Giga-tronics 8650B Series, Руководство по эксплуатации

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Series 8650B Universal Power Meters
2-32 Publication 31470-001, Rev C, November 2, 2017
Peak power measurements are made by sampling the RF input at a point which is defined by a trigger level, a
delay, and a delay offset (See Figure 2-17). The initial triggering event occurs when the power input (or in the
case of external triggering, a voltage input) reaches a threshold, which has been defined as the trigger level by
the user. The sample is then taken after a delay, which have been defined by the user. To this delay can be
added a positive or negative delay offset.
The delay offset is not necessary for peak measurement, but in some applications it is a convenience. For
example, a small offset (even a negative offset) might compensate for the difference between the trigger point
and some other point of interest (such as the half-power point) especially in applications where pulse width is
being measured. Or if it is necessary to measure the levels of various pulses within a pulse train, the pulses can
be sampled successively by changing the delay offset. A fixed delay insures that each pulse is sampled at the
same point in its cycle.
Figure 2-17: Delay & Delay Offsets