers will not distort signals by overshoots, undershoots,
ringing etc.
Simple electrical signals like sine waves from line frequency
ripple to hf will be displayed without problems. However, when
measuring sine waves, the amplitudes will be displayed with an
error increasing with frequency. At 100MHz the amplitude error
will be around –10 %. As the bandwidths of individual instru-
ments will show a certain spread (the 150MHz is a guaranteed
minimum) the actual measurement error for sine waves cannot
be exactly determined.
Pulse signals contain harmonics of their fundamental fre-
quency which must be represented, so the maximum useful
repetition frequency of non sinusoidal signals is much lower
than 150 MHz (5 to 10 times). The criterion is the relationship
between the rise times of the signal and the scope; the scope’s
rise time should be <1/3 of the signal’s rise time if a faithful
reproduction without too much rounding of the signal shape
is to be preserved.
The display of a mixture of signals is especially difficult if it
contains no single frequency with a higher amplitude as the
scope’s trigger system normally discriminates by amplitude.
This is typical of burst signals for example. Display of such
signals may require using the HOLD OFF control.
Composite video signals may be displayed easily as the instru-
ment has a tv sync separator.
The maximum sweep speed of 5 ns/cm allows sufficient time
resolution, e.g. a 100MHz sine wave will be displayed one period
per 2 cm.
The vertical amplifier inputs may be DC or AC coupled. Use DC
coupling only if necessary and preferably with a probe.
Low frequency signals when AC coupled will show tilt (AC low
frequency – 3 dB point is 1.6 Hz), so if possible use DC coupling.
Using a probe with 10:1 or higher attenuation will lower the
–3 dB point by the probe factor. If a probe cannot be used due
to the loss of sensitivity, DC coupling the scope and an external
large capacitor may help which, of course, must have a sufficient
DC rating. Care must be taken, however, when charging and
discharging a large capacitor.
DC coupling is preferable with all signals of varying duty cycle,
otherwise the display will move up and down depending on the
duty cycle. Of course, pure DC can only be measured with DC
coupling.
The readout will show which coupling was chosen: = stands for
DC, ~ stands for AC.
Amplitude of signals
In contrast to the general use of rms values in electrical engi-
neering oscilloscopes are calibrated in Vpp as that is what is
displayed.
To derive rms from Vpp: divide by 2.84. To derive Vpp from rms:
multiply by 2.84.
Values of a sine wave signal
Vrms = rms value
Vpp = pp – value
Vmom = momentary value, depends on time vs. period.
The minimum signal for a one cm display is 1 mVpp ±5 % provi-
ded 1 mV/cm was selected and the variable is in the calibrated
position.
The available sensitivities are given in mVpp or Vpp. The cursors
let you read the amplitudes of the signals immediately on the
readout as the attenuation of probes is automatically taken into
account. Even if the probe attenuation was selected manually
this will be overridden if the scope identifies a probe with an
identification contact as different. The readout will always give
the true amplitude.
It is important that the variable be in its calibrated position.
The sensitivity may be continuously decreased by using the
variable (see Controls and Readout). Each intermediate value
between the calibrated positions 1–2–5 may be selected. Thus
a maximum of 400 Vpp may be displayed without using a probe
(20 V/div x 8 cm screen x 2.5 variable).
Amplitudes may be directly read off the screen by measuring
the height and multiplying by the V/div. setting.
STOP
Please note: Without a probe the maximum permis-
sible voltage at the inputs must not exceed 400 Vp
irrespective of polarity.
In case of signals with a DC content the peak value DC + AC
peak must not exceed + or – 400 Vp. Pure AC of up to 800 Vpp
is permissible.
STOP
If probes are used their possibly higher ratings are
only usable if the scope is DC coupled.
In case of measuring DC with a probe while the scope input is
AC coupled the capacitor in the scope input will see the input
DC voltage as it is in series with the internal 1 MΩ resistor.
This means that the maximum DC voltage (or DC + peak AC) is
that of the scope input, i.e. 400 VP! With signals which contain
DC and AC the DC content will stress the input capacitor while
the AC content will be divided depending on the AC impedance
Basic signal measurement
VpVrms
Vmom
Vpp

11
Subject to change without notice
of the capacitor. It may be assumed that this is negligible for
frequencies >40 Hz.
Considering the foregoing you may measure DC signals of
up to 400 V or pure AC signals of up to 800 Vpp with a HZ200
probe. Probes with higher attenuation like HZ53 100:1 allow
you to measure DC up to 1200 V and pure AC of up to 2400 Vpp.
(Please note the derating for higher frequencies, consult the
HZ53 manual). Stressing a 10:1 probe beyond its ratings will
risk destruction of the capacitor bridging the input resistor with
possible ensuing damage of the scope input!
If the residual ripple of a high voltage is to be measured, a high
voltage capacitor may be inserted in front of a 10:1 probe, it will
take most of the voltage as the value of the probe’s internal
capacitor is very low, 22 to 68 nF will be sufficient.
If the input selector is switched to Ground the reference trace
on the screen may be positioned at graticule center or else-
where.
DC and AC components of an input signal
The dashed curve shows an AC signal symmetrical about zero. If
there is a DC component the peak value will be DC + AC peak.
Timing relationships
In most cases repetitive signals must be measured. The repe-
tition frequency of a signal is equal to the number of periods
per second. Depending on the TIME/DIV setting one or more
periods or part of a period of the signal may be displayed. The
time base settings will be indicated on the readout in s/cm,
ms/cm, μs/cm and ns/cm (1 cm is the equivalent of 1 div. on
the crt graticule). Also the cursors may be used to measure the
frequency or the period.
Without cursor the cycle duration can be determined by multi-
plying the length (cm) with the (calibrated) time coefficient. The
reciprocal value is the frequency.
If portions of the signal are to be measured use delayed sweep
(analog mode) or zoom (digital mode) or the magnifier x10. Use
the HORIZONTAL positioning control to shift the portion to be
zoomed into the screen center.
Pulse signals are characterized by their rise and fall times
which are measured between the 10 % and 90 % portions. The
following example uses the internal graticule of the crt, but also
the cursors may be used for measurement.
Measurement:
– Adjust the rising portion of the signal to 5 cm.
– Position the rising portion symmetrically to the graticule
centre line, using both Y and X positioning controls.
– Notice the intersections of the signal with the 10 and 90 %
lines and project these points to the centre line in order to
read the time difference.
In the example it was 1.6 cm at 5 ns/cm equals 8 ns rise time.
When measuring very short rise times coming close to the scope
rise time it is necessary to subtract the scope’s (and if used the
probe’s) rise times geometrically from the rise time as seen on
the screen. The true signal rise time will become:
ttot is the rise time seen, tosc is the scope’s own rise time (2.3
ns with the HM1508-2), ttis the rise time of the probe, e.g. 2 ns.
If the signal’s rise time is >22 ns, the rise times of scope and
probe may be neglected.
For the measurement of rise times proceed mainly as outlined
above, however rise times may be measured anywhere on the
screen. It is mandatory that the rising portion of the signal be
measured in full and that the 10 to 90 % are observed. In case of
signals with over or undershoot, the 0 and 100 % levels are those
of the horizontal portions of the signal, i.e. the over/undershoot
must be disregarded for rise and fall time measurements. Also,
glitches should be disregarded. If signals are very distorted, ho-
wever, rise and fall time measurements may be of no value.
For most amplifiers, even if their pulse behaviour is far from
ideal, the following relationship holds:
350 350
ta=
—— B = ——
B ta
tr/ns = 350/Bandwidth/MHz
Connection of signals
In most cases pressing the AUTOSET button will yield a satisf-
actory display (see AUTOSET). The following relates to special
cases where manual settings will be advisable. For a description
of controls refer to ”Controls and Readout“.
STOP
Take care when connecting unknown signals to the
inputs!
It is recommended to use probes whenever possible. Without
a probe start with the attenuator set to its 20 V/cm position. If
the trace disappears the signal amplitude may be too large,
overdriving the vertical amplifier and/or its DC content may be
too high. Reduce the sensitivity until the trace will reappears
on screen. If calibrated measurements are desired it will be
necessary to use a probe if the signal becomes >160 Vp. Check
the probe specifications in order to avoid overstressing. If the
time base is set too fast the trace may become invisible, then
reduce the time base speed.
Basic signal measurement
ta= 82- 2.32- 22= 7,4ns
ta= ttot2– tosc2– tt2
voltage
peak
AC
DC
DC
AC
DC + ACpeak = 400Vmax
5 cm
ttot
100%
90%
10%
0%

12 Subject to change without notice
If no probe is used at least screened cable should be used,
such as HZ32 or HZ34. However, this is only advisable for low
impedance sources or low frequencies (<50 kHz). With high
frequencies impedance matching will be necessary.
Nonsinusoidal signals require impedance matching, at both
ends preferably. At the scope input a feed through 50Ω-termi-
nation will be required. HAMEG offers a HZ22 termination. If
proper terminations are not used, sizeable pulse aberrations
will result. Also sine wave signals of >100 kHz should be pro-
perly terminated. Most generators control signal amplitudes
only if correctly terminated.
HZ22 may only be used up to 7 Vrms or 20 Vpp i.e. 1 W.
For probes, terminations are neither required nor allowed, they
would ruin the signal.
Probes feature very low loads at fairly low frequencies: 10 MΩ
in parallel with few pF, valid up to several hundred kHz. How-
ever, the input impedance diminishes with rising frequency to
quite low values. This has to be borne in mind as probes are,
e.g., entirely unsuitable to measure signals across high impe-
dance high frequency circuits such as bandfilters etc.! Here
only FET probes can be used. Use of a probe as a rule will also
protect the scope input due to the high probe series resistance
(9MΩ). As probes cannot be calibrated precisely enough during
manufacturing, individual calibration with the scope input used
is mandatory! (See Probe Calibration).
Passive probes will, as a rule, decrease the scope bandwidth and
increase the rise time. We recommend to use HZ200 probes in
order to make maximum use of the combined bandwidth. HZ200
features 2 additional hf compensation adjustments.
Whenever the DC content is >400 V, DC coupling must be used
in order to prevent overstressing the scope input capacitor.
This is especially important if a 100:1 probe is used as this is
specified for 1200 VDC + peak AC.
AC coupling of low frequency signals may produce tilt.
If the DC content of a signal must be blocked, it is possible to
insert a capacitor of proper size and voltage rating in front of the
probe, a typical application would be a ripple measurement.
When measuring small voltages the selection of the ground
connection is of vital importance. It should be as close to voltage
take off point as possible, otherwise ground currents may de-
teriorate the measurement. The ground connections of probes
are especially critical, they should be as short as possible and
of large diameter.
STOP
If a probe is to be connected to a BNC connector use
a probe tip to BNC adapter.
If ripple or other interference is visible, especially at high sen-
sitivity, one possible reason may be multiple grounding. The
scope itself and most other equipment are connected to safety
ground, so ground loops may exist. Also, most instruments will
have capacitors between line and safety ground installed, which
conduct current from the live wire into the safety ground.
First time operation and initial adjustments
Prior to first time operation the connection between the instru-
ment and safety ground must be ensured, hence the plug must
be inserted first.
Use the red POWER pushbutton to turn the scope on. Several
displays will light up. The scope will then assume the set up,
which was selected before it was turned off. If no trace and
no readout are visible after approximately 20 sec, push the
AUTOSET button.
As soon as the trace becomes visible select an average inten-
sity with INTENS, then select FOCUS and adjust it, then select
TRACE ROTATION and adjust for a horizontal trace.
With respect to crt life, use only as much intensity as necessary
and convenient under given ambient light conditions. When not
in use, turn the intensity fully off rather than switching the scope
on and off too much as this is detrimental to the life of the crt
heater. Do not allow a stationary point on the screen, it might
burn the crt phosphor.
With unknown signals start with the lowest sensitivity 20 V/cm,
connect the input cables to the scope, and then to the measuring
object which should be de energized beforehand. Then turn the
measuring object on. If the trace disappears, push AUTOSET.
Trace rotation TR
The crt has an internal graticule. In order to adjust the deflected
beam with respect to this graticule the Trace Rotation control
is provided. Select the function Trace Rotation and adjust for a
trace which is exactly parallel to the graticule.
Probe adjustment and use
In order to ensure proper matching of the probe used to the
scope input impedance the oscilloscope contains a calibrator
with short rise time and an amplitude of 0.2 Vpp ± 1 %, equivalent
to 4 cm at 5 mV/cm when using 10:1 probes.
The inner diameter of the calibrator connector is 4.9 mm and
standardized for series F probes. Using this special connec-
tor is the only way to connect a probe to a fast signal source
minimizing signal and ground lead lengths and to ensure true
displays of pulse signals.
1 kHz – adjustment
This basic adjustment will ensure that the capacitive at-
tenuation equals the resistive attenuation thus rendering the
attenuation of the probe independent of frequency. 1:1 probes
can not be adjusted and need no such adjustment anyway.
Prior to adjustment make sure that the trace rotation adjust-
ment has been performed.
First time operation and initial adjustments
incorrect correct incorrect

13
Subject to change without notice
Operating modes of the vertical amplifier
The controls most important for the vertical amplifier are: VERT/
XY
32
, CH1
31
, CH2
33
– and in digital mode also – CH3/4
36
.
They give access to the menus containing the operating modes
and the parameters of the individual channels.
Changing the operating mode is described in the chapter:
”Controls and Readout“.
Remark: Any reference to ”both channels“ always refers to
channels 1 and 2.
Usually oscilloscopes are used in the Yt mode. In analog mode
the amplitude of the measuring signal will deflect the trace
vertically while a time base will deflect it from left to right.
The vertical amplifiers offer these modes:
– One signal only with CH1.
– One signal only with CH2.
– Two signals with channels 1 and 2 (DUAL trace mode)
In DIGITAL mode the channels 3 and 4 are also available, but
for logic signals only.
In DUAL mode both channels are operative. In analog mode
the method of signal display is governed by the time base (see
also ”Controls and Readout“). Channel switching may either
take place after each sweep (alternate) or during sweeps at
high frequency (chopped).
The normal choice is alternate, however, at slow time base set-
tings the channel switching will become visible and disturbing,
when this occurs select the chopped mode in order to achieve
a stable quiet display.
In DIGITAL mode no channel switching is necessary as each
input has its own A/D converter, signal acquisition is simul-
taneous.
In ADD mode the two channels 1 and 2 are algebraically ad-
ded (±CH1 ±CH2). With +polarity the channel is normal, with
–polarity inverted. If +CH1 and –CH2 are selected the difference
will be displayed or vice versa.
Same polarity input signals:
Both channels not inverted: = sum
Both channels inverted: = sum
Only one channel inverted: = difference
Opposite polarity input signals:
Both channels not inverted: = difference
Both channels inverted: = difference
One channel inverted: = sum.
Please note that in ADD mode both position controls will be
operative. The INVERT function will not affect positioning.
Often the difference of two signals is to be measured at signal
points which are both at a high common mode (CM) potential.
While this one typical application of the difference mode one
important precaution has to be borne in mind: The oscilloscope
vertical amplifiers are two separate amplifiers and do not con-
stitute a true difference amplifier with both a high CM rejection
and a high permissible CM range! Therefore please observe the
following rule: Always look at the two signals in the one channel
only or the dual modes (not in Add mode) and make sure that
Connect the 10:1 probe to the input. Use DC coupling. Set
the VOLTS/DIV to 5 mV/cm and TIME/DIV to 0.2 ms/cm, both
calibrated. Insert the probe tip into the calibrator connector
PROBE ADJ.
You should see 2 signal periods. Adjust the compensation ca-
pacitor (see the probe manual for the location) until the square
wave tops are exactly parallel to the graticule lines (see picture
1 kHz). The signal height should be 4 cm ±1.6 mm (3% oscillo-
scope and 1% probe tolerance). The rising and falling portions
of the square wave will be invisible.
1 MHz adjustment
The HAMEG probes feature additional adjustments in the
compensation box which allow you to optimise their hf be-
haviour. This adjustment is a precondition for achieving the
maximum bandwidth with the probe and a minimum of pulse
aberrations.
This adjustment requires a calibrator with a short rise time
(typ. 4 ns) and a 50Ω output, a frequency of 1 MHz, an amplitude
of 0.2 Vpp. The PROBE ADJ. output of the scope fulfils these
requirements.
Connect the probe to the scope input with which it is to be adju-
sted. Select the PROBE ADJ. signal 1 MHz. Select DC coupling and
5mV/cm with VOLTS/DIV. and 0.1 μs/cm with TIME/DIV., both
calibrated. Insert the probe tip into the calibrator output con-
nector. The screen should show the signal, and the rise and
fall times will be visible. Watch the rising portion and the top
left pulse corner, consult the manual for the location of the
adjustments.
The criteria for a correct adjustment are:
– short rise time, steep slope.
– clean top left corner with minimum over or undershoot, flat
top.
After adjustment check the amplitude which should be the
same as with 1 kHz.
It is important to first adjust 1 kHz, then 1 MHz. It may be ne-
cessary to check the 1 kHz adjustment again.
Please note that the frequency of the calibrator signals is not
calibrated and thus must not be used to check the time base
accuracy, also the duty cycle may differ from 1:1.The probe
adjustment is completed if the pulse tops are horizontal and
the amplitude calibration is correct.
Operating modes of the vertical amplifier
incorrect correct incorrect

14 Subject to change without notice
they are within the permissible input signal range; this is the
case if they can be displayed in these modes. Only then switch
to ADD. If this precaution is disregarded grossly false displays
may result as the input range of one or both amplifiers may
be exceeded.
Another precondition for obtaining true displays is the use of
two identical probes at both inputs. But note that normal probe
tolerances (percent) will cause the CM rejection to be expected
to be rather moderate. In order to obtain the best possible re-
sults proceed as follows: First adjust both probes as carefully
as possible, then in Add mode select the same sensitivity at
both inputs and connect both probes to the output of a pulse
generator with sufficient amplitude to yield a good display. Re-
adjust one (!) of the probe adjustment capacitors for a minimum
of over or undershoot. As there is no adjustment provided with
which the resistors can be matched a residual pulse signal will
be unavoidable. When making difference measurements it is
good practice to first connect the ground cables of the probes
to the object prior to connecting the probe tips. There may be
high potentials between the object and the scope. If a probe tip
is connected first there is danger of overstressing the probe or/
and the scope inputs! Never perform difference measurements
without both probe ground cables connected.
XY operation
This mode is accessed by VERT/XY
32
>XY. In analog mode the
timebase will be turned off. The channel 1 signal will deflect in X
direction (X INP. = horizontal input), hence the input attenuators,
the variable and the POSITION 1 control will be operative. The
HORIZONTAL control will also remain functional.
Channel 2 will deflect in Y direction.
The x10 magnifier will be inoperative in XY mode. Please note the
differences in the Y and X bandwidths, the X amplifier has a lower
–3 dB frequency than the Y amplifier. Consequently the phase
difference between X and Y will increase with frequency.
In XY mode the X signal (CH1 = X INP). cannot be inverted.
The XY mode may generate Lissajous figures which simplify
some measuring tasks and make others possible:
– Comparison of two signals of different frequency or adjust-
ment of one frequency until it is equal to the other and
becomes synchronized.
– This is also possible for multiples or fractions of one of the
frequencies.
Phase measurements with Lissajous figures
The following pictures show two sine waves of equal amplitude
and frequency but differing phase.
Calculation of the phase angle between the X and Ysignals (after
reading a and b off the screen) is possible using the following
formulas and a pocket calculator with trigonometric functions.
This calculation is independent of the signal amplitudes:
Please note:
– As the trigonometric functions are periodic, limit the cal-
culation to angles <90 degrees. This is where this function
is most useful.
– Do not use too high frequencies,
because, as explained above, the
two amplifiers are not identical,
their phase difference increases
with frequency. The spec gives the
frequency at which the phase diffe-
rence will stay <3 degrees.
– The display will not show which of the two frequencies does
lead or lag. Use a CR combination in front of the input of the
frequency tested. As the input has a 1MΩ resistor it will be
sufficient to insert a suitable capacitor in series. If the ellipse
increases with the C compared to the C short circuited the
test signal will lead and vice versa. This is only valid <90
degrees. Hence C should be large and just create a barely
visible change.
If in XY mode, one or both signals may disappear, showing only
a line or a point, mostly very bright. In case of only a point there
is danger of phosphor burn, so turn the intensity down imme-
diately; if only a line is shown the danger of burn will increase
the shorter the line is. Phosphor burn is permanent.
Measurement of phase differences in dual channel
Yt mode
Please note: Do not use ”alternate trigger“ because the time
differences shown are arbitrary and depend only on the respec-
tive signal shapes! Make it a rule to use alternate trigger only
in rare special cases.
The best method of measuring time or phase differences is using
the dual channel Yt mode. Of course, only times may be read off
the screen, the phase must then be calculated as the frequency
is known. This is a much more accurate and convenient method
as the full bandwidth of the scope is used, and both amplifiers
are almost identical. Trigger the time base from the signal
which will be the reference. It is necessary to position both
traces without signal exactly on the graticule center (POSITION
1 and 2). The variables and trigger level controls may be used,
this will not influence the time difference measurement. For
best accuracy display only one period at high amplitude and
observe the zero crossings. One period equals 360 degrees.
It may be advantageous to use ac coupling if there is an offset
in the signals.
In this example t = 3 cm and T = 10 cm, the phase difference in
degrees will result from:
5 3
ϕ° =
— ·360° = — ·360° = 108°
T 10
or in angular units:
t 3
arc ϕ° =
— · 2π= — · 2π= 1,885 rad
T 10
Operating modes of the vertical amplifier
t = horizontal spacing of the zero
transitions in div
T= horizontal spacing for one
period in div
0° 35° 90° 180°
ab
a
sin ϕ=
—
b
a
cos ϕ= 1 –
(
—
)2
b
a
ϕ= arc sin
—
b

15
Subject to change without notice
Very small phase differences with moderately high frequencies
may yield better results with Lissajous figures.
However, in order to get higher precision it is possible to switch
to higher sensitivities after accurately positioning at graticule
centre, thus overdriving the inputs resulting in sharper zero
crossings. Also, it is possible to use half a period over the full
10 cm. As the time base is quite accurate, increasing the time
base speed after adjusting for e.g. one period = 10 cm and
positioning the first crossing on the first graticule line will also
give better resolution.
Measurement of amplitude modulation
Please note: Use this only in analog mode because in digital
mode alias displays may void the measurement! For the display
of low modulation frequencies a slow time base (TIME/DIV) has
to be selected in order to display one full period of the modula-
ting signal. As the sampling frequency of any digital oscilloscope
must be reduced at slow time bases it may become too low for
a true representation.
The momentary amplitude at time t of a hf carrier frequency
modulated by a sinusoidal low frequency is given by:
u = UT·sinΩt + 0,5m ·UT·cos (Ω- ω) t - 0,5m ·UT·cos (Ω- ω) t
where: UT= amplitude of the unmodulated carrier
Ω= 2πF = angular carrier frequency
ω= 2πf = modulation angular frequency
m = modulation degree (≤1 v100%)
In addition to the carrier a lower side band F – f and an upper
side band F + f will be generated by the modulation.
Picture 1: Amplitudes and frequencies with AM (m = 50 %) of
the spectra
As long as the frequencies involved remain within the scope’s
bandwidth the amplitude modulated HF can be displayed. Pre-
ferably the time base is adjusted so that several signal periods
will be displayed. Triggering is best done from the modulation
frequency. Sometimes a stable displayed can be achieved by
adjusting the time base variable.
Picture 2: Amplitude modulated hf. F = 1 MHz, f = 1 kHz,
m = 50 %, UT= 28,3 mVrms
Set the scope controls as follows in order to display the picture
2 signal:
CH1 only, 20 mV/cm, AC
TIME/DIV: 0.2 ms/cm
Triggering: NORMAL, AC, internal.
Use the time base variable or external triggering.
Reading a and b off the screen the modulation degree will
result:
a – b a – b
m =
—— bzw. m = —— ·100 [%]
a + b a + b
a = UT (1 + m) and b = UT(1 – m)
When measuring the modulation degree the amplitude and time
variables can be used without any influence on the result.
Triggering and time base
The most important controls and displays for these functions
are to be found in the shaded TRIGGER area, they are described
in „Controls and Readout“.-
In YT mode the signal will deflect the trace vertically while the
time will deflect it horizontally, the speed can be selected.
In general periodic voltage signals are displayed with a peri-
odically repeating time base. In order to have a stable display,
successive periods must trigger the time base at exactly the
same time position of the signal (amplitude and slope).
STOP
Pure DC can not trigger the time base, a voltage
change is necessary.
Triggering may be internal from any of the input signals or
externally from a time related signal.
For triggering a minimum signal amplitude is required which
can be determined with a sine wave signal. With internal trigge-
ring the trigger take off within the vertical amplifiers is directly
following the attenuators. The minimum amplitude is specified
in mm on the screen. Thus it is not necessary to give a minimum
voltage for each setting of the attenuator.
For external triggering the appropriate input connector is used,
thus the input amplitude necessary is given in Vpp. The voltage
for triggering may be much higher than the minimum, however,
it should be limited to 20 times the minimum. Please note that
for good triggering the external voltage should be a good deal
above the minimum. The scope features two trigger modes to
be described in the following:
Automatic peak triggering (MODE menu)
Consult the chapters MODE
20
>AUTO, LEVEL A/B
19
, FILTER
21
and SOURCE
22
in ”Controls and Readout“. Using AUTOSET
this trigger mode will be automatically selected. With DC cou-
pling and with alternate trigger this mode will be left while the
automatic triggering will remain.
Automatic triggering causes a new time base start after the
end of each foregoing sweep and after the hold off time has
Triggering and time base
F – f FF + f
0,5m · UT0,5m · UT
UT
ba
m · UT
UT

16 Subject to change without notice
elapsed even without any input signal. Thus there is always
a visible trace in analog or digital mode. The position of the
trace(s) without any signal is then given by the settings of the
POSITION controls.
As long as there is a signal, scope operation will not need more
than a correct amplitude and time base setting. With signals
<20 Hz their period is longer than the time the auto trigger
circuit will wait for a new trigger, consequently the auto trigger
circuit will start the time base irrespective of the signal. Hence
the the display will not be triggered and free run, quite inde-
pendent of the signal’s amplitude which may be much larger
than the minimum.
Also in auto peak trigger mode, the trigger level control is active.
Its range will be automatically adjusted to coincide with the
signal’s peak to peak amplitude, hence the name. The trigger
point will thus become almost independent of signal amplitu-
de. This means that even if the signal is decreased the trigger
will follow, the display will not lose trigger. As an example: the
duty cycle of a square wave may change between 1:1 and 100:1
without losing the trigger.
Depending on the signal the LEVEL A/B control may have to be
set to one of its extreme positions.
The simplicity of this mode recommends it for most uncompli-
cated signals. It is also preferable for unknown signals.
This trigger mode is independent of the trigger source and
usable as well for internal as external triggering. But the signal
must be >20 Hz.
Normal trigger mode (See menu MODE)
Consult the chapters: MODE
20
>AUTO, LEVEL A/B
19
, FILTER
21
and SOURCE
22
in ”Controls and Readout“. Information
about how to trigger very difficult signals can be found in the
HOR VAR menu
30
where the functions time base, fine adjust-
ment VAR, HOLD OFF time setting, and time base B operation
are explained.
With normal triggering and suitable trigger level setting, trigge-
ring may be chosen on any point of the signal slope. Here, the
range of the trigger level control depends on the trigger signal
amplitude. With signals <1 cm care is necessary.
In normal mode triggering there will be no trace visible in the
absence of a signal or when the signal is below the minimum
trigger amplitude requirement!
Normal triggering will function even with complicated signals. If
a mixture of signals is displayed triggering will require repetition
of amplitudes to which the level can be set. This may require
special care in adjustment.
Slope selection (Menu FILTER)
After entering FILTER
21
the trigger slope may be selected using
the function keys. See also ”Controls and Readout“. AUTOSET
will not change the slope.
Positive or negative slope may be selected in auto or normal
trigger modes. Also, a setting ”both“ may be selected which will
cause a trigger irrespective of the polarity of the next slope.
Rising slope means that a signal comes from a negative po-
tential and rises towards a positive one. This is independent
of the vertical position. A positive slope may exist also in the
negative portion of a signal. This is valid in automatic and
normal modes.
Trigger coupling (Menu: FILTER)
Consult chapters: MODE
20
>AUTO, LEVEL A/B
19
, FILTER
21
and SOURCE
22
in ”Controls and Readout“. In AUTOSET DC
coupling will be used unless ac coupling was selected before.
The frequency responses in the diverse trigger modes may be
found in the specifications.
With internal DC coupling with or without LF filter use normal
triggering and the level control. The trigger coupling selected
will determine the frequency response of the trigger channel.
AC:
This is the standard mode. Below and above the fall off of the
frequency response, more trigger signal will be necessary.
DC:
With direct coupling there is no lower frequency limit, so this
is used with very slowly varying signals. Use normal triggering
and the level control. This coupling is also indicated if the signal
varies in its duty cycle.
HF:
A high pass is inserted in the trigger channel, thus blocking low
frequency interference like flicker, noise etc.
Noise Reject:
This trigger coupling mode or filter is a low pass suppressing
high frequencies. This is useful in order to eliminate hf inter-
ference of low frequency signals. This filter may be used in
combination with DC or ac coupling, in the latter case very low
frequencies will also be attenuated.
LF:
This is also a low pass filter with a still lower cut off frequency
than above which also can be combined with DC or ac coupling.
Selecting this filter may be more advantageous than using DC
coupling in order to suppress noise producing jitter or double
images. Above the pass band the necessary trigger signal will
rise. Together with ac coupling there will also result a low
frequency cut off.
Video (tv triggering)
Selecting MODE >Video will activate the built in TV sync se-
parator. It separates the sync pulses from the picture content
and thus enables stable triggering independent of the changing
video content.
Composite video signals may be positive or negative. The sync
pulses will only be properly extracted if the polarity is correct.
The definition of polarity is as follows: if the video is above the
sync it is positive, otherwise it is negative. The polarity can be
selected after selecting FILTER. If the polarity is wrong the
display will be unstable or not triggered at all as triggering will
then initiated by the video content. With internal triggering a
minimum signal height of 5 mm is necessary.
The PAL sync signal consists of line and frame signals which
differ in duration. Pulse duration is 5 μs in 64 μs intervals. Frame
sync pulses consist of several pulses each 28 μs repeating each
half frame in 20 ms intervals.
Both sync pulses differ in duration and in their repetition inter-
vals. Triggering is possible with both.
Triggering and time base

17
Subject to change without notice
Frame sync pulse triggering
Remark:
Using frame sync triggering in dual trace chopped mode
may result in interference, so here the dual trace alternate
mode should be chosen. It may also be necessary to turn the
readout off.
In order to achieve frame sync pulse triggering call MODE,
select video signal triggering and then FILTER to select frame
triggering. It may be selected further whether ”all“, ”only even“
or ”only odd“ half frames shall trigger. Of course, the correct tv
standard must be selected first of all (625/50 or 525/60).
The time base setting should be selected to suit, with 2 ms/cm
a complete half frame will be displayed. Frame sync pulses
consist of several pulses with a half line rep rate.
Line sync pulse triggering
In order to choose line snyc triggering call MODE and select
VIDEO, enter FILTER, make sure that the correct video standard
is selected (625/50 or 525/60) and select Line.
If ALL was selected each line sync pulse will trigger. It is also
possible to select a line number ”LINE No.“.
In order to display single lines a time base setting of TIME/DIV.
= 10 μs/cm is recommended, this will show 1½ lines. In general
the composite video signal contains a high DC component which
can be removed by ac coupling, provided the picture is steady.
Use the POSITION control to keep the display within the screen.
If the video content changes such as with a regular TV program,
only DC coupling is useful, otherwise the vertical position would
continuously move.
The sync separator is also operative with external triggering.
Consult the specifications for the permissible range of trigger
voltage. The correct slope must be chosen as the external
trigger may have a different polarity from the composite video.
In case of doubt display the external trigger signal.
LINE trigger
Consult SOURCE
22
in ”Controls and Readout“ for specific
information.
If the readout shows Tr:Line the trigger signal will be internally
taken from the line (50 or 60 Hz).
This trigger signal is independent of the scope input signals and
is recommended for all signals synchronous with the line. Within
limits this will also be true for multiples or fractions of the line
frequency. As the trigger signal is taken off internally there is
no minimum signal height on the screen for a stable display.
Hence even very small voltages like ripple or line frequency
interference can be measured.
Please note that with line triggering the polarity switching will
select either the positive or negative half period of the line, not
the slope. The trigger level control will move the trigger point
over most of a half wave.
Line frequency interference may be checked using a search
coil which preferably should have a high number of turns and
a shielded cable. Insert a 100Ω resistor between the center
conductor and the BNC connector. If possible the coil should
be shielded without creating a shorted winding.
Alternate trigger
This mode (only available in analog mode) is selected with
SOURCE
22
>Alt. 1/2. The readout will display Tr:alt, but no
trigger point symbol indicating level and time position. Instead
an arrow pointing upwards will indicate the trigger time posi-
tion if this lies within the screen area. The Trigger symbol is
not indicated.
This trigger mode is to be used with greatest care and should be
an exception rather than the rule, because the time relationships
visible on the screen are completely meaningless, they depend
only on the shape of the signals and the trigger level!
In this mode the trigger source will be switched together with
the channel switching, so that when CH1 is displayed in the dual
channel alternate mode, the trigger is taken from CH1 and when
CH2 is displayed, the trigger is taken from CH2. This way two
uncorrelated signals can be displayed together. If this mode is
inadvertently chosen the time relationships between the signals
will also be lost when both signals are correlated! (Except for the
special case that both happen to be square waves with extremely
fast rise times). Of course, this trigger mode is only possible in
the dual channel alternate mode and also not with external or
line trigger. AC coupling is recommended for most cases.
External triggering
If Yt (time base) mode is present, this trigger mode may be
selected with SOURCE
22
>Extern. In digital mode it is only
possible if channels 3 and 4 are turned off. The readout will dis-
play Tr:ext. CH4
39
will be the input for the external trigger, all
internal sources will be disconnected. In this mode the trigger
point symbol (level and time position) will not be displayed, only
the trigger time position will be indicated. External triggering
requires a signal of 0.3 to 3 Vpp, synchronous with the vertical
input signal(s).
Triggering will also be possible within limits with multiples or
fractions of the vertical input signal frequency. As the trigger
signal may have any polarity, it may happen that the vertical
input signal will start with a negative slope in spite of having
selected positive slope; slope selection refers now to the ex-
ternal trigger.
Indication of triggered operation (TRIG’D LED)
Refer item
23
in ”Controls and Readout“. The LED labelled
TRIG’D indicates triggered operation provided:
– Sufficient amplitude of the internal or external trigger signal.
– The trigger point symbol is not above or below the signal.
If these conditions are met the trigger comparator will output
triggers to start the time base and to turn on the trigger indi-
cation. The trigger indicator is helpful for setting the trigger
up, especially with low frequency signals (use normal trigger)
and very short pulses.
The trigger indication will store and display triggers for 100 ms.
With signals of very low rep rate the indicator will flash accor-
dingly. If more than one signal period is shown on the screen
the indicator will flash each period.
Hold off time adjustment
Consult ”Controls and Readout“ HOR VAR
30
>Hold off time
for specific information.
Triggering and time base

18 Subject to change without notice
After the time base has deflected the trace from left to right,
the trace will be blanked so the retrace is invisible. The next
sweep will, however, not immediately start. Time is required to
perform internal switching, so the next start is delayed for the
so called hold off time, irrespective of the presence of triggers.
The hold off time can be extended from its minimum by a factor
of 10:1. Manipulation of the hold off time and thus of the time for
a complete sweep period from start to start can be useful e.g.
when data packets are to be displayed. It may seem that such
signals can not be triggered. The reason is that the possible
start of a new sweep does not coincide with the start of a data
packet, it may start anywhere, even before a data packet. By
varying the hold off time, a stable display will be achieved by
setting it so that the hold off ends just before the start of a data
packet. This is also handy with burst signals or non periodic
pulse trains.
A signal may be corrupted by noise or hf interference so a double
display will appear. Sometimes varying the trigger level cannot
prevent the double display but will only affect the apparent time
relationship between two signals. Here the variable hold off time
will help to arrive at a single display.
Sometimes a double display will appear when a pulse signal
contains pulses of slightly differing height requiring delicate
trigger level adjustment. Also here increasing the hold off time
will help.
Whenever the hold off time has been increased it should reset
to its minimum for other measurements, otherwise the bright-
ness will suffer as the sweep rep rate will not be maximum. The
following pictures demonstrate the function of the hold off:
Fig. 1: Display with minimum hold off time (basic setting).
Double image, no stable display.
Fig. 2: By increasing the hold off a stable display is achieved.
Time base B (2nd time base). Delaying, Delayed
Sweep. Analog mode
Consult ”Controls and Readout“ HOR VAR
30
and TIME/DIV.
28
for specific information.
As was described in ”Triggering and time base“ a trigger will
start the time base. While waiting for a trigger, after completion
of the hold off time, the trace will remain blanked. A trigger will
cause trace unblanking and the sweep ramp which deflects
the trace from left to right with the speed set with TIME/DIV.
At the end of the sweep the trace will be blanked again and
reset to the start position. During a sweep the trace will also be
deflected vertically by the input signal. In fact the input signal
does continuously deflect the trace vertically, but this will be
only visible during the unblanking time. This is, by the way, one
marked difference to digital operation where the input signal is
only measured during the acquisition time, for most of the time
the digital oscilloscope will not see the signal. Also, in analog
mode the signal itself will be seen on the screen in real time,
whereas a digital oscilloscope can only show some time later
a reconstruction of the signal acquired.
In analog mode the display will always start on the left. Let us
assume one period of a signal is displayed at a convenient time
base setting. Increasing the sweep speed with TIME/DIV. will
expand the display from the start, so that parts of the signal
will disappear from the screen. It is thus possible to expand
the beginning of the signal period and show fine detail, but it
is impossible to show such fine detail for ”later“ parts of the
signal.
The x10 Magnifier (MAG x10) may be used to expand the display
and the horizontal positioning control can shift any part of the
display into the centre, but the factor of 10 is fixed.
The solution requires a second time base, called time base B.
In this mode time base A is called the delaying sweep and
time base B the delayed sweep. The signal is first displayed
by TB A alone. Then TB B is also turned on which is the mode
”A intensified by B“. TB B should always be set to a higher sweep
rate than A, thus its sweep duration will be also shorter than
that of A. The TB A sweep sawtooth is compared to a voltage
which can be varied such that TB A functions as a precision
time delay generator. Depending on the amplitude of the com-
parison voltage a signal is generated anywhere between sweep
start and end.
In one of two operating modes this signal will start TB B imme-
diately. The TB A display will be intensified for the duration of
TB B, so that one sees which portion of the signal is covered by
TB B. By varying the comparison voltage the start of TB B can
be moved over the whole signal as it is displayed by TB A. Then
the mode is switched to TB B. The signal portion thus selected is
now displayed by TB B. This is called „B delayed by A“. Portions
of the signal can thus be expanded enormously, however, the
higher the speed of TB B the darker the display will become as
the rep rate will remain that of the accepted signal triggers while
the duration of TB B is reduced with increasing speed.
In cases where there is jitter the TB B can be switched to wait
for a trigger rather than starting immediately. When a trigger
arrives TB B will be started by it. The jitter is removed, however,
the effect is also, that the TB B start now can be only from signal
period to signal period, no continuous adjustment is possible
in this mode.
Alternate sweep
In this mode the signal is displayed twice, with both time bases.
An artificial Y offset can be added in order to separate the two
displays on the screen. The operation is analogous to Y dual
trace alternate mode, i.e., the signal is alternately displayed by
both time bases, not simultaneously which is not possible with
a single gun crt. TB B operation is the same here.
Triggering and time base
period
heavy parts are displayed
signal
adjusting
HOLD OFF time
sweep
Fig. 1
Fig. 2