HP 8642A - Page 114

Model 8642A/B
Operation
Amplitude Sweep (cont'd)
2) Calculate the sweep step size automatically selected.
The result can be a non-integer, but actual amplitude points are truncated to 0.1 dB
(the total number of points is equal to the total number of steps + 1).
The sweep step size is the maximum of:
0.1 dB
or
| Start Amplitude (in dBm) - Stop Amplitude (in dBm) \
INTEGER OF (
Sweep Time {in mS)
) - 1
\ 3 ms I
3) Calculate a sweep time that could be selected for a desired number of steps.
3a) First you must ensure that the desired number of steps is between the maximum
and minimum number of steps possible.
The maximum number of amplitude steps is equal to:
| Start Amplitude (in dBm) - Stop Amplitude (in dBm) \
0.1 dB
The minimum number of amplitude steps equals the minimum of:
5
or
| Start Amplitude (in dBm) — Stop Amplitude (in dBm) \
0.1 dB
3b) If the desired number of steps is equal to the maximum, use a sweep time setting
(in ms) equal to or greater than the result of the following equation:
(Number of Steps + 1) X 3 ms
If the desired number of steps is less than the maximum calculated in 3a, use a sweep
time setting (in ms) greater than or equal to the result of the above calculation but less
than the result of the following calculation:
(Number of Steps + 2) X 3 ms
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