User Manual

4.4.3. Sweeping mode:
* Press【Menu】-key and then set sweeping mode. Set the value as 0, the character “linear” will be
lighted, and the sweeping mode now is linearity. Set the value as 1, the character “log” will be lighted, to
select logarithm mode.
* Under linearity sweeping mode, the frequency step is fixed, but a fixed frequency step always does a bad
effect when sweeping comparatively wide-range frequency.
* In that case, the resolution is high when sweeping high end of frequency, the frequency changes slowly,
and the sweeping is fine.
* But the resolution is low when sweeping the low end of frequency, the frequency changes very quickly,
the sweeping is rough. *
* So linearity sweeping is applicable only for sweeping with narrow frequency range.
* Under logarithm sweeping mode, the frequency step value is not fixed but changes according to logarithm
relation.
* When sweeping the high end of frequency, the frequency step value is comparatively large; when
sweeping the low end of frequency, the frequency step value is comparatively small.
* The frequency change is comparatively average for sweeping with wide frequency range.
* So logarithm sweeping is applicable for sweeping with wide frequency range.
4.4.4. Sync output:
* During frequency sweeping, the “Sync” port on the front panel output a sync signal.
* A sync signal is a pulse wave signal with TTL level, of which the rising edge of the pulse is match along
with the start point of the sweeping, and the falling edge is match along with the middle point of the
sweeping area, the period of the pulse wave is the same with sweeping time.
4.4.5 Trigger sweeping:
When continuous sweep, the generator uses internal continuous trigger source, and the sweep runs
continuously and repeatedly. Press【trig】key to light “trig” keyboard indicator, and the sweep will end when
reaching to the end point, then each time you press【trig】key, the sweep runs once and then stops at the
start frequency waiting for the next trigger. External trigger is also available, input TTL trigger signal into the
《Trig In》port on the rear panel. The sweep runs once at the rising edge of each trigger signal. Of course,
the period of trigger signal should be larger than the sweep time set. In trigger sweep, press【Sweep】key,
the “trig” keyboard indicator will be off and the generator resumes to continuous sweep mode.
4.5. Burst function
It is explained that in burst mode, the word “burst” means the cycle of any waveform, not only the pulse. In
burst output, instrument outputs a waveform with a specified number of cycles and at a specified period at a
starting phase, or it outputs a waveform with a specified number of cycles only single once. All the 16
waveforms could be used as burst waveform, Of course, using DC or noise signal as burst signal is invalid.
Before entering burst function, users should set the waveform, frequency and amplitude of the burst under
the continuity function.
Press 【Burst】key to light “Burst” keyboard indicator, the generator will enter into burst function.
4.5.1. Period:
Press【Menu】key to light “Period” character, and then set repeated period. Period represents time from the
start of one pulse string to the start of the next one which must be long enough to contain the pulse numbers
of setting, as the following formula shows:
Repeated period＞Pulse count ÷ Pulse frequency
If the repeated period setting is too short, the instrument will modify it to the allowable minimum value.
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