Avtech AVP-AV-1S-C, Instructions Manual

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FRONT PANEL CONTROLS
1) POWER Switch . This is the main power switch. When turning the instrument on,
there may be a delay of several seconds before the instrument appears to respond.
2) OVERLOAD Indicator . When the instrument is powered, this indicator is normally
green, indicating normal operation. If this indicator is yellow, an internal automatic
overload protection circuit has been tripped. If the unit is overloaded (by operating
at an exceedingly high duty cycle or by operating into a very low impedance), the
protective circuit will disable the output of the instrument and turn the indicator light
yellow. The light will stay yellow (i.e. output disabled) for about 5 seconds after
which the instrument will attempt to re-enable the output (i.e. light green) for about
1 second. If the overload condition persists, the output will be disabled again (i.e.
light yellow) for another 5 seconds. If the overload condition has been removed, the
instrument will resume normal operation.
This overload indicator may flash yellow briefly at start-up. This is not a cause for
concern.
3) PRF Range Switch . This switch sets the pulse repetition frequency (PRF) range of
the internal oscillator. The marked value of each position is the upper limit of the
10:1 range, approximately. The vernier dial directly below the switch varies the PRF
within the set range.
If this switched is set to the “EXT” position, the instrument is triggered by a signal
applied to the TRIG connector, rather than by the internal oscillator.
4) TRIG Connector . When the PRF Range Switch is set to “EXT”, the instrument is
triggered by a TTL pulse applied to this connector. The pulse must be at least 50 ns
wide.
When the PRF Range Switch is set to one of the four internal oscillator ranges, this
connector is an output, which supplies a 2V, 200 ns wide pulse for each trigger
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