Function Selection; Trigger Output; Frequency Adjustment; Output Amplitude And Signal Connection - Hameg HM8030-5 Handbuch

Function selection

The type of output signal is selected with the
function selection switch (6). A total number of 3
different waveforms - sine, square and triangle -
are available. The functions are marked with the
corresponding symbols. If the "ON" pushbutton
(8) is activated a DC voltage level is supplied by
the HM8030-5 or supperimposed on the output
signal.

Frequency adjustment

Coarse adjustment is performed with the range
keys. The desired frequency is selected by turning
the FREQUENCY control (3). The selected
frequency appears on the 4-digit display (1).
Compared to knob scales, this display has a much
higher resolution.
Output amplitude and signal
connection
Adaptation in decade steps to the desired
amplitude 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 (12), the maximum attenuation
amounts to - 60dB. With the maximum amplitude
of 10Vpp, the minimum signal voltage to be
supplied is about 10mV. These values are obtained
when the generator output is terminated with 50Ω.
In the open-circuit condition, the available signal
amplitude is twice as high. Therefore the
maximum output voltage of the output socket is
specified with 20Vpp. If exact square-shaped
signals are required, care should be taken that only
50Ω coaxial cables (e.g. HZ34) are used. Further-
more, this cable must be terminated with a 50Ω
through-termination (e.g. HZ22). If these
precautions are not observed, over shoot may
occur, 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 used terminating resistor must
dissipate the corresponding effective power.
The output terminal of the HM8030-5 is
short circuit proof. However, if an
external DC voltage exceeding ±45V is
applied to the output, the output stage is
likely to destruction. It can withstand DC
voltage up to ±45V for a time of max. 30
seconds.
If the output of the HM8030-5 unit comes into
contact with components of the circuit under test,
which are carrying DC voltage, an isolationg
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
16
affected over the whole frequency range of the H
M 8030-5 unit.

Trigger output

In the sine, square and triangle modes, the
trigger output (7) supplies a square signal in
synchronism with the output signal. An offset
voltage adjusted at the 50Ω output has no influence
upon the trigger signal. The trigger output is short-
circuit-proof and can drive several TTL inputs.
Sweep facilities
1)Internal sweep
The internal sweep facility of the HM8030-5
allows checking of filters and equipment in the
frequency range from 3Hz to 5MHz. Operation is
very easy and is confined to the setting of start
and stop frequency and sweep time. Activation is
by simply pressing the SWEEP push button.
Sweep can be combined with all available
functions on the HM8030-5. The Start-frequency
is automatically given by the settings of the range
selector and the frequency dial and is shown on
the 4-digit display. It can be set to any frequency
in the entire frequency range of the HM 8030-5.
The stop frequency can be independently set the
same way to a frequency which is a maximum of
2 decades appart from the start frequency. The
max. sweep range is up to a factor of approx.100.
The sweep time can be set when TIME is selected
by means of the SWEEP button. The sweep starts
immediately when TIME is selected and can be
set during operation. Time is set by means of the
FREQUENCY potentiometer (3) and ranges from
20ms to 15s. For external wobbulation please refer
to "FM input".
2) FM input
If a positive DC voltage is applied to the FM
input on the rear panel of the HM8001-2, the
generator frequency increases and is accordingly
displayed. A negative DC voltage reduces the
frequency. The frequency displacement depends
on the value and polarityof the DC voltage U and
on the FREQUENCY setting. The setfrequency
N (DC voltage not included) can be selected at
0
will.
Computation: N = N
N = digit display without voltage U
0
N = digit display including voltage U,
U = ± voltage at the FM input.
A = 855 (digits per volt),
It should be noted that only the displayed digits
are valid; the decimal point is not taken into
consideration (e.g. 100.0 ≡ 1000 digit). The max.
frequency (3 MHz) cannot and "000" should not
be exceeded. Any zeroes preceding the decimal
point are dropped.
Limits: if the highest displayed number is N =
5000 and the smallest N
3.6V max. The frequency increases by a factor of
10 . If the smallest displayed number is N = 50
(lower numbers are possible, but inaccurate) and
Änderungen vorbehalten / Subject to change without notice
+ A ⋅ ⋅ ⋅ ⋅ ⋅ U or U = (N-N
0
= 500, then U will be +
0
) : A
0