AVTECH ELECTROSYSTEMS AVR-GHV1-B, Instructions Manual

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OUTPUT IMPEDANCE
The AVR-GHV1-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 40 ns. However, since the output
impedance is 50Ω, the rise and fall times will degrade if cable lengths longer than 1
meter (3 feet) are used on the output, due to the cable capacitance. The maximum
usable cable length is 2 meters (6 feet).
LOAD IMPEDANCE
The AVR-GHV1-B can drive load impedances of 100 kΩ or higher. It is NOT designed
to drive 50 Ω loads or highly capacitive loads. (The AVR-GHV1-B is tested with
capacitive loads of 330 pF. Load capacitance should not exceed 330 pF.)
BURST GENERATION (-BR OPTION)
The waveforms given above assume that a single output pulse is generated for each
trigger event (regardless of the source). However, when the burst mode feature is used
on units with the -BR option, the instrument can generate 1-500 pulses for each
individual trigger event. The number of output pulses in each burst can be adjusted
from 1 to 500 using the front-panel controls (using the “N” menu), or by a computer
command. The time between pulses (i.e., from the falling edge of one pulse to the rising
edge of the next pulse) can also varied from 1 ms to 1.0 seconds from the front panel
(using the “BUR” menu), or by computer command.
The figure below shows burst mode operation (i.e., N > 1) used with internal triggering:
The figure below shows burst mode operation used with external triggering:
DELAY
(VARIABLE)
PULSE WIDTH
(VARIABLE)
SYNC OUT
(generated by the
internal oscillator)
MAIN OUTPUT
BURST PULSE
SEPARATION
BURST COUNT (N),
VARIABLE FROM 1 TO 500.
(N = 3, IN THIS EXAMPLE)
PERIOD = 1 / FREQUENCY
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