Hameg HM 407A User manual

1
Subject to change without notice
Oscilloscope
HM 407A
Table of contents
General information regarding the CE marking .......... 2
General Information ........................................................ 4
Symbols ......................................................................... 4
Use of tilt handle............................................................ 4
Safety ............................................................................. 4
Intended purpose and operating conditions ................. 4
EMC ............................................................................... 5
Warranty......................................................................... 5
Maintenance .................................................................. 5
Protective Switch-Off .................................................... 5
Power supply ................................................................. 5
Type of signal voltage ..................................................... 6
Amplitude Measurements............................................. 6
Total value of input voltage ........................................... 7
Time Measurements ..................................................... 7
Connection of Test Signal ............................................. 8
Controls and readout....................................................... 9
Menu ................................................................................ 22
First Time Operation ..................................................... 23
Trace Rotation TR ........................................................ 23
Probe compensation and use...................................... 23
Adjustment at 1kHz ..................................................... 23
Adjustment at 1MHz ................................................... 24
Operating modes of the vertical
amplifiers in Yt mode................................................... 24
X-Y Operation............................................................... 25
Phase comparison with Lissajous figures .................. 25
Phase difference measurement
in DUAL mode (Yt)....................................................... 25
Phase difference measurement in DUAL mode ........ 25
Measurement of an amplitude modulation ................ 26
Triggering and time base............................................. 26
Automatic Peak (value) -Triggering ............................. 26
Normal Triggering ........................................................ 27
(Slope) .................................................................... 27
Trigger coupling ........................................................... 27
Triggering of video signals........................................... 28
Line triggering (~) ........................................................ 28
Alternate triggering ...................................................... 28
External triggering........................................................ 28
Trigger indicator “TR” ................................................. 29
HOLD OFF-time adjustment ....................................... 29
(Only in analog mode).................................................. 29
Delay / After Delay Triggering ..................................... 29
(Only in analog mode).................................................. 29
Auto Set........................................................................... 31
Save/Recall ..................................................................... 31
Component Tester (analog mode)............................... 31
General......................................................................... 31
Using the Component Tester...................................... 32
Test Procedure ............................................................ 32
Test Pattern Displays................................................... 32
Testing Resistors ......................................................... 32
Testing Capacitors and Inductors................................ 32
Testing Semiconductors.............................................. 32
Testing Diodes ............................................................. 32
Testing Transistors ...................................................... 32
In-Circuit Tests............................................................. 33
Storage Mode ................................................................. 33
Signal recording modes ............................................... 34
Vertical resolution ........................................................ 34
Horizontal resolution.................................................... 34
Maximum signal frequency in storage mode ............. 34
Alias signal display ....................................................... 35
Operating modes of the vertical amplifiers ................ 35
Test Instructions ............................................................ 35
General ......................................................................... 35
Cathode-Ray Tube: Brightness and Focus,
Linearity, Raster Distortion.......................................... 35
Astigmatism Check...................................................... 35
Symmetry and Drift of the Vertical Amplifier ............. 35
Calibration of the Vertical Amplifier............................. 36
Transmission Performance.......................................... 36
of the Vertical Amplifier............................................... 36
Operating Modes:CH.I/II, DUAL, ADD, CHOP.,
INVERT and X-Y Operation.......................................... 36
Triggering Checks ........................................................ 36
Time base..................................................................... 37
Hold Off time (analog mode only)............................... 37
Component Tester....................................................... 37
Trace Alignment........................................................... 37
Service Instructions ....................................................... 37
General ......................................................................... 37
Instrument Case Removal........................................... 37
Caution ......................................................................... 38
Operating Voltages ...................................................... 38
Maximum and Minimum Brightness .......................... 38
Astigmatism control .................................................... 38
Trigger Threshold......................................................... 38
Trouble-Shooting the Instrument................................ 38
Adjustments................................................................. 39
RS232 Interface - Remote Control ............................... 39
Safety ........................................................................... 39
Operation ..................................................................... 39
RS-232 Cable ............................................................... 39
RS-232 protocol ........................................................... 39
Baud-Rate Setting........................................................ 39
Data Communication ................................................... 39
Front Panel HM407......................................................... 40
St.090798-Hüb/goRR
GB

2Subject to change without notice
KONFORMITÄTSERKLÄRUNG
DECLARATION OF CONFORMITY
DECLARATION DE CONFORMITE
Instruments
Herstellers HAMEG GmbH
Manufacturer Kelsterbacherstraße 15-19
Fabricant D - 60528 Frankfurt
Bezeichnung / Product name / Designation:
Oszilloskop/Oscilloscope/Oscilloscope
Typ / Type / Type: HM407
mit / with / avec: -
Optionen / Options / Options: HO79-6
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: 1993 / IEC (CEI) 1010-1: 1990 A 1: 1992 / VDE 0411: 1994
Überspannungskategorie / Overvoltage category / Catégorie de surtension: II
Verschmutzungsgrad / Degree of pollution / Degré de pollution: 2
Elektromagnetische Verträglichkeit / Electromagnetic compatibility
Compatibilité électromagnétique
EN 50082-2: 1995 / VDE 0839 T82-2
ENV 50140: 1993 / IEC (CEI) 1004-4-3: 1995 / VDE 0847 T3
ENV 50141: 1993 / IEC (CEI) 1000-4-6 / VDE 0843 / 6
EN 61000-4-2: 1995 / IEC (CEI) 1000-4-2: 1995 / VDE 0847 T4-2
Prüfschärfe / Level / Niveau = 2
EN 61000-4-4: 1995 / IEC (CEI) 1000-4-4: 1995 / VDE 0847 T4-4:
Prüfschärfe / Level / Niveau = 3
EN 50081-1: 1992 / EN 55011: 1991 / CISPR11: 1991 / VDE0875 T11: 1992
Gruppe / group / groupe = 1, Klasse / Class / Classe = B
Datum /Date /Date Unterschrift / Signature /Signatur
02.03.1998
Dr. J. Herzog
Technical Manager/Directeur Technique
®
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 emmission and immunity and therefore
on meeting the acceptance limits. For different applications the lines and/or cables used may be different. For
measurementoperation the followinghints and conditionsregardingemission and immunityshouldbe observed:
1. Data cables
For the connection between instruments resp. their 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 long. 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 cables
HZ72S and HZ72L from HAMEG are 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 long.
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.
3. Influence on measuring instruments.
Underthe presence ofstronghigh frequency electricormagnetic fields, evenwithcareful setup ofthemeasuring
equipment an 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.
HAMEG GmbH

3
Subject to change without notice
Accessories supplied: Line Cord, Operators Manual, 2 Probes1:1/ 10:1
Screen photo of stored sinewave signals. Screen shot of measurement software.
The worldwide success of HAMEG´s HM205 and HM305 has led to the
introduction of the new microprocessor controlled HM407 Analog/Digital
oscilloscope. This instrument offers much more performance and specifications
over its predecessores. The HM407incorporates a microprocessor-basedsystem
that extensively automates operation. The majority of signals can be displayed by
simply pressing the “Autoset“ button. A “Save/Recall“ function is available for
storing frequently used setup parameters.
The increased maximum sampling rate of 100MS/s now allows to capture a
10MHzsignal in “Single“ mode with 10 samples(dots) per period. The automatic
Dot-Join function provides linear connections between the captured points,
ensuring that all digitized signals are displayed without gaps. New features are the
two reference memories, allowing their contents to be compared with the live
signal at any time. Cursors can be activated for waveform measurements. All
important parameter settings are displayed on the CRT screen. The built-in RS232-
Interface enables remote control operation and signal processing via a PC.
Unique in its price range is also the analog section of the HM407. The increased
bandwidth of 40MHz (-3dB) allows the stable display of signals up to 100MHz. As
always, the Component Tester with one-button control is a standard feature in
the HM407. This is also true for the switchable 1kHz/1MHz Calibrator which
permits you to check the transient characteristics from probe tip to the screen at
any time.
All in all, the new HM407 presents itself as a practical hands-on oscilloscope for
today’s progressive measurement requirements offering a price/performance ra-
tio that sets new standards world-wide.
Specifications
Vertical Deflection
Operating modes: Channel I or CH II separate,
Channel I and II: alternate or chopped
(Chopper Frequency approx. 0.5MHz)
Sum or Difference from Channel I and ± Ch. II,
XY-Mode: via CH I (X) and CH II (Y).
Frequency range: 2x DC to 40MHz (−3dB).
Risetime: <8.75ns. Overshoot: ≤1%.
Deflection coefficient: 14 calibrated positions
variable 2.5:1 to min. 50V/div.
1mV/div and 2mV/div: ±5% (0 to 10MHz (-3dB))
5mV/div to 20V/div: ±3% (1-2-5sequence).
Input impedance: 1MΩII 15pF.
Input coupling: DC - AC - GD (Ground)
Input voltage: max. 400V (DC + peak AC).
Triggering
Automatic(peak to peak):≤≤
≤≤
≤20Hz-100MHz(≤0.5div),
Normal: DC-100MHz, LED for trigger indication.
Slope: positive or negative.
Sources: CH I or II, line, ext.
CH I alternate CH II (≤ 0.8div.)
Coupling: AC (≥10Hz -100MHz), DC (0-100MHz),
HF (50kHz - 100MHz), LF (0 - ≤1.5kHz).
Triggering ext.: ≥0.3Vpp from DC to 100MHz
Active TV-Sync-Separator (field & line, pos, neg.)
2nd triggering (Del. Trig.): normal with level
control DC to 100 MHz.
Horizontal Deflection
Time coefficients: 1-2-5 sequence, Accuracy ±3%
Analog: 22 cal. positions from 0.5s - 50ns/div.
Digital: 25 cal. positions from 100s - 1µs/div.
Variable (analog) 2.5:1 up to 1.25s/div.
X-MAG. x10: analogto10ns/div.,dig.to0.1µs/div ±5% .
Delay: 120ms - 200ns, variable,
Hold-off time (analog):variable to approx. 10:1.
Bandwidth X-amplifier (analog): 0-3MHz (−3dB).
InputX-amplifierviaChannelII, Sensitivitysee ChannelII.
X-Y-phase shift : <3° below 120kHz.
Digital Storage
Operating modes: Refresh, Roll, Single, XY,
Envelope, Average (2 to 512 waveforms).
Automatic Dot Join function
Sample Rate: max. 100MS/s (8 bit)
Refresh rate: max. 180/s
Record length: 2048 x 8 bit per channel.
Reference memoryReference memory
Reference memoryReference memory
Reference memory: 2 x 2k x 8bit (EEPROM).
Resolution: Y: 25 points/div, X: 200 points/div.
Pre-/Posttrigger: 25, 50, 75, 100, -25, -50, -75%.
Operation / Control
Manual (front panel switches);
Auto Set (automatic parameter selection).
Save/Recall of 9 user-defined parameter settings
RS232 interface for remote control via a PC.
Remote control (Option) HZ68.
Multifunction- Interface HO79-6(Option): RS232,
IEEE-488, Centronics (Postscript, HPGL, PCL, EPSON).
Readout: Display of parameter settings.
Cursor measurement of ∆V, ∆t or ∆1/t (frequency),
separate or in tracking mode.
Component Tester
Test voltage: approx. 7Vrms (open circuit).
Test current: max. 7mArms (short circuit).
Test frequency: approx.50Hz
One test lead is grounded (Safety Earth).
GeneralInformation
CRT: D14-364GY/123 or ER151-GH/-,rectangular
screen (8x10cm) internal graticule
Acceleration voltage: approx 2000V
Trace rotation: adjustable on front panel
Calibrator: square-wave generator (tr<4ns)
≈1kHz/1MHz; Output: 0.2V ±1%.
Analog Intensitymodulation, max. +5V (TTL).
Line voltage: 100-240V AC ±10%, 50/60Hz
Power consumption: approx. 42 Watt at 50Hz.
Min./Max. ambient temperature: 0°C...+40°C
Protective system: Safety class I (IEC1010-1)
Weight: approx. 5.6kg, color: techno-brown
Cabinet: W 285, H 125, D 380 mm 3/98
Auto-Set, Save/Recall, Readout/Cursor, RS232 Interface
Analog: 2 x DC-40MHz, max. 1mV/div, Timebase 0.5s/div - 10ns/div
Triggering DC - 100MHz, Component Tester, 1MHz Calibrator
Digital: Max. Sampling Rate 100MS/s, Timebase 100s/div - 0.1µs/div
Storage 2 x 2048 x 8 bit, Reference Memory, Post/Pre-Trigger
Storage Modes: Refresh, Single, Roll, Average and Envelope
40MHz Analog-/Digital-Scope HM407

4Subject to change without notice
General Information
This oscilloscope is easy to operate. The logical arrangement
of the controls allows anyone to quickly become familiar with
the operation of the instrument, however, experienced users
are also advised to read through these instructions so that all
functions are understood.
Immediatelyafterunpacking,theinstrumentshouldbechecked
for mechanical damage and loose parts in the interior. If there
is transport damage, the supplier must be informed
immediately. The instrument must then not be put into
operation.
Symbols
ATTENTION - refer to manual
Danger - High voltage
Protective ground (earth) terminal
Use of tilt handle
To view the screen from the best angle, there are three
differentpositions (C,D,E) forsetting uptheinstrument. Ifthe
instrument is set down on the floor after being carried, the
handle automatically remains in the upright carrying position
(A). In order to place the instrument onto a horizontal surface,
thehandleshouldbeturnedtotheuppersideoftheoscilloscope
(C). For the D position (10° inclination), the handle should be
turned to the opposite direction of the carrying 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 carrying by turning it to the upper side to lock in the
B position. At the same time, the instrument must be lifted,
because otherwise the handle will jump back.
Safety
This instrument has been designed and tested in accordance
with IEC Publication 1010-1 (overvoltage category II, pollution
degree 2), Safety requirements for electrical equipment for
measurement, control, and laboratory use. The CENELEC
regulations EN 61010-1 correspond to this standard. It has left
thefactoryinasafecondition.Thisinstructionmanualcontains
importantinformationandwarnings whichhavetobefollowed
by the user to ensure safe operation and to retain the
oscilloscope in a safe condition.
The case, chassis and all measuring terminals are connected
to the protective earth contact of the appliance inlet. The
instrument operates according to Safety Class I (three-
conductor power cord with protective earthing conductor and
a plug with earthing contact).
The mains/line plug shall only be inserted in a socket outlet
provided with a protective earth contact. The protective action
must not be negated by the use of an extension cord without
a protective conductor.
Themains/lineplugmustbeinsertedbeforeconnections
are made to measuring circuits.
The grounded accessible metal parts (case, sockets, jacks)
and the mains/line supply contacts (line/live, neutral) of the
instrument have been tested against insulation breakdown
with 2200V DC.
Under certain conditions, 50Hz or 60Hz 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)
between the mains/line outlet and the power plug of the
device being investigated.
Most cathode-ray tubes develop X-rays. However, the dose
equivalent rate falls far below the maximum permissible value
of 36pA/kg (0.5mR/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 impa-
ired if, for example, the instrument
• shows visible damage,
• fails to perform the intended measurements,
• hasbeen subjectedtoprolonged storageunderunfavorable
conditions (e.g. in the open or in moist environments),
• has been subject to severe transport stress (e.g. in poor
packaging).
Intended purpose and operating conditions
This instrument must be used only by qualified experts who
are aware of the risks of electrical measurement.
The instrument is specified for operation in industry, light
industry, commercial and residential environments.
Due to safety reasons the instrument must only be connected
to a properly installed power outlet, containing a protective
earth conductor. The protective earth connection must not be
broken. The power plug must be inserted in the power outlet
while any connection is made to the test device.
The instrument has been designed for indoor use. The
permissible ambient temperature range during operation is
+10°C (+50°F) ... +40°C (+104°F). It may occasionally be
subjected to temperatures between +10°C (+50°F) and -10°C
(+14°F) without degrading its safety. The permissible ambient
temperature range for storage or transportation is -40°C (-
40°F) ... +70°C (+158°F). The maximum operating altitude is
up to 2200m (non-operating 15000m). The maximum relative
humidity is up to 80%.
If condensed water exists in the instrument it should be
acclimatizedbeforeswitchingon.Insomecases(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
General Information

5
Subject to change without notice
explosive, corrosive, dusty, or moist environments. The
oscilloscopecanbeoperatedinanyposition,buttheconvection
coolingmust notbeimpaired.The ventilationholesmay notbe
covered. For continuous operation the instrument should be
used in the horizontal position, preferably tilted upwards,
resting on the tilt handle.
The specifications stating tolerances are only valid if
the instrument has warmed up for 30minutes at an
ambient temperature between +15°C (+59°F) and +30°C
(+86°F). Values without tolerances are typical for an
average instrument.
EMC
ThisinstrumentconformstotheEuropeanstandardsregarding
the electromagnetic compatibility. The applied standards are:
Generic immunity standard EN50082-2:1995 (for industrial
environment) Generic emission standard EN50081-1:1992
(for residential, commercial and light industry environment).
Thismeans that theinstrument hasbeen testedto thehighest
standards.
Pleasenotethatunderthe influenceofstrongelectromagnetic
fields, such signals may be superimposed on the measured
signals.
Under certain conditions this is unavoidable due to the
instrument’s high input sensitivity, high input impedance and
bandwidth. Shielded measuring cables, shielding and earthing
ofthedeviceundertestmayreduceoreliminatethoseeffects.
Warranty
HAMEG warrants to its Customers that the products it
manufactures and sells will be free from defects in materials
and workmanship for a period of 2 years. This warranty shall
not apply to any defect, failure or damage caused by improper
use or inadequate maintenance and care. HAMEG shall not be
obligedtoprovideserviceunderthiswarrantytorepairdamage
resulting from attempts by personnel other than HAMEG
representatives to install, repair, service or modify these
products.
In order to obtain service under this warranty, Customers
must contact and notify the distributor who has sold the
product. Each instrument is subjected to a quality test with 10
hour burn-in before leaving the production. Practically all early
failures are detected by this method. In the case of shipments
by post, rail or carrier it is recommended that the original
packingiscarefullypreserved.Transportdamagesanddamage
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 atthesame timethename andtelephonenumber
(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.
Maintenance
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 accuracy
on which the technical data are based. The test methods
described in the test plan of this manual can be performed
withoutgreatexpenditureonmeasuringinstruments.However,
purchase of the HAMEG scope tester 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
+1% 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.
Protective Switch-Off
Thisinstrumentisequippedwith aswitchmodepowersupply.
It has both overvoltage and overload protection, which will
cause the switch mode supply to limit power consumption to
a minimum. In this case a ticking noise may be heard.
Power supply
The oscilloscope operates on mains/line voltages between
100VACand240VAC.Nomeans ofswitchingtodifferentinput
voltages has therefore been provided.
Thepowerinputfusesareexternallyaccessible.Thefuseholder
is located above the 3-pole power connector. The power input
fuses are externally accessible, if the rubber connector is
removed. The fuseholder can be released by pressing its
plastic retainers with the aid of a small screwdriver. The
retainersare locatedon theright andleftside ofthe holderand
must be pressed towards the center. The fuse(s) can then be
replaced and pressed in until locked on both sides.
Use of patched fuses or short-circuiting of the fuseholder is
not permissible; HAMEG assumes no liability whatsoever for
any damage caused as a result, and all warranty claims
become null and void.
Fuse type:
Size 5x20mm; 0.8A, 250V AC fuse;
must meet IEC specification 127,
Sheet III (or DIN 41 662
or DIN 41 571, sheet 3).
Time characteristic: time-lag (T).
Attention!
There is a fuse located inside the instrument within the
switch mode power supply:
Size 5x20mm; 0.8A, 250V AC fuse;
must meet IEC specification 127,
Sheet III (or DIN 41 662
or DIN 41 571, sheet 3).
Time characteristic: fast (F).
This fuse must not be replaced by the operator!
General Information

6Subject to change without notice
Type of signal voltage
The oscilloscope HM407 allows examination of DC voltages
and most repetitive signals in the frequency range up to at
least 40MHz (-3dB).
The vertical amplifiers have been designed for minimum
overshoot and therefore permit a true signal display.
The display of sinusoidal signals within the bandwidth limits
causes no problems, but an increasing error in measurement
due to gain reduction must be taken into account when
measuring high frequency signals. This error becomes
noticeable at approx. 14MHz. At approx. 18MHz the reduction
is approx. 10% and the real voltage value is 11% higher. The
gain reduction error can not be defined exactly as the -3dB
bandwidthoftheamplifiersdifferbetween40MHzand42MHz.
For sinewave signals the -6dB limit is approx. 50MHz.
When examining square or pulse type waveforms, attention
must be paid to the harmonic content of such signals. The
repetition frequency (fundamental frequency) of the signal
must therefore be significantly smaller than the upper limit
frequency of the vertical amplifier.
Displaying composite signals can be difficult, especially if they
contain no repetitive 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 function or the delayed time base may
be required. Television video signals are relatively easy to
trigger using the built-in TV-Sync-Separator (TV).
For optional operation as a DC or AC voltage amplifier, each
vertical amplifier input is provided with a DC/AC switch. DC
couplingshouldonlybeusedwithaseries-connectedattenuator
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 coupling is also
recommended for the display of logic and pulse signals,
especiallyifthepulsedutyfactorchangesconstantly.Otherwise
the display will move upwards or downwards at each change.
Pure direct voltages can only be measured with DC-coupling.
Theinput couplingisselectable bytheAC/DC pushbutton.The
actual setting is displayed in the readout with the ” = ”symbol
for DC- and the ” ~” symbol for AC coupling.
Amplitude Measurements
In general electrical engineering, alternating voltage data
normally refers to effective values (rms = root-mean-square
value).However,forsignalmagnitudesandvoltagedesignations
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.
Ifasinusoidalwaveform,displayedontheoscilloscopescreen,
is to be converted into an effective (rms) value, the resulting
peak-to-peakvaluemustbedividedby2x√2=2.83.Conversely,
it should be observed that sinusoidal voltages indicated in
Vrms (Veff) have 2.83 times the potential difference in Vpp.
The relationship between the different voltage magnitudes
can be seen from the following figure.
Voltage values of a sine curve
Vrms = effective value; Vp = simple peak or crest value;
Vpp = peak-to-peak value; Vmom = momentary value.
The minimum signal voltage which must be applied to the Y
input for a trace of 1div height is 1mVpp (± 5%) when this
deflection coefficient is displayed on the screen (readout) and
the vernier is switched off (VAR-LED dark). However, smaller
signals than this may also be displayed. The deflection
coefficients 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 x10 is used, a
further multiplication by a factor of 10 is required to ascertain
the correct voltage value.
For exact amplitude measurements, the variable control (VAR)
must be set to its calibrated detent CAL position.
With the variable control activated the deflection sensitivity
can be reduced up to a ratio of 2.5 to 1 (please note “controls
and readout”). Therefore any intermediate value is possible
within the 1-2-5 sequence of the attenuator(s).
With direct connection to the vertical input, signals up
to 400Vpp may be displayed (attenuator set to 20V/div,
variable control to 2.5:1).
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 value can be calculated from the two given
quantities:
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 1mVpp and 160Vpp,
D between 1mV/div and 20V/div in 1-2-5 sequence.
Examples:
Set deflection coefficient D = 50mV/div 0.05V/div,
observed display height H = 4.6div,
required voltage U = 0.05x4.6 = 0.23Vpp.
Input voltage U = 5Vpp,
set deflection coefficient D = 1V/div,
required display height H = 5:1 = 5div.
Type of signal voltage

7
Subject to change without notice
Signal voltage U = 230Vrmsx2 √ 2 = 651Vpp
(voltage > 160Vpp, with probe 10:1: U = 65.1Vpp),
desired display height H = min. 3.2div, max. 8div,
max. deflection coefficient D = 65.1:3.2 = 20.3V/div,
min. deflection coefficient D = 65.1:8 = 8.1V/div,
adjusted deflection coefficient D = 10V/div.
ThepreviousexamplesarerelatedtotheCRTgraticulereading.
The results can also be determined with the aid of the DV
cursor measurement (please note “controls and readout”).
The input voltage must not exceed 400V, independent from
the polarity.
If an AC voltage which is superimposed on a DC voltage is
applied, the maximum peak value of both voltages must not
exceed + or - 400V. So for AC voltages with a mean value of
zero volt the maximum peak to peak value is 800Vpp.
If attenuator probes with higher limits are used, the probes
limits are valid only if the oscilloscope is set to DC input
coupling.
If DC voltages are applied under AC input coupling conditions
the oscilloscope maximum input voltage value remains 400V.
The attenuator consists of a resistor in the probe and the 1MΩ
inputresistorof theoscilloscope,whichare disabledbytheAC
inputcouplingcapacitywhenACcouplingisselected.Thisalso
applies to DC voltages with superimposed AC voltages. It also
must be noted that due to the capacitive resistance of the AC
input coupling capacitor, the attenuation ratio depends on the
signalfrequency.Forsinewavesignalswithfrequencieshigher
than 40Hz this influence is negligible.
With the above listed exceptions HAMEG 10:1 probes can be
used for DC measurements up to 600V or AC voltages (with
a mean value of zero volt) of 1200Vpp. The 100:1 probe HZ53
allows for 1200V DC or 2400Vpp for AC.
It should be noted that its AC peak value is derated at higher
frequencies. If a normal x10 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
displayedon theoscilloscope, anormal x10probeis sufficient.
In this case, an appropriate high voltage capacitor (approx. 22-
68nF) must be connected in series with the input tip of the
probe.
With Y-POS. control (input coupling to GD) it is possible to use
a horizontal graticule line as reference line for ground potential
before the measurement. It can lie below or above the horizon-
tal central line according to whether positive and/or negative
deviations from the ground potential are to be measured.
Total value of input voltage
The dotted line shows a voltage alternating at zero volt level.
If superimposed on a DC voltage, the addition of the positive
peak and the DC voltage results in the max. voltage (DC +
ACpeak).
Time Measurements
Asarule,mostsignalstobedisplayedareperiodicallyrepeating
processes, also called periods. The number of periods per
second is the repetition frequency. Depending on the time
base setting (TIME/DIV.-knob) indicated by the readout, one or
several signal periods or only a part of a period can be
displayed. The time coefficients are stated in ms/div, µs/div or
ns/div.The followingexamplesare relatedtothe CRTgraticule
reading. The results can also be determined with the aid of the
∆T and 1/∆T cursor measurement (please note “ controls and
readout”).
The duration of a signal period or a part of it is determined by
multiplying the relevant time (horizontal distance in div) by the
(calibrated) time coefficient displayed in the readout.
Uncalibrated, the time base speed can be reduced until a
maximum factor of 2.5 is reached. Therefore any intermediate
value is possible within the 1-2-5 sequence.
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 ms, µs or ns/div and the relation
F = 1/T, the following equations can be stated:
However, these four values are not freely selectable. They
have to be within the following limits:
L between 0.2 and 10div, if possible 4 to 10div,
T between 10ns and 5s,
F between 0.5Hz and 100MHz,
Tc between 100ns/div and 500ms/div in 1-2-5 sequence
(with X-MAG. (x10) inactive), and
Tc between 10ns/div and 50ms/div in 1-2-5 sequence
(with X-MAG. (x10) active).
Examples:
Displayed wavelength L = 7div,
set time coefficient Tc = 100ns/div,
required period T = 7x100x10
-9
= 0.7µs
required rec. freq. F = 1:(0.7x10
-6
) = 1.428MHz.
Signal period T = 1s,
set time coefficient Tc = 0.2s/div,
required wavelength L = 1:0.2 = 5div.
Displayed ripple wavelength L = 1div,
set time coefficient Tc = 10ms/div,
required ripple freq. F = 1:(1x10x10
-3
) = 100Hz.
TV-line frequency F = 15625Hz,
set time coefficient Tc = 10µs/div,
required wavelength L = 1:(15 625x10
-5
) = 6.4div.
Sine wavelength L = min. 4div, max. 10div,
Frequency F = 1kHz,
max. time coefficient Tc = 1:(4x10
3
) = 0.25ms/div,
min. time coefficient Tc = 1:(10x10
3
) = 0.1ms/div,
set time coefficient Tc = 0.2ms/div,
required wavelength L = 1:(10
3
x0.2x10
-3
) = 5div.
Type of signal voltage

8Subject to change without notice
Displayed wavelength L = 0.8div,
set time coefficient Tc = 0.5µs/div,
pressed X-MAG. (x10) button: Tc = 0.05µs/div,
required rec. freq. F = 1:(0.8x0.05x10
-6
) = 25MHz,
required period T = 1:(25x10
6
) = 40ns.
If the time is relatively short as compared with the complete
signalperiod,anexpandedtimescaleshouldalwaysbeapplied
(X-MAG. (x10) active). In this case, the time interval of interest
can be shifted to the screen center using the X-POS. control.
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 10% and 90% of the vertical pulse height.
For measurement, adjust the Y deflection coefficient using its
variable function (uncalibrated) together with the Y-POS.
controlsothatthepulseheightispreciselyalignedwiththe0%
and 100% lines of the internal graticule. The 10% and 90%
points of the signal will now coincide with the 10% and 90%
graticule lines. The risetime is given by the product of the
horizontaldistance indiv betweenthesetwo coincidentpoints
and the calibrated time coefficient setting. The fall time of a
pulse can also be measured by using this method.
The following figure shows correct positioning of the
oscilloscope trace for accurate risetime measurement.
With a time coefficient of 10ns/div (X x10 magnification
active),theexampleshownintheabove figureresults ina total
measured risetime of
ttot = 1.6div x 10ns/div = 16ns
Whenvery fastrisetimesare beingmeasured, therisetimesof
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 following formula.
In this ttot is the total measured risetime, tosc is the risetime of
the oscilloscope amplifier (approx. 8.75ns), and tpthe risetime
of the probe (e.g. = 2ns). If ttot is greater than 100ns, then ttot
can be taken as the risetime of the pulse, and calculation is
unnecessary.
Calculationoftheexampleinthefigureaboveresultsinasignal
risetime
tr= √162- 8.752- 22 = 13.25ns
The measurement of the rise or fall time is not limited to the
trace dimensions shown in the above diagram. It is only
particularly 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
interestisvisibleinitsfulllengthatnottoogreatsteepnessand
that the horizontal distance at 10% and 90% of the amplitude
is measured. If the edge shows rounding or overshooting, the
100%should notberelatedto thepeakvalues buttothe 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
meaning. For amplifiers with approximately constant group
delay (therefore good pulse transmission performance) the
following numerical relationship between rise time tr (in ns)
and bandwidth B (in MHz) applies:
Connection of Test Signal
In most cases briefly depressing the AUTO SET causes a
useful signal related instrument setting. The following
explanations refer to special applications and/or signals,
demanding a manual instrument setting. The description of
thecontrols isexplainedinthe section“controlsand readout”.
Caution:
When connecting unknown signals to the oscilloscope
input,always use ax10probe, automatictriggeringand
set the input coupling switch to DC (readout). The
attenuator should initially be set to 20V/div.
Sometimes the trace will disappear after an input signal has
been applied. Then a higher deflection coefficient (lower input
sensitivity) must be chosen until the vertical signal height is
only 3-8div. With a signal amplitude greater than 160Vpp and
thedeflectioncoefficient(VOLTS/DIV.)incalibratedcondition,
an attenuator probe must be inserted before the vertical input.
If, after applying the signal, the trace is nearly blanked, the
periodofthesignalisprobably substantiallylonger thantheset
time deflection coefficient (TIME/DIV.). It should be switched
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
HZ32 or HZ34, or reduced through a x10 or x100 attenuator
probe. The use of test cables with high impedance circuits is
onlyrecommendedforrelativelylowfrequencies(uptoapprox.
50kHz). For higher frequencies, the signal source must be of
low impedance, i.e. matched to the characteristic resistance
of the cable (as a rule 50Ω). 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
50Ωcable such as the HZ34, a 50Ωthrough 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
terminationisnotused.Aterminatingresistanceissometimes
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 resistor HZ22 will only
dissipate a maximum of 2Watts. This power is reached with
10Vrms or at 28.3Vpp with sine signal. 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 impedance sources are only slightly
loaded (approx. 10MΩII 12pF or 100MΩII 5pF with HZ53).
Therefore, if the voltage loss due to the attenuation of the
Type of signal voltage

9
Subject to change without notice
probe can be compensated by a higher amplitude setting, the
probe should always be used. The series impedance of the
probe provides a certain amount of protection for the input of
the vertical amplifier. Because of their separate manufacture,
all attenuator probes are only partially compensated, therefore
accuratecompensationmustbeperformedontheoscilloscope
(see Probe compensation ).
Standardattenuatorprobesontheoscilloscopenormallyreduce
itsbandwidthand increasetherisetime.In allcaseswherethe
oscilloscope bandwidth must be fully utilized (e.g. for pulses
with steep edges) we strongly advise using the probes HZ51
(x10) HZ52 (x10 HF) and HZ54 (x1 and x10). This can save the
purchase of an oscilloscope with larger bandwidth.
The probes mentioned have a HF-calibration in addition to low
frequencycalibrationadjustment.Thusagroupdelaycorrection
totheupperlimitfrequencyoftheoscilloscopeispossiblewith
the aid of an 1MHz calibrator, e.g. HZ60.
In fact the bandwidth and rise time of the oscilloscope are not
noticeably changed with these probe types and the waveform
reproduction fidelity can even be improved because the probe
canbematchedtotheoscilloscopesindividualpulseresponse.
If a x10 or x100 attenuator probe is used, DC input
coupling must always be used at voltages above 400V.
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 oscilloscope input coupling
capacitor concerned. Its voltage rating is max. 400 V
(DC + peak AC). DC input coupling is therefore of quite
specialimportancewithax100attenuationprobewhich
usually has a voltage rating of max. 1200 V (DC + peak
AC). A capacitor of corresponding capacitance 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 voltage
mustbederatedwithfrequencyusuallyabove20kHz.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 important 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 currents 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,shouldbeused. Inthisway groundand
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
groundingbecauseequalizingcurrentscanflowintheshielding
of the test cables (voltage drop between the protective
conductor connections, caused by external equipment
connected to the mains/line, e.g. signal generators with
interference protection capacitors).
Controls and readout
The following description assumes that the operating mode
“COMPONENT TEST”isswitchedoff.
Allimportantmeasuring
parameter settings are displayed in the screen readout when
the oscilloscope is on.
The LED indicators on the large front panel facilitate operation
and provide additional information. Electrical end positions of
controls are indicated by acoustic signal (beep).
Allcontrols,exceptthepower switch(POWER),thecalibration
frequency pushbutton (CAL. 1kHz/1MHz), the FOCUS control
and the trace rotation control, are electronically set and
interrogated. Thus, all electronically set functions and their
current settings can be stored and also remotely controlled.
Some controls are only operative in the digital mode or have a
differentfunction.Explanationspertainingtothemareindicated
with the hint “storage mode only”.
The large front panel is, as is usual with Hameg oscilloscopes,
is marked with several fields.
ThefollowingcontrolsandLEDindicatorsarelocatedonthe
top, to the right of the screen, above the horizontal line:
(1) POWER- Pushbuttonand symbols for ON (I)and OFF (O).
After the oscilloscope is switched on, all LEDs are lit and
an automated instrument test is performed. During this
time the HAMEG logo and the software version are
displayedonthescreen.Aftertheinternaltestiscompleted
successfully, the overlay is switched off and the normal
operation mode is present. Then the last used settings
becomeactivatedandoneLEDindicatestheONcondition.
Itis possibletomodify certainfunctions(SETUP) ortocall
automaticcalibrationprocedures(CALIBRATE).
Fordetails
relating to this see section “MENU”
.
(2) AUTOSET - Pushbutton
Brieflydepressingthispushbutton resultsin anautomatic
instrument setting automatically selecting Yt mode. The
instrument is set to the last used Yt mode setting (CH I,
CH II or DUAL).
SEARCH (SEA) and DELAY (DEL and DTR) mode is
automatically switched off.
Please note “AUTO SET” .
AutomaticCURSORsupportedvoltagemeasurement
IfCURSORvoltagemeasurementispresent,theCURSOR
lines are automatically set to the positive and negative
peak value of the signal. The accuracy of this function
dependson thesignalfrequency andisalso influencedby
the signal‘s pulse duty factor. If the signal height is
insufficient, the CURSOR lines do not change. In DUAL
mode the CURSOR lines are related to the signal which
is used for internal triggering.
STORAGE MODE ONLY
Additionally, AUTO SET automatically selects refresh
mode(RFR)whenSINGLE(SGL)orROLL(ROL)function
is in operation.
Automatic CURSOR supported measurement
In contrast to analog mode, AUTO SET also causes an
automatic CURSOR line setting if time or frequency
measurement has been selected and at least one signal
period is displayed. Neither the signal frequency nor the
pulse duty factor have an effect on the accuracy when
CURSOR voltage measurement is chosen.
(3) RM - LED
The remote control mode can be switched on or off
(”RM” LED dark) via the RS232 interface. On condition
Controls and readout

10 Subject to change without notice
that the “RM” LED is lit, all electronically selectable
controls on front panel are inactive. This state can be left
by depressing the AUTOSETpushbutton provided it was
not deactivated via the interface.
STORAGE MODE ONLY
The RM-LED is lit during data transfer via the built in
RS232 interface. At this time the controls are inactive.
(4) INTENS - READOUT - Control knob with associated
pushbutton and LEDs.
Thiscontrol knobis foradjusting thetrace (A)and readout
intensity (RO).Turning thisknob clockwiseincreases and
turning it counterclockwise decreases the intensity.
The READOUT pushbutton below is for selecting the
function in two ways. If the readout (RO) is not switched
off, briefly pressing the READOUT pushbutton switches
over the INTENS knob function indicated by a LED in the
sequence:
Yt (time base) mode: A - RO - A
XY mode: A - RO - A.
Component Test: A - RO - A.
PressingandholdingtheREADOUTpushbuttonswitches
thereadouton oroff.In readoutoffconditionthe INTENS
knob function can consequently not be set to RO.
Switchingthe readoutoff, may berequired ifinterference
is visible on the signal(s). Such interference may also
originate from the chopper generator if the instrument is
operated in chopped DUAL mode.
Withtheexceptionoftheletters“CT”allotherREADOUT
informationisswitchedoffinCOMPONENTTESTmode.
All INTENS settings are stored after the instrument is
switched off.
The AUTOSET function switches the readout on. The
INTENS setting for each function is automatically set to
the mean value, if less intensity was previously selected.
(5) TR - Trimming potentiometer.
The trace rotation control can be adjusted with a small
screwdriver (
please note “trace rotation TR” )
(6) FOCUS - Control knob.
This control knob effects both the trace and the readout
sharpness.
(7) STOR. ON / HOLD - Pushbutton with two functions.
STOR. ON
Pressing and holding the button switches from analog (Yt
or XY) to storage mode and vice versa. If CT (Component
Tester) mode is present (only available in analog mode),
it must be switched off first to enable switching over to
storage mode.
The oscilloscope is in analog mode if none of the LED’s
associated with the STOR.MODE (9) pushbuttons are lit
anda pre-orpost-trigger value(PT...%)is notindicatedby
the readout. Pressing and holding the STOR. ON button
switches over to the digital mode, but without changing
the channel operating mode (CH I, CH II, DUAL, ADDand
XY). The actual signal capture mode is indicated by one
oftheSTOR. MODE-LED‘s(RFR- ENV - AVM-ROL)and
in addition displayed by the readout. In digital XY mode
the RFR-LED is lit and the readout indicates XY. If digital
SINGLEevent(SGL)capture modeisselected,allSTOR.
MODE-LED‘s are dark, but the readout displays the pre-
or post-trigger value (PT...%).
Attention!
The time base ranges are dependent on the operating
modeAnalog or Digital (storage).Thefollowingdata relate
to operation without X magnification (X-MAG. x10).
Analog mode:
Time base from 500ms/cm to 50ns/cm
(without trace delay).
With trace delay, from 20ms/cm to 50ns/cm.
Delay ranges from 20ms/cm to 100ns/cm.
Digital mode:
Time bases from 100s/cm to 1µs/cm.
This results in the following behavior when switched
from analog to digital mode and vice versa:
1.If in analog mode, the time base has been selected
between 500ns/cm and 50ns/cm, then on switching
todigitalmode thelowestavailabletime coefficientwill
be automatically selected, i.e. 1µs/cm. If now one
switches back to analog mode without having made
anytime basechangesinthe digitalmode,then thelast
time base selected in the analog mode is again active
(e.g. 500ns/cm).
If on the other hand, the time base is changed after
switching over to digital mode (e.g. to 2µs/cm). Then,
when switched back to analog mode, the time base in
analog mode will be set to the value selected in the
digital mode (e.g. 2µs/cm).
2.If a time base between 100s/cm and 1s/cm has been
set in the digital mode and the mode is switched to
analog,thenthetimebaseinanalogmodeisautomatically
set to 500ms/cm. The rest is as described before.
The X-MAG x10 setting remains unchanged when
switched from analog to digital mode and vice versa.
STORAGE MODE ONLY
If by pressing and holding the STOR. ON / HOLDbutton,
themodeisswitchedtodigital,thenoneoftheassociated
LED’s lights up. Which one it is, depends on the last
selected digital operation.
Exception
Switching over from analog SINGLE mode to digital
mode sets the instrument automatically to digital
SINGLE mode.
Attention
The possibilities of delayed trace and the related
operations with delayed time base are not available in
digital mode.
Controls and readout

11
Subject to change without notice
For additional information regarding the digital mode, see
section STORAGE OPERATION.
HOLD
STORAGE MODE ONLY
Briefly pressing the STOR. ON / HOLD pushbutton
switches over between protected and unprotected mode
of the current memory contents.
Thecurrentcontentsofthememoryareprotectedagainst
overwriting when HLD (HOLD) instead of channel
information (e.g. Y1... ) is displayed in the readout. This
preventsachangeintheYtmodesetting,butitispossible
to select between DUAL (Yt) and XY display by pressing
the DUAL (22) pushbutton if one of these modes was
selected before activating HOLD.
If HOLD is switched off, one can observe how the
existing memory contents are successively overwritten
by new data especially with slow time base settings and
refresh mode. Protecting the memory contents in the
middle of a data acquisition process can result in an
irregularityat thejunctionofold (right)andnew data(left).
This can be avoided by recording in single shot mode
(SGL), even though the input signal is repetitive. At the
end of a sweep, one can use HOLD to protect the
contents against being overwritten by an unintentional
actuation of RESET (RES).
The signal in each of the current memory can be shifted
in the vertical direction (+/- 4cm) with the corresponding
Y-POS rotary knob when HOLD is operative.
The original trace position will be lost when shifted
vertically, but this can be found again. To this end the Y-
POS knob in question must be rotated quickly. Once the
original position is reached, the trace does not shift
anymore although the knob is rotated further.
Simultaneously a signal tone sounds. To shift the trace
verticallyagain itwill berequired tostoprotating theknob
for at least about 2 seconds.
Attention!
The dynamic range limits of the A/D converter may
become visible if a Y-position shift is performed after
storage. This can affect those signal parts which were
originally above or below the screen.
(8) PTR - Pushbutton for PRE and POST Trigger selection.
This function is not available in analog mode.
The PRETRIGGER function is used to capture signals that
occur prior to a trigger event, making the pre-history visible.
In contrast to this function, the POSTTRIGGER is used to
capture signals occurring after the trigger event, which
couldnotbecapturedin0%Pretrigger condition.Due tothe
dependence on trigger events, neither function is available
in the trigger independentmodes XYandROLL.The actual
PRE or POSTTRIGGER value is displayed by the readout
and changes, each time the PTR button is pressed, in the
following sequence: PT0%, PT25%, PT50%, PT75%,
PT100%, PT-75%, PT-50%, PT-25% and back to PT0%.
The values refer to the X-axis (graticule) of the screen
display (10% = 1div).
The following description assumes that the X magnifier
(x10) is inactive and the signal display starts on the
leftmost vertical graticule line. It is also assumed that a
trigger mode (source, coupling) is chosen, in which the
trigger point symbol is displayed. In contrast to analog
mode, using pre-trigger the trigger point symbol can be
shifted in X-direction.
PRETRIGGER
0% PRETRIGGER (readout “PT0%”) means that the
signal display starts with the trigger event. The trigger
point symbol indicates this position. If the X-POS. control
is not in center position, an arrow pointing to the left may
be displayed. Then the X-POS. control must be turned
clockwise until the arrow is no longer visible.
25% PRETRIGGER (readout “PT25%”) is achieved after
pressing the PTR button once. The signal display starts
with 25% pre-history and the trigger point symbol is
shifted 2.5 divisions to the right.
Each time the PTR button is pressed the PRETRIGGER
valueincreases by 25%until 100%is reached.If in100%
condition an arrow symbol is displayed in addition to the
trigger point symbol, the X-POS. control should be turned
ccw. to make the trigger point visible on the screen. The
duration of the prehistory is determined by multiplying
the time coefficient by the pretrigger value (in divisions).
E.g. 20ms/div x 7,5 div (= 75% pretrigger) = 150ms.
POSTTRIGGER
In POSTTRIGGER condition the trigger point is always to
theleftof thescreenandtherefore notvisible.Thetrigger
point symbol then only indicates the LEVEL setting. An
additionalarrowsymbolwhichpointstotheleftisdisplayed
to indicate post trigger operation. In POSTTRIGGER
condition the arrow symbol does not indicate a wrong X-
POS. setting. A minus sign (-) placed in front of the
percentage value, is displayed by the readout for
POSTTRIGGER mode indication.
Proceeding from 100% pre-trigger, the instrument swit-
ches over to 75% POSTTRIGGER (“PT-75%”) after the
PTR button is pressed. Then the trigger point is 7.5 div to
the left of the trace start on the screen. This means that
the signal capture starts 7.5 x time deflection coefficient
after the trigger event occurred.
Every time the PTR button is pressed the POSTTRIGGER
value changes in 25% steps until PTR-25% is active.
Whenthe PTRbuttonispressed again,bothpost andpre-
triggerareswitchedoffandthereadoutindicates“PT0%”.
Attention!
In time base settings from 100s/div to 50ms/div the pre-
or post-trigger is automatically switched off (“PT0%) if
refresh (RFR), envelope (ENV) or average (AVM) mode is
active. This is to avoid excessive waiting times.
Ifthepre-orpost-triggerfunctionisrequiredincombination
withthose timecoefficients, SINGLE (SGL)modeopera-
tion must be used.
(9) STOR. MODE - Pushbuttons with associated LEDs.
These functions are not available in analog mode.
Controls and readout

12 Subject to change without notice
If digital SINGLE (SGL) mode has not been chosen, one
of the associated LEDs is lit. The signal capture and
display mode can be selected by pressing one of the
buttons.Themodesettingisindicatedbyoneof the LEDs
(RFR, ENV, AVM and ROL) and also displayed by the
readout. The only exception is in XY storage mode. Then
the RFR-LED is lit and the readout displays XY. No other
signal capture and display mode can be chosen in XY
mode.ThedesiredYtsignalcapturemodecanbeselected
by pressing the upper or lower STOR. MODE button.
The following description presumes that HOLD (HLD) is
not activated and the trigger conditions are met.
(9) RFR - stands for refresh operation. In this mode, as in
analogmode,periodicallyrepeatingsignalscanbecaptured
and displayed.
The signal acquisition is started by triggering the digital
time base. Then the previously captured and displayed
signal will be overwritten with the current signal. This will
be displayed until the digital time base is triggered again.
This is in contrast to analog operation where the screen
remains blank when the time base is not triggered.
In refresh mode, the signal acquisition can be effected
with pre-triggering or post-triggering when a time base
between 20ms/cm and 1µs/cm is selected. The pre-
triggeringorpost-triggeringwillbeautomaticallyswitched
off (PT0%), with larger time coefficients (100s/cm to
50ms/cm) in order to avoid excessive waiting times. If it
is required to measure with pretrigger or post-trigger in
this time base range, one should select single shot
(SINGLE = SGL).
In XY digital mode the RFR-LED lights. It indicates a
continuous, trigger independent signal acquisition. The
trigger circuit is switched off.
(9) ENV - is the abbreviation for ENVELOPE operation.
In this mode the minimum and maximum values of the
signalduringseveralsignalacquisitionswillbedetermined
and displayed. Except for this display, the ENVELOPE
operation is identical to the refresh operation.
Changes in the signal are easier to measure and are more
visible in ENVELOPE operation. This is valid not only for
amplitude changes but also for frequency variations
(Jitter).
The ENVELOPE evaluation begins anew when the SIN-
GLE (10) button is pressed briefly, to actuate the RESET
(RES) function.
Attention!
The pretrigger or post-trigger will be automatically
switched off (PT0%) in the time base range from 100s/
cm to 50ms/cm.
(9) AVM - indicates Average (mean value) mode.
This operation is effective when the AVM-LED lights up
and the readout displays AV... .
In this case also several signal acquisition scans are
required; hence, it is similar to Refresh operation. The
signal is averaged over the several acquisitions so that
amplitudevariations(e.g. noise)andfrequencyvariations
(Jitter) are minimized or eliminated in the display.
The accuracy of the mean value evaluation increases as
the number the number of signal acquisition scans used
for evaluation is increased. One can select the number
between 2 and 512. The selected setting is displayed in
the readout. Of course, with increasing accuracy the
time required for this also increases.
Toselect adifferent valuebrieflypress bothSTOR. MODE
pushbuttons simultaneously. The AV... display in the
readout flashes indicating the setting mode. Now, the
valuecanbechangedbybrieflypressingtheupperorlower
STOR. MODE button. The setting mode can be exited by
againbriefly pressingthe twobuttons simultaneously.The
settingmodewillalsobeswitchedoffautomaticallyifnone
of the two buttons is actuated during about 10 seconds.
The averaging begins anew after briefly pressing the
SINGLE (10) pushbutton (RESET-function).
Attention!
The pretrigger or post-trigger will be automatically
switched off (PT0%) in the time base range from 100s/
cm to 50ms/cm.
(9) ROL - indicates ROLL mode.
In ROLLmodetheROL-LED is litandthereadoutdisplays
“ROL”.
In this mode, the memory contents and thus also the
signal display, are continuously updated. Because signal
capture is untriggered, no idle states arise while waiting
for a new trigger event to start signal capture. With each
signal sampling the new value is shown on the right-hand
edge of the screen, while the previously captured data
are shifted to the left. The leftmost value is shifted out of
the memory and lost.
Therecording canbestoppedat anytimeby selectingthe
HOLD (7) function.
ROLL mode can only be used with time coefficients from
100s/div to 50ms/div, as lower time coefficients (faster
time base speeds) are impractical.
If the time base is set to values between 20ms/div and
1µs/div and ROLL mode is selected, the time base will be
automatically set to 50ms/cm. The time deflection
coefficientsetpreviouslybeforeswitchingtoROLLmode
will be internally stored (e.g. 20ms/cm). If ROLL mode
has been selected inadvertently and the TIME/DIV.knob
hasnotbeenchanged,thetimebase willbe automatically
set to the internally stored coefficient when switching
from ROLL to AVERAGE mode.
(10) SINGLE - Pushbutton with two functions and associated
LEDs.
SINGLE
Pressing and holding the SINGLE pushbutton switches
between SINGLE and:
1.storage mode Yt (time base) or XY operation or
2.analog mode Yt (time base) operation,
dependent on the actual instrument setting.
Controls and readout

13
Subject to change without notice
In this operating mode a single signal acquisition process
or sweep can be started with a trigger, providing the
trigger circuit has been previously activated with RESET.
SINGLE automatically switches to normal triggering (NM
LED lights up). Otherwise the trigger automatic would
start the signal acquisition processes without an input
(trigger) signal.
STORAGE MODE ONLY
SINGLE mode is indicated by the SGL-LED (lit).
If the readout displays additionally the pre- or post-trigger
value (PT...),SINGLE mode in combination with Yt (time
base) storage mode is selected. In connection with XY
storagemodethe readoutdisplaysthe samplingrate(e.g.
40MS/s)and replaces thepre- orpost-trigger value(PT...)
by SGL.
When switched over to SGL, single signal acquisition is
in operation. The signal capture currently in progress and
not yet finished will not be terminated but continued to
the end.
Attention!
If SINGLE mode is present in combination with DUAL
mode, the minimum time coefficient is 5µs/div instead
of 1µs/div. Similarly if X-MAG. x10 is operative, then
500ns/div replaces 100ns/div.
ANALOG MODE ONLY
Selecting SINGLE mode switches the current sweep off
and blanks the screen.
SINGLE mode is indicated by the lighting SGL-LED and
thereadout displaying SGLnextto the/(SLOPE)symbol.
Two signals can be displayed during a single sweep only
when it is continuously switched between channel I and
channel II (chopper operation).
See DUAL (22) .
RESET (RES)
BrieflypressingtheSINGLEpushbuttoncausesaRESET.
The result depends on the current signal capture mode.
STORAGE MODE ONLY
A:
In combination with SINGLE, briefly pressing the SIN-
GLE pushbuttonactivates theRESET function.Thenboth
LEDs (SGL and RES) are lit. Whether the RES-LED
flashes once or is lit constantly, depends on:
1. the presence or absence of a trigger signal,
2. the selected time coefficient (time base) and
3. the pre- or post-trigger setting.
After the RESET function is switched on, the signal
acquisition will be effective at once if the HOLD function
is not active. If the pretrigger function is active, the
prehistory must elapse before the trigger event becomes
effective. The signal capture terminates with the trigger
event only with 100% pretrigger setting.
With all other pretrigger and post-trigger settings, the
signalacquisitionis notcompletewhenthe triggeroccurs
and will only be terminated later. After termination the
RES-LED extinguishes but the signal display remains.
BrieflypressingtheSINGLEpushbutton(RESETfunction)
again restarts a new single event capture which then
overwrites the previously recorded display.
Single events recorded in DUAL mode can also be
displayed in the XY mode when switched over to XY
operation.
Attention!
If time coefficients between 100s/div and 50ms/div are
present the signal acquisition becomes visible at once
as a ROLL display, but the signal acquisition has not-
hing to do with ROLL mode.
B:
BrieflypressingtheSINGLEpushbutton(RESETfunction)
is also effective if (instead of SINGLE)ENVELOPE or
AVERAGE mode is selected.
In both modes the evaluation / averaging begins anew.
ANALOG MODE ONLY
Capturing single events can also be carried out in analog
mode (e.g. photographing).
Briefly pressing the SINGLE pushbutton activates the
RES-LED in SINGLE mode. The next trigger event then
unblanks the beam and causes one time base sweep.
(11) REFERENCE - Pushbutton with 2 functions, associated
with 2 LED’s (only in Yt (time base) storage mode).
Theoscilloscopecontains2nonvolatilereferencememories.
One reference signal can be displayed together with the
actual signal. The contents of the reference memories are
not erased when the instrument is switched off.
The LEDs associated with the REFERENCE pushbutton
indicate the display of a reference signal and from its
origin. The reference signal is displayed in addition to the
actual signal. With the exception of DUAL mode, there is
no direct relationship between the reference memories (
I or II) and the channels (I or II).
Display
Briefly pressing the REFERENCE pushbutton switches
the reference indicator LEDs and consequently the signal
display in the following sequence:
reference memory off -
reference memory I -
reference memory II -
reference memory off.
Overwrite
After the reference memory has been selected (briefly
pressing) press and hold the REFERENCE pushbutton
until an acoustical signal indicates that the previously
stored reference signal has been overwritten by the
actual signal. During this procedure the instrument can
but must not be set to HOLD (HLD).
In DUAL mode only, REFERENCE memory I relates to
channel I and consequently REFERENCE memory II
relatestochannelII.Inthiscasetheoverwritingprocedure
Controls and readout

14 Subject to change without notice
must be performed twice. At first REFERENCE memory
I must be displayed and then overwritten. Then REFE-
RENCE memory II must be chosen and overwrittten.
Attention!
As the reference signal is stored and displayed in the
samepositionasthecurrentsignal,itisnotimmediately
noticeable in most cases.
(12) SAVE / RECALL - Pushbuttons.
The instrument contains 9 non volatile memories. These
can be used by the operator to save instrument settings
and to recall them. This relates to all controls which are
electronically selected.
SAVE
Press the SAVE pushbutton briefly to start the save
procedure. The readout then indicates the letter “S”
followed by a cipher between 1 and 9, indicating the
memory location. If the instrument settings stored in this
memory location must not be overwritten, briefly press
the SAVE or the RECALL pushbutton to select another
memory location. Each time the SAVE pushbutton is
briefly pressed the memory location cipher increases
until the location number 9 is reached. The RECALL
pushbutton function is similar but decreases the memory
locationcipher until 1is reached.
Pressandhold SAVEfor
approx.3secondstowritetheinstrumentssettingsinthe
memory.
RECALL
To recall a front panel setup, start that procedure by
briefly pressing the RECALL pushbutton. The readout
then indicates the letter “R” and the memory location
number.Ifrequired, selectadifferentmemory locationas
described above. Recall the settings by pressing and
holding the RECALL pushbutton for approx. 3 seconds.
Attention:
Make sure that the signal to be displayed is similar to
the one that was present when the settings were
stored. If the signal is different (frequency, amplitude)
to the one during storage then a distorted display may
result.
If the SAVE or the RECALL pushbutton was depressed
inadvertently, briefly press both pushbuttons at the same
time or wait approx. 10 seconds without pressing either
pushbutton to exit that function.
The setting controls and LED’s for the Y amplifiers,
modes,triggeringandtimebasearelocatedunderneath
the sector of the front panel described before.
(13) Y-POS. I - Control knob.
Thevertical tracepositionofchannel Icanbe setwiththis
control knob. In ADD (addition) mode both (Y-POS. I and
Y-POS. II) control knobs are active. If the instrument is
settoanalogXYmodethiscontrolknobisinactiveandthe
X-POS.knob must be used for a horizontal position shift.
If automatic triggering (AT)is present and the input is set
to GD (33), the vertical trace position corresponds with 0
Volt (reference) at the input and can be set to any suitable
position. In ADD mode these conditions apply to both
channels. After switching GD off and selecting DC input
coupling it is possible to determine the DC content of a
signal by comparing the actual Y position with the
previously determined 0 Volt Y position.
Y-POS. I Symbol
Providedthat thereadout is displayedand”DC REF = ON”
isselectedinthe”SETUP”submenu”MISCELLANEOUS”
the 0 Volt reference position is indicated by a ground ( )
symbol. For channel I this symbol is displayed on the left
of the vertical (graticule) center line, if the Y-POS. I trace
position is set within the screen. This allows you to
determine the 0 Volt reference position at any time.
Attention!
InXYmodethe0Voltreferencesymbol is automatically
switched off.
STORAGE MODE ONLY
In XY mode the Y-POS. I knob is operative as the X
position control and the X-POS. knob is inactive.
The Y-POS. I knob can be used for shifting the position
of a signal stored with HOLD.
Additional information
relating to this operation is described under HOLD (7)
.
(14) Y-POS. II - Control knob
The vertical trace position of channel II can be set with
this control knob. In ADD (addition) mode both (Y-POS. I
and Y-POS. II) control knobs are active.
If automatic triggering (AT)is present and the input is set
to GD (37), the vertical trace position corresponds with 0
Volt (reference) at the input and can be set to any suitable
position. In ADD mode these conditions apply to both
channels. After switching GD off and selecting DC input
coupling it is possible to determine the DC content of a
signal by comparing the actual Y position with the
previously determined 0 Volt Y position.
Y-POS. II Symbol
Provided that the readout is displayed and ”DC REF =
ON” is selected in the ”SETUP” submenu ”MISCEL-
LANEOUS” the 0 Volt reference position is indicated by
aground(⊥⊥
⊥⊥
⊥)symbol.ForchannelIIthissymbolisdisplayed
on the right of the vertical (graticule) center line, if the Y-
POS. IItrace position is set within the screen. This allows
you to determine the 0 Volt reference position at any
time.
Controls and readout

15
Subject to change without notice
Attention!
InXYmodethe0Voltreferencesymbol is automatically
switched off.
STORAGE MODE ONLY
The Y-POS. II knob can be used for shifting the position
of a signal stored with HOLD. Additional information
relating to this operation are described under HOLD (7).
(15) NM - AT - - Pushbutton with a double function and
associated NM-LED.
The following description assumes that Yt (time base)
mode has been chosen.
NM - AT selection
Press and hold the pushbutton to switch over from
automatic (peak value) to normal triggering (NM-LED
above the pushbutton lit) and vice versa. If the LED is
dark, automatic (peak value) triggering is selected.
Whether the peak value detection in automatic trigger
mode is automatically activated or not, depends on the
trigger coupling setting (TRIG.MODE (26)). The way the
trigger point symbol in the readout responds on different
LEVEL control knob settings indicates the situation:
1.If the trigger symbol can not be shifted in the vertical
direction when a signal is not applied or the signal height
is not sufficient, the peak value detection is active.
2.Under the condition that the trigger point symbol cannot
be shifted in such a way that it leaves the signal display
on the screen, the peak value detection is active.
3.The peak value detection is switched off if the trigger
point can be set outside the maximum peak values of
the signal, thus causing an untriggered signal display.
Slope selection
Briefly pressing this pushbutton selects which slope of
the signal is used for triggering the time base generator.
Each time this pushbutton is briefly pressed, the slope
direction switches from falling edge to rising edge and
vice versa. The current setting is displayed in the readout
by a slope symbol.
ANALOG MODE ONLY
The last setting in undelayed time base mode is stored
and still active if triggered DELAY (DTR)time base mode
isselected.Thisallowsforadifferent slopesetting forthe
triggered DELAY (DTR) time base mode.
(16) TR - Trigger indicator LED.
The TR LED is lit in Yt (time base) mode if the triggering
conditions are met. Whether the LED flashes or is lit
constantlydependsonthefrequencyof thetrigger signal.
(17) LEVEL - Control knob.
Turning the LEVEL knob causes a different trigger point
setting (voltage). The trigger unit starts the time base
when the edge of a trigger signal crosses the trigger
point. In most Yt modes the trigger point is displayed in
the readout by the symbol on the left vertical graticule
line. If the trigger point symbol would overwrite other
readout information or would be invisible when being set
above or below the screen, the symbol changes and an
arrow indicates in which vertical direction the trigger
point has left the screen.
The trigger point symbol is automatically switched off in
those modes where there is no direct relation between
the trigger signal and the displayed signal.
ANALOG MODE ONLY
The last setting in undelayed time base mode is stored
and still active if triggered DELAY (DTR)time base mode
is selected. This allows for a different level setting for the
triggered DELAY (DTR) time base mode.
STORAGE MODE ONLY
In storage mode the trigger point symbol also indicates
the post or pre-trigger condition by a horizontal position
shift.
Please note PTR (8) .
(18) X-POS. - Control knob.
This control knob enables an X position shift of the
signal(s) in Yt (time base) and analog XY mode. In
combination with X magnification x10 (Yt mode) this
function makes it possible to shift any part of the signal
on the screen.
STORAGE MODE ONLY
In XY mode the X-POS. knob is inoperative. The Y-POS.
I (13) must be used for X-position shift.
(19) X-MAG. x10 - Pushbutton and LED.
Eachtimethispushbuttonispressed thex10 LEDlocated
aboveis switchedon oroff. Ifthe x10LEDis lit,the signal
displayinallYt(timebase) modesis expanded10foldand
consequently only a tenth part of the signal curve is
visible. The interesting part of the signal can be made
visible with aid of the X-POS. (18) control. As the X
expansionresults inahigher timebasespeed (lowertime
deflection coefficient), all time and frequency relevant
information in the readout is switched over.
This pushbutton is not operative in XY mode.
ANALOG MODE ONLY
The expansion is 5 fold if the time base is set to 50ns/div.
Consequently the lowest time deflection coefficient is
10ns/div.
(20) VOLTS/DIV. - Control knob and associated LED.
This control knob for channel I has a double function. The
following description relates to the input attenuator
function (VAR-LED dark).
This control knob is operative in those modes where
channel I is active (CH I, DUAL, ADD and XY) and the
input coupling is not set to ground (GD (33)).
Controls and readout

16 Subject to change without notice
Turningthecontrolknobclockwiseincreasesthesensitivity
(decreases the deflection coefficient) in a 1-2-5 sequence
and decreases the sensitivity (increases the deflection
coefficient) if turned in the opposite direction (ccw.). The
available range is from 1mV/div up to 20V/div. The knob
isautomaticallyswitched inactiveifthechannelrelated to
it is switched off, or if the input coupling is set to GD
(ground).
The deflection coefficients and additional information
regardingtheactivechannel(s)aredisplayedinthereadout,
i.e. “Y1:...”deflection coefficient, input coupling” (”X:...”
in XY mode). The “:” symbolizes calibrated measuring
conditionsandisreplacedbythe“>”symbolinuncalibrated
conditions.
(21) CH I - VAR. - Pushbutton with several functions.
CH I
Briefly pressing the CH I button sets the instrument to
channel I (Mono CH I) mode. The deflection coefficient
displayed in the readout indicates the current conditions
(“Y1...”). If neither external nor line (mains) triggering
was active, the internal trigger source automatically
switches over to channel I (TRIG.-LED (23) CH Ilits). The
lastfunctionsettingoftheVOLTS/DIV (20)knobremains
unchanged.
All channel I related controls are active if the input (31) is
not set to GD (33).
VAR.
PressingandholdingthispushbuttonselectstheVOLTS/
DIV. (20) control knob function between attenuator and
vernier (variable). The current setting is displayed by the
VAR-LED located above the knob.
After switching the VAR-LED (20) on, the deflection
coefficient is still calibrated. Turning the VOLTS/DIV.
(20) control knob counter clockwise reduces the signal
height and the deflection coefficient becomes
uncalibrated.
The readout then displays i.e. “Y1>...” indicating the
uncalibrated condition instead of “Y1:...”. Pressing and
holding the CH I pushbutton again switches the LED off,
sets the deflection coefficient into calibrated condition
andactivatestheattenuatorfunction.Thepreviousvernier
setting will not be stored.
The CH I pushbutton can also be pressed simultaneously
with the DUAL (22) button.
Please note item (22).
(22) DUAL - XY - Pushbutton with multiple functions.
DUAL mode
Briefly pressing this button switches over to DUAL
mode. Both deflection coefficients are then displayed.
The previous trigger setting stays as it was, but can be
changed.
All controls related to both channels are active, if the
inputs (31) and (35) are not set to GD (33) (37).
Whether alternated or chopped channel switching is
present depends on the actual time base setting, and is
displayed in the readout.
ALT
displayed in the readout, indicates alternate channel
switching. After each time base sweep the instrument
internally switches over from channel I to channel II and
vice versa. This channel switching mode is automatically
selected if any time coefficient from 200µs/div to 50ns/
div is active.
CHP
indicates chopper mode, whereby the channel switching
occurs constantly between channel I and II during each
sweep. This channel switching mode occurs when any
time base setting between 500ms/div and 500µs/div has
beenchosen.Theactualchannelswitchingcanbechanged
to the opposite mode by briefly pressing both CH I (21)
and DUAL (22) simultaneously. If afterwards the time
coefficient is changed, the channel switching is
automatically set to the time coefficient related mode.
STORAGE MODE ONLY
The signal acquisition is carried out with both A/D
convertersinthetwochannel (DUAL)digitalmode.Since
there is no need to switch channels as in analog mode,
the readout display shows the signal acquisition mode
instead of ALT or CHP.
ADD mode
Addition mode can be selected by briefly pressing the
DUAL (22) and CH II (25) pushbuttons simultaneously.
Whether the algebraic sum (addition) or the difference
(subtraction) of both input signals is displayed, depends
on the phase relationship and the INV (37) setting. As a
result both signals are displayed as one signal.
For correct measurements the deflection coefficients for
both channels must be equal.
Please note “Operating
modes of the vertical amplifiers in Yt mode”.
The readout indicates this mode by a “+” sign located
between both channel deflection coefficients. While the
trigger mode is not affected, the trigger point symbol is
switched off.
The Y-position of the signal can be influenced by both Y-
POS controls (13) and (14).
XY mode
This mode can be switched on or off by pressing and
holding the DUAL button (22).
In XY mode the deflection coefficients are displayed as
“X...” for channel I and “Y...” for channel II, followed by
“XY”. Consequently INPUT CH I (31) serves as an X-
input and INPUT CH II (35) is used for Y-deflection. The
X-MAG x10 (19) function is automatically switched off.
The cursor lines may be active, but the trigger point and
the 0 Volt reference symbols are switched off.
Controls and readout

17
Subject to change without notice
ANALOG MODE ONLY
All trigger and time base related controls as well as the Y-
POS.I (13)knobaredeactivated.ForXpositionalteration,
the X-POS. (18) knob can be used.
STORAGE MODE ONLY
XY modeis indicatedbythe readoutdisplay ”XY”and the
RFR-LEDis lit. Noother STOR. MODE (9)can bechosen.
The readout displays the sampling rate (e.g. ”40MS/s”)
which can be selected by the TIME/DIV. (28) knob.
There are gaps in the display of Lissajous figures when
the sampling rate is too high. Too low a sampling rate can
result in a display which does not permit the frequency
ratio of the two signals to be determined. The selection
of a suitable sampling rate is simplified if both the signals
are first displayed in the refresh DUAL mode. The TIME/
DIV control should be then so set that at least one period
ofeachsignalisdisplayed.Afterthisonecanswitchtothe
XY Digital mode.
Attention!
Note the following differences compared to the analog
XY mode:
The YPOS.I (13) controlfunctionsasX-Positioncontrol
and the X-POS (18) control is disabled.
(23) TRIG. - Pushbutton with double function for trigger
source selection and associated LEDs.
The button and the LEDs are deactivated if line (mains)
triggering is selected or XY operation is chosen. In the
latter case this also applies to all trigger related controls
and LEDs.
With the aid of this button, the trigger source can be
chosen. There are three trigger sources available:
channel I,
channel II (both designated as internal trigger sources)
and the TRIG. EXT. (33) input for external triggering.
The availability of the internal sources depends on the
actual channel mode. The actual setting is indicated by
the associated LED(s).
Briefly pressing the button switches over in the following
sequence:
I - II - EXT - I in DUAL and ADD (addition) mode,
I - EXT - I if mono channel I is present,
II - EXT - II under mono channel II conditions.
EachconditionisindicatedbytheassociatedLED.Thetrigger
point symbol is switched off in external trigger condition.
STORAGE MODE ONLY
In combination with ROLL mode, all controls and LEDs
regarding trigger functions are disabled.
ALT:
Pressingandholdingthebuttonselectsalternatetriggering
in DUAL mode. Under these conditions both TRIG CH I
and CH II LEDs are lit. As alternate triggering requires
alternate channel operation, alternate channel switching
isset automatically.A changeof thetimecoefficient then
has no affect regarding the channel switching mode. In
addition to the deflection coefficients display, “ALT” is
displayed by the readout instead of “CHP”.
In alternate trigger mode the trigger point symbol is
switched off.
Alternate triggering is not available or automatically
switched off under the following conditions:
ADD (addition) mode,
TVL,TVF and line (mains) trigger coupling and the time
base modes which are available only in analog mode
(search (SEA),delayed (DEL and DTR)).
(24) VOLTS/DIV. - Control knob and associated LED.
Thiscontrol knobfor channelII hasa doublefunction. The
following description relates to the input attenuator
function (VAR-LED dark).
This control knob is operative in those modes where
channel II is active (CH II,DUAL,ADD and XY) and the
input coupling is not set to ground (GD (37)).
Turningthe control knobclockwise increasesthe sensitivity
(decreases the deflection coefficient) in a 1-2-5 sequence
and decreases the sensitivity (increases the deflection
coefficient) if turned in the opposite direction (ccw.). The
available range is from 1mV/div up to 20V/div. The knob is
automatically switched inactive if the channel related to it is
switched off, or if the input coupling is set to GD (ground).
The deflection coefficients and additional information
regarding the active channel(s) are displayed in the readout,
i.e. “Y2:...”deflection coefficient, input coupling” (”Y:...” in
XY mode). The “:” symbolizes calibrated measuring
conditionsandisreplacedbythe “>”symbolinuncalibrated
conditions.
(25) CH II - VAR. - Pushbutton with several functions.
CH II
Briefly pressing the CH I button sets the instrument to
channel II (Mono CH I) mode. The deflection coefficient
displayed in the readout indicates the current conditions
(“Y2...”). If neither external nor line (mains) triggering
was active, the internal trigger source automatically
switchesover tochannel II(TRIG.-LED (23) CH Ilits).The
lastfunctionsettingoftheVOLTS/DIV(24)knobremains
unchanged.
All channel I related controls are active if the input (35) is
not set to GD (37).
VAR.
PressingandholdingthispushbuttonselectstheVOLTS/
DIV. (24) control knob function between attenuator and
Controls and readout

18 Subject to change without notice
vernier (variable). The current setting is displayed by the
VAR-LED located above the knob. After switching the
VAR-LED (24) on, the deflection coefficient is still
calibrated. Turning the VOLTS/DIV. (24) control knob
counter clockwise reduces the signal height and the
deflection coefficient becomes uncalibrated.
The readout then displays i.e. “Y2>...” indicating the
uncalibrated condition instead of “Y2:...”. Pressing and
holding the CH II pushbutton again switches the LED off,
sets the deflection coefficient into calibrated condition
andactivatestheattenuatorfunction.Thepreviousvernier
setting will not be stored.
The CH IIpushbuttoncan alsobe pressedsimultaneously
with the DUAL(22) button.
Please note item (22) .
(26) TRIG. MODE
Pushbuttons and associated indicator LEDs.
Pressing the upper or lower button selects the trigger
coupling. The actual setting is indicated by a TRIG.
MODE-LED (26).
Each time the lower TRIG. MODEpushbutton is pressed
the trigger coupling changes in the sequence:
AC DC content suppressed,
DC DCcontenteffective(peakvaluedetectioninactive),
HF high-pass filter cuts off frequencies below
approx. 50kHz (trigger point symbol switched off),
LF low-pass filter cuts off frequencies above
approx. 1.5kHz, in combination with automatic
triggering AC or normal triggering DC coupled,
TVL TV signal, line pulse triggering,
trigger point symbol switched off,
TVF TV signal, frame pulse triggering,
trigger point symbol switched off.
~line/mains triggering, trigger point symbol
and TRIG. LED (23) are switched off.
In some trigger modes such as alternate triggering, some
trigger coupling modes are automatically disabled and
can not be selected.
(27) DEL.POS.
Rotary knob with two functions and related HO-LED.
The DEL.POS. knob functions as a hold off time control,
whenthe timebaseis notworkingin theSEA. (SEARCH)
orin DEL. (DELAY)mode. TheHO-LEDis not litwhenthe
holdofftimeissettominimum.TheHO-LEDlightsupand
theholdofftimeincreasesastheknobisrotatedclockwise.
A signal sounds on reaching the maximum hold off time.
Similarly in the opposite direction until minimum hold off
time is reached (HO-LED extinguishes). The hold off time
is automatically set to minimum when the time base is
changed. (For the application of hold off time setting see
the paragraph with the same heading).
The start of the trace can be set with the DEL.POS.
control in the time base modes SEA. (SEARCH) or DEL.
(DELAY).
See SEA. / DEL. - ON / OFF (29).
STORAGE MODE ONLY
The DEL.POS. control and the HO-LED are disabled,
since in this mode the hold off time is set to minimum.
The hold off time last used in the analog mode is not
saved. Consequently, the hold off time is set to minimum
when it is switched back to analog mode.
The DEL.POS. control cannot be used for delay setting
since neither SEA. (SEARCH) nor DEL. (DELAY) time
base operation is available.
(28) TIME/DIV. - Control knob.
The time base is set with this knob in the TIME/DIV. field,
and the setting is displayed at the top left in the readout
(e.g. ”T:10µs”). This knob acts as the time base step
switch when the VAR-LED above it is not lit. Then, the
time deflection coefficient can be set in a 1-2-5 sequence
and the time base is calibrated. Rotating anticlockwise
increasesthedeflectioncoefficientand rotatingclockwise
decreases the deflection. The control acts as a vernier
(fine adjustment) when the VAR-LED is lit.
The following description refers to the function as a time
base switch.
Attention
The different deflection coefficient ranges between the
analog and digital time bases require special conside-
ration when switching between analog and digital
modes. These are described in section (7).
ANALOG MODE ONLY
Time deflection coefficients between 500ms/div. and
50ns/div. in a 1-2-5 sequence can be selected without X-
MAG.x10 magnification.Timedelaybetween 120msand
200ns can be selected in the ”SEA” (SEARCH) mode.
Time deflection coefficient range in the ”DEL” (DELAY)
mode extends from 20ms/div. to 50ns/div.
STORAGE MODE ONLY
The time base can be set to deflection coefficients
between 100s/div. and 1µs/div in storage mode, if X-
MAG x10 is inactive.
(29) SEA./DEL. - ON/OFF pushbutton
The pushbutton is operative only in analog mode.
Thisbuttonisusedtoswitchbetweendelayedandundelayed
time base. The delayed time base operation enables a
magnified display in X-direction which is otherwise only
possible with a second time base. Pressing and holding the
button switches from normal time base mode to SEA.
(SEARCH), when currently neither ”SEA” (SEARCH) nor
”DEL” (DELAY) operation or ”DTR” (triggered DELAY) is
effective.Afterwards,itcanbeswitchedbetween SEA.and
DEL. by briefly pressing the button.
Theseoperatingmodesareindicatedinthe readoutto the
right of the trigger slope indication thus:
In case of SEARCH , ”SEA” will be displayed;
In untriggered DELAY mode, ”DEL” (DEL.) and
in triggered DELAY mode, ”DTR” (DEL.TRIG.).
Controls and readout

19
Subject to change without notice
Noneofthesewillappearinthereadoutinundelayedtime
base operation.
When”SEA”,”DEL”or”DTR”modeiseffective,pressing
and holding the button switches over to undelayed time
base.
Provided that neither ”SEA” nor ”DEL” resp. ”DTR” are
active, the following description assumes that:
1.X-MAG. x10 is switched off,
2.the trace starts on the left vertical graticule line and
3.the part of signal to be expanded must be displayed
within the (horizontal) range 2 up to 6 divisions after
trace start position.
SEA
In SEA.(SEARCH)mode,theholdofftimeisautomatically
set to minimum and for the first few divisions the trace
is blanked. The trace will then be unblanked. The point at
which the trace starts can be varied with DEL.POS (fine
adjustment) from about 2 to 6 divisions. The blanked
sectionservesasaguidetothedelaytime.Thedelaytime
is based on the current time deflection coefficient setting
and can also be coarsely set with the TIME/DIV control
(range: 20ms to 100ns).
DEL
Pressing the button briefly switches over from ”SEA” to
”DEL” (DELAY) mode. Now the trace starts at the left
vertical graticule line, beginning with that part of the
signal that was previously unblanked first when ”SEA”
was active. From that position, the signal display can be
expanded in the X-direction by rotating the TIME/DIV
controlclockwiseandthusdecreasingthetimedeflection
coefficient. If a part of the signal of interest goes beyond
the right edge, it can be brought within the screen and
made visible by DEL.POS knob. Increasing the time
deflection coefficient beyond that used in the ”SEA”
(SEARCH) mode is not possible.
In the untriggered ”DEL” (DELAY) mode, a trigger event
does not start the trace at once but only starts the delay
time.Afterthedelaytime haselapsedthetraceisstarted.
DTR
In triggered DELAY mode (DTR), to start the sweep, a
signal suitable for triggering must appear after the delay
time. The trace will be started if the instrument settings
(e.g. LEVEL setting) enable a triggering.
See DEL.TRIG.
- VAR. (30) .
(30) DEL.TRIG. - VAR. - Pushbutton with two functions
The pushbutton is operative only in analog mode.
In the case of untriggered ”DEL” (DELAY) mode (29),
briefly pressing the button switches over to ”DTR”
(triggered DELAY mode). Thereby, the previously active
settings, Automatic/normal triggering (15), trigger
LEVEL (17),trigger slope (15) and trigger coupling
(26) will be stored.
The instrument will be automatically switched to normal
triggering (NM) and DC trigger coupling in ”DTR” mode.
Subsequently the trigger LEVEL setting and the trigger
slope should be so adjusted that the signal for delayed
trigger can trigger the time base. Without triggering the
screen will remain blank.
Briefly pressing the button again switches back to
(untriggered) DEL. operation.
VAR.
Pressingandholdingthepushbuttonchangesthefunction
of the TIME/DIV. knob.
TheTIME/DIV.knob (28)canfunctionasatimedeflection
coefficient switch (1-2-5 sequence) or as a time vernier
(fine adjustment). The current function is indicated by the
VAR-LED. The TIME/DIV. knob functions as a vernier
when the VAR-LED is switched on, but the time base
setting remains calibrated until the (vernier) knob is
operated. The readout now indicates ”T>...” instead of
”T:...”.Rotating further anticlockwise increases the time
deflection coefficient (uncalibrated) until the maximum is
reachedindicated bya beep.Rotating theknobclockwise
has the opposite effect. Now, the vernier is again in the
calibrated position and the symbol ” >” will be replaced
by symbol ” :”.
The function of the knob can be switched back to normal
(calibrated) time base, pressing and holding the button.
Underneath the front panel sector described above, the
BNC sockets and four pushbuttons are located.
(31) INPUT CH I - (HOR. INP. (X)) - BNC socket.
This BNC socket is the signal input for channel I (INPUT
CH I). In XY mode, signals at this input are used for the X-
deflection. The outer (ground) connection is galvanically
connected to the instrument ground and consequently to
the safety earth contact of the line/mains plug.
(32) AC / DC - Pushbutton with two functions.
Input coupling:
Briefly pressing this pushbutton switches over from AC
(~symbol)to DC(=symbol)inputcouplingandviceversa,
iftheinput isnotswitchedtoGD (33).TheAC/DC setting
is displayed in the readout with the deflection coefficient.
Probe factor:
Pressingandholdingthepushbuttonselectstheindicated
deflectioncoefficientofchannelIdisplayedinthereadout,
between 1:1 and 10:1. In condition 10:1 the probe factor
is thus indicated by a probe symbol displayed by the
readout in front the channel information (e.g. “probe
symbol”,Y1...). In the case of cursor voltage measu-
rement, the probe factor is automatically included.
Controls and readout

20 Subject to change without notice
Please note:
The probe symbol should not be activated unless a x10
(10:1) attenuator probe is used.
(33) GD - Pushbutton
Each time this pushbutton is pressed briefly, the input is
switched from active to inactive and vice versa. It is
displayed in the readout as an earth (ground) symbol
instead of the deflection coefficient and the ~ (AC) or =
(DC) symbol.
The GD setting disables the input signal, the AC/DC (32)
pushbutton and the VOLTS/DIV (20) knob. In automatic
triggermode theundeflected traceis visiblerepresenting
the 0 Volt trace position.
See Y-POS. I (13).
(34) Ground socket
4mm banana socket galvanically connected to safety
earth.
Thissocketcanbeusedasreferencepotentialconnection
for DC and low frequency signal measurement purposes
and in COMPONENT TEST mode.
(35) INPUT CH II - BNC socket.
This BNC socket is the signal input for channel II (INPUT
CH II). In XY mode, signals at this input are used for the
Y-deflection.Theouter(ground)connectionisgalvanically
connected to the instrument ground and consequently to
the safety earth contact of the line/mains plug.
(36) AC / DC - Pushbutton with two functions.
Input coupling:
Briefly pressing this pushbutton switches over from AC
(~symbol)to DC(=symbol)inputcouplingandviceversa,
iftheinput isnotswitchedtoGD (37).TheAC/DC setting
is displayed in the readout with the deflection coefficient.
Probe factor:
Pressingandholdingthepushbuttonselectstheindicated
deflectioncoefficientofchannelIIdisplayedinthereadout,
between 1:1 and 10:1. In condition 10:1 the probe factor
is thus indicated by a probe symbol displayed by the
readout in front the channel information (e.g. “probe
symbol”,Y2...). In the case of cursor voltage measu-
rement, the probe factor is automatically included.
Please note:
The probe symbol should not be activated unless a x10
(10:1) attenuator probe is used.
(37) GD - INV. - Pushbutton with two functions.
GD
Each time this pushbutton is pressed briefly, the input is
switched from active to inactive and vice versa. It is
displayed in the readout as an earth (ground) symbol
instead of the deflection coefficient and the ~ (AC) or =
(DC) symbol.
The GD setting disables the input signal, the AC/DC (36)
pushbutton and the VOLTS/DIV (24) knob. In automatic
triggermode theundeflected traceis visiblerepresenting
the 0 Volt trace position.
See Y-POS. II (14).
INV.
Pressingandholdingthispushbuttonswitchesthechannel
IIinvert(INV.)functiononoroff. Theinvert “on”condition
is indicated by the readout with a horizontal bar above
“Y2” (Yt mode) or ”Y” (XY mode). The invert function
causes the signal display of channel II to be inverted by
180°.
(38) TRIG. EXT. / INPUT (Z)-BNC socketwith twofunctions.
The outer (ground) connection is galvanically connected
to the instrument ground and consequently to the safety
earthcontact ofthe line/mainsplug.The inputimpedance
is approx. 1MΩII 20pF.
TRIG. EXT.
This BNC socket is the external trigger signal input, if
external triggering is selected. Briefly pressing the TRIG.
(23) pushbutton, until the TRIG. “EXT” -LED (23) is lit,
switches the external trigger input active.
The trigger coupling depends on the TRIG. MODE (26)
setting.
ANALOG MODE ONLY
Z- Input
IfneitherCOMPONENTTESTnorexternaltriggercoupling
(TRIG. EXT.) is chosen, the socket is operative as a Z
(trace intensity modulation) input.
High TTL level (positive logic) effects blanking, low level
gives unblanking. No higher voltages than +5 Volt are
permitted.
Belowthe CRTthereare thecontrolsforthereadout, the
component tester and the squarewave calibrator with
their outputs.
Please note:
The following description of the cursor related controls
assumes that the readout is visible and the component
tester is switched off.
(39) PRINT / MENU - Pushbutton with 2 functions.
STORAGE MODE ONLY
PRINT
Briefly pressing the pushbutton starts a documentation
(hardcopy) if the following preconditions are met:
1.The oscilloscope must be connected to the external
HAMEG interface HO79-6.
2.The software version installed in HO79-6should not be
< V2.00.
The device used for documentation (e.g. printer, plotter)
must be connected with one of the HO79-6 ports. The
documentation includes the signal display, the graticule,
the measurement parameters and additional information
such as oscilloscope type and HO79-6 software version.
Controls and readout