USER'S MANUAL GF-941
To select this function, press control SWP [17] and let both AM and FM controls off.
Then, function selectors [17] remains inoperative as, in any case, the auxiliary generator
will supply a linear ramp signal to produce a sweep.
Select sweep recurrent frequency with frequency controls [15] and [16], described in
item 4.3.2.1.
Then, select end or highest sweep frequency through controls [1], [2] and [3], like a
function mode without sweep. Subsequently, origin or start sweep frequency will be given
by control [8] position.
The lowest frequency value, if this is to be known
obtained at the main generator output [14] in a continuous way, with the three frequency
selectors [15] in rest position (depressed), while control [8] gets still operative.
Do remark that in order to achieve sweeps in a regular way, sweep recurrent
frequency shall be considerably lower than those wanted to be achieved on sweeping.
Symmetry control [18] is still active on the SWP function, in which this control will
operate increasing the sweep flyback time, while keeping sweep time constant.
In this function, output [19] refers to the signal that produces a sawtooth sweep.
This signal can be used as an horizontal sweep signal for the oscilloscope used to test the
circuit response.
Main generator TRIGGER control may be used to cancel signal during sweep
return. Refer to use as a triggered or burst generator, on next item.
4.3.4
As a triggered or burst generator
For various analysis sorts, as transitory responses for instance, burst or trigger
shaped signals are useful, in which signal is supplied only for a given time with a
determined recurrent time between bursts and void signal between them.
The GF-941 generator supplies a main generator triggered signal when TRIGGER
control is in any position but OFF. This control will allow trigger to start at a specified point
or phase angle of main generator. Burst end is determined by the auxiliary generator
recurrent frequency, in such a way that stopping is carried out on the same main signal
phase that the start triggering. To bring this about when getting the auxiliary signal state
that determines the end of burst, this burst will keep on until it reaches an identical phase to
the starting one.
There is a particular case of triggering form, in which SINGLE/REPET selector [25]
of rear panel is set on SINGLE position. In this case, burst time will be independent from
the auxiliary generator frequency.
Burst can be triggered with an external signal instead of using the auxiliary
generator, by setting rear panel selector [24] at EXT and entering trigger signal into the
input connector [23] with TTL compatible levels.
04/2003
rather accurately, may be
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