AVTECH ELECTROSYSTEMS AVG-4A-B, Instructions Manual

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GENERAL INFORMATION
BASIC PULSE CONTROL
This instrument can be triggered by its own internal clock or by an external TTL trigger
signal. In either case, two output channels respond to the trigger: OUT and SYNC. The
OUT channel is the signal that is applied to the load. Its amplitude and pulse width are
variable. The SYNC pulse is a fixed-width TTL-level reference pulse used to trigger
oscilloscopes or other measurement systems. When the delay is set to a positive value
the SYNC pulse precedes the OUT pulse. When the delay is set to a negative value the
SYNC pulse follows the OUT pulse.
These pulses are illustrated below, assuming internal triggering and a positive delay:
Figure A
If the delay is negative, the order of the SYNC and OUT pulses is reversed:
Figure B
The next figure illustrates the relationship between the signal when an external TTL-
level trigger is used:
SYNC OUT
(generated by the
internal oscillator)
100 ns, FIXED
MAIN OUTPUT
PULSE
WIDTH
(FIXED)
DELAY > 0
(VARIABLE)
AMPLITUDE,
VARIABLE
3V, FIXED
SYNC OUT
(generated by the
internal oscillator)
100 ns, FIXED
MAIN OUTPUT
DELAY < 0
AMPLITUDE,
VARIABLE
3V, FIXED
PULSE
WIDTH
(FIXED)
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