Avtech AVMH-1A-C, Инструкция по эксплуатации, Страница: 16 / 29

4. DELAY Control. Controls the relative delay between the reference output pulse
provided at the SYNC output and the main output. This delay is variable over the
range of 0 to 50 ns, approximately. At high frequencies, this delay should be kept
nearly fully counter-clockwise, so that the delay does not exceed the period
(otherwise, the triggering may stop). The variable delay circuitry only functions in the
internal trigger mode. The delay is not adjustable when triggering externally.
5. TRIG Input. The external trigger signal is applied at this input when the PRF range
switch is in the “EXT” position.
For standard units, a TTL logic level pulse (i.e., 0V = TTL LOW, +3V to +5V = TTL
HIGH) is required to trigger this input, and the input impedance is 50Ω to ground (or
1kΩ, for units with the -Z1K option).
The input pulse width should be > 10 ns.
6. SYNC Output. This output precedes the main output, and is typically used to trigger an
oscilloscope. When triggering internally, the SYNC pulse width varies, but is always >
10 ns. When triggering externally, the SYNC output is a buffered replica of the TRIG
input. The amplitude is fixed at +3V approximately, and this output will drive 50 Ohms
or higher.
7. Pulse Width Controls. These two dials control the pulse width. The T
R
dial
determines the position of the impulse rising edge, and the T
F
dial determines the
position of the impulse falling edge. Used together, they control the pulse width.
8. Amplitude Control. This dial controls the pulse amplitude.
9. OUT Connector. This is the main output. (This output requires a 50Ω load to function
properly).
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