Subject to change without notice
9
H
between 0.5 and 8div., if possible 3.2 to 8div.,
U
between 1mV
pp
and 160V
pp
,
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
= 0.05·4.6 =
0.23V
pp
.
Input voltage
U
= 5V
pp
,
set deflection coefficient
D
= 1V/div.,
required display height H
= 5:1 =
5div
.
Signal voltage U = 230V
rms
·2
√
2 = 651V
pp
(voltage > 160V
pp
, with probe 10:1:
U
= 65.1V
pp
),
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.
The input voltage must not exceed 400V, indepen-
dent 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 or –400V.
So for AC voltages with a mean value of zero volt the
maximum peak to peak value is 800V
pp
.
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 1M
Ω
input resistor of the
oscilloscope, which are disabled by the AC input coupling
capacity when AC coupling is selected. This also 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 signal frequency. For sinewave signals with
frequencies higher than 40Hz this influence is negligible.
In the GD (ground coupling) setting, the signal path is
interrupted directly beyond the input. This causes the
attenuator to be disabled again, but now for both DC and
AC voltages.
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 1200V
pp
. The 100:1
probe HZ53 allows for 1200V DC or 2400V
pp
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 displayed on the oscilloscope, a normal x10 probe is
sufficient. In this case, an appropriate high voltage capacitor
(approx. 22-68nF) must be connected in series with the
input tip of the probe.
Total value of input voltage
The dotted line shows a voltage alternating at zero volt level. If super-
imposed on a DC voltage, the addition of the positive peak and the DC
voltage results in the max. voltage (DC + AC
peak
).
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 horizontal central line according to
whether positive and/or negative deviations from the
ground potential are to be measured.
Time Measurements
As a rule, most signals to be displayed are periodically
repeating processes, also called periods. The number of
periods per second is the repetition frequency. Depending
on the time base setting of the
TIME/DIV.
switch, one or
several signal periods or only a part of a period can be
displayed. The time coefficients are stated in
s/div.
,
ms/
div.
and
µs/div.
on the
TIME/DIV.
-switch. The scale is
accordingly divided into three fields.
The duration of a signal period or a part of it is
determined by multiplying the relevant time (hori-
zontal distance in div.) by the time coefficient set on
the TIME/DIV.-switch.
The variable time control (identified with an arrow
knob cap) must be in its calibrated position CAL.
(arrow pointing horizontally to the right).
With the designations
L
= displayed wave
length in div.
of one period,
T
=
time in seconds
for one period,
F
= recurrence
frequency in Hz
of the signal,
T
c
=
time coefficient in s/div.
on timebase switch and
the relation
F = 1/T
, the following equations can be stated:
With depressed X-MAG. (x10) pushbutton the T
c
value must be divided by 10.
However, these four values are not freely selectable.
They have to be within the following limits:
L
between 0.2 and 10div., if possible 4 to 10div.,
T
between 0.01µs and 2s,
F
between 0.5Hz and 30MHz,
T
c
between 0.1µs/div. and 0.2s/div. in 1-2-5 sequence
(with
X-MAG. (x10)
in out position), and
T
c
between 10ns/div. and 20ms/div. in 1-2-5 sequence
(with pushed
X-MAG. (x10)
pushbutton).
DC + AC
peak
= 400V
max.
DC
AC
time
DC
peak
AC
Voltage
T
T
c
L =
T
L
T
c
=
T = L · T
c
L =
1
F · T
c
1
L · T
c
F =
T
c
=
1
L · F
