Avtech AVR-G1-B, Instructions Manual

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
External Trigger: the instrument is triggered by an external TTL-level clock on the
back-panel TRIG connector.

Manual Trigger: the instrument is triggered by the front-panel “SINGLE PULSE”
pushbutton.

Hold Trigger: the instrument is set to not trigger at all.
These modes can be selected using the front panel trigger menu, or by using the
appropriate programming commands. (See the “Programming Manual for -B
Instruments” for more details.)
PULSE WIDTH MODES
This instrument has two pulse width modes:

Normal: the instrument controls the output pulse width.

PW
IN
=PW
OUT
: the output pulse width equals the pulse width of the trigger signal on
the “TRIG” connector. The instrument must be in the external trigger mode.
These modes can be selected using the front panel pulse width menu, or by using the
appropriate programming commands. (See the “Programming Manual for -B
Instruments” for more details.)
GATING MODES
Triggering can be suppressed by a TTL-level signal on the rear-panel GATE connector.
The instrument can be set to stop triggering when this input high or low, using the front-
panel gate menu or the appropriate programming commands. This input can also be
set to act synchronously or asynchronously. When set to asynchronous mode, the
GATE will disable the output immediately. Output pulses may be truncated. When set to
synchronous mode, the output will complete the full pulse width if the output is high,
and then stop triggering. No pulses are truncated in this mode.
OUTPUT IMPEDANCE
The AVR-G1-B has an output impedance (i.e., an internal resistance in series with the
output) of 50 Ohms, to provide transmission line back-matching and short-circuit
protection.
The rise and fall times are fixed at less than 20 ns. However, since the output
impedance is 50Ω, the rise and fall times will degrade if cable lengths longer than 1
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