As A Single Function Generator - Promax GF-941 Manual De Instrucciones

USER'S MANUAL GF-941
4.3.1

As a single function generator

To use the GF-941 as a three-basic function generator, the desired frequency shall
be selected at first. This frequency issues from combination of two controls: the range
selector [1] and the frequency variable control [2]. The obtained value will appear on the
frequency indicator [3].
Note that because indicator [3] is not a frequency direct meter, but a digital indicator
of control [2] position, providing a readout equivalent to the obtained frequency.
Second, the desired function will be achieved by pressing one of the three selectors
[4], getting a square, triangular or sine signal, respectively.
Signal is obtained on output [14] and signal amplitude is obtained combining the
variable control [10] and step attenuator [11] so that, bearing in mind that the generator
highest output is 20 Vpp in open circuit, to obtain a 2 Vpp signal it will be enough to keep
the AMPLITUDE control in the maximum position and press the 20 dB attenuator [11].
Attenuations achieved by selector [11] will be the result of value additions of driven keys.
In regard with the output itself, account is to be taken that generator output
impedance is 50 Ω, so in order to avoid deformations that are likely to be caused by the
cable connected to the output, this cable shall have a specified impedance of the same
value, and shall be loaded with that impedance on its terminal end. This is essentially
important on high frequencies, or what is the same, fast signal transitions.
WARNING: NEVER
CONNECTOR, AS UNIT MAY BE DAMAGED.
1.- DC offset use
The selected signal can be overlapped to a direct voltage settled previously through
the DC OFFSET control [12]. It is enough for to remove that control from position OFF.
In such a way, voltage can be changed from 0 to 10 V (open circuit) and +/- polarity
picked through selector [13].
When using this possibility, take care that peak voltage plus overlapped direct voltage
do not exceed 10 V in open circuit or 5 V over 50 Ω, as undesirable clippings or
distortions would appear on signal.
2.- Variable symmetry use
Output signal will be symmetrical in regard with time when selector [5] is on rest
position and then, control VARIABLE [6] will be inoperative. If, for instance, a signal
asymmetry is desired to obtain a slope or pulses from the triangular or square signal,
respectively, it will be sufficient to drive control VARIABLE [6] by pressing selector
SYMM. [5]. In such conditions, VARIABLE control will bid an output symmetrical signal
on its middle position approximately. This signal may be varied in a steady way in
either direction up to the maximum specified.
04/2003
APPLY AN EXTERNAL VOLTAGE TO THE OUTPUT
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