Functions; Function Selection; Frequency Adjustment; Trigger Output - Hameg Instruments HM8030-6 Mode D'emploi

Functions

Function selection

The type of output signal is selected with the
function selection switch
4 different waveforms (sine, square, triangle and
pulse) are available. The functions are marked
with the corresponding symbols. If the ON-
pushbutton is activated a DC voltage level is
supplied by the HM8030-6 (all function LEDs
off) or superimposed on the output signal, except
in pulse mode.
The max. offset voltage is ±5 V with open outputs
and is continuously adjustable with the OFFSET
control .
In pulse mode no offset voltage is available. With
control pulse width is continuously adjustable
from 10% to 90%. In postition OFF of pushbutton
a fi xed pulse width of 50% is delivered.

Frequency adjustment

Coarse adjustment is performed with the range
keys . The desired frequency is selected by
turning the FREQUENCY control
frequency appears on the 5-digit display
Output amplitude and signal connection
Adaptation in decade steps to the desired am-
plitude range is performed by the use of two
attenuators with –20 dB each, which are activated
by pushbuttons .
Including the continuously adjustable AMPLI-
TUDE control , the maximum attenuation
amounts to –60dB. With the maximum amplitude
of 10V , the minimum signal voltage to be sup-
pp
plied is about 10mV. These values are obtained
when the generator output is terminated into
50Ω. In the open-circuit condition, the available
signal amplitude is twice as high. Therefore the
maximum output voltage of the output socket
is specifi ed with 20V
pp
signals are required, care should be taken that
only 50Ω coaxial cables (e.g. HZ34) are used.
Furthermore, this cable must be terminated into a
50Ω through-termination (e.g. HZ22). If these pre-
cautions are not observed, overshoot may occur,
. A total number of
. The selected
.
. If exact square-shaped
especially when high frequencies are selected. If
test circuits having a 50Ω input impedance are
connected, this termination is not required. In
high signal voltage ranges, it should be noted that
the terminating resistor used must be specifi ed
for the power dissipated.
The output terminal of the HM8030-6 is short
circuit proof. However, if an external DC-volta-
ge exceeding ±45 V is applied to the output, the
output stage is likely to be destructed. It can
withstand DC-voltage up to ±45 V for a time of
max. 30 seconds.
If the output of the HM8030-6 unit comes into
contact with components of the circuit under
test, which are carrying DC voltage, an isolati-
on capacitor of appropriate dielectric strength
should be connected in series with the output of
the generator. The capacitance of this isolating
capacitor should be selected in that way that the
frequency response of the output signal is not
affected over the whole frequency range of the
HM 8030-6 unit.

Trigger output

In the sine, square and triangle modes, the trigger
output supplies a square signal in synchronism
with the output signal. An offset voltage adjusted at
the 50Ω output has no infl uence upon the trigger
signal. The trigger output is short-circuit-proof
and can drive several TTL inputs. If the trigger
output is terminated into 50Ω, the trigger level
will fall below TTL specifi cations. Therefore short
or low-capacity cables without a 50Ω termination
are to be used.

Sweep facilities

st
1 Internal sweep
The internal sweep facility of the HM8030-6
allows checking of fi lters and equipment in the
frequency range from 3Hz to 10 MHz. Operation
is very easy and does not require more than
setting of the start and stop frequencies and
the sweep time. Activation is by simply pressing
the SWEEP-pushbutton
Sweep can be combined with all available func-
tions on the HM8030-6. The start frequency is
automatically given by the settings of the range
selector and the frequency dial
shown on the 5-digit display. It can be set to any
Subject to change without notice
F u n c t i o n s
(START-LED lights) .
and is
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