AVTECH ELECTROSYSTEMS AVR-GHV1-B, Инструкция по эксплуатации

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The burst mode may also be used with the front-panel “Single Pulse” pushbutton as a
trigger source. (Pressing the pushbutton will actually generate a single burst, rather
than a single pulse, in this mode.) Computer commands can also trigger a burst.
To control the burst count and timing from the front-panel, use the “N” and “BUR”
menus. To control them using computer commands, use the SOURce:PULSe:COUNt
and SOURce:PULSe:SEParation commands, as described in the programming manual.
The pulse spacing is constrained by several factors:
1. The maximum PRF limitation of the instrument applies within the burst. That is,
timing between two consecutive leading edges must lie between a minimum of
1/PRF
MAX
and a maximum of 1.0 seconds, where PRF
MAX
is the maximum
pulse repetition frequency specification for the instrument.
For this instrument, the maximum PRF for the instrument is 1 kHz, so the time
between two leading edges within the burst may not be smaller than 1
millisecond. The total number of pulses per second (i.e., Trigger Frequency x
Burst Count) must also be less than 1 kHz.
2. The maximum duty cycle limitation of the instrument can not be exceeded inside
the burst. Within the burst, the duty cycle may be calculated using DC
BURST
=
100% x Pulse Width / (Pulse Width + Pulse Separation). The total average duty
cycle is equal to DC
AVG
= 100% x Pulse Width x Burst Count x Trigger
Frequency. Both DC
BURST
and DC
AVG
must be less than the rated maximum
duty cycle of the instrument.
For this instrument, the maximum duty cycle is 80%.
DELAY
(VARIABLE)
PULSE WIDTH
(VARIABLE)
SYNC OUT
MAIN OUTPUT
BURST PULSE
SEPARATION
BURST COUNT (N),
VARIABLE FROM 1 TO 500.
(N = 3, IN THIS EXAMPLE)
PROPAGATION DELAY (FIXED)
TRIG
(external input)
> 50 ns
TTL LEVELS
(0 and 3V-5V)
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