HP 70000 series, User Manual

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TRIGGER DELAY
Control the trigger delay or pre-trigger for the currently selected ADC.
It is sometimes desired to have a delay between the occurance of a trigger (particularly an
external trigger) and the taking of a sweep . This is particularly true when the desired sweep
time is much less than the desired delay . Without trigger delay , trace resolution must be
sacriced to allow both the trigger and the desired data to be captured.
With TRIGDEL, one can select a delay between the trigger and the taking of a sweep . F or the
HP 70900B local oscillator source internal ADC, this delay is in addition to the normal internal
trigger latency . F or the HP 70700A digitizer ADC, this is a true trigger delay . The delay works
for any trigger type .
If the trigger delay is not zero , an annunciator \T" (T au) appears on the screen to indicate this .
The annunciator is just to the right of the \ROFFSET" annunciator location.
F or the HP 70900B local oscillator source , TRIGDEL species additional delay . Depending
upon the measurement setup , the internal latency may be signicant (but steady for that
measurement setup).
F or the HP 70700A digitizer , the error \ADC trig delay range" will be given if the specied
trigger delay value is outside of the supported range . This error may occur even if TRIGDEL is
not what was changed.
A range as specied for each ADC. F or the HP 70900B local oscillator source internal ADC, the
range is from 0 to 52428 uS with a resolution of 1 uS.
F or the HP 70700A digitizer , the range is from -CT*N to CT*(1048574-N) with a precision of CT
(CT = time per bucket, N = number of buckets in the rst band). If the normal (Rosenfell)
detector is selected, the maximum delay is half of the above maximum (the minimum is the
same).
Functional Type:
bandwidth
Firmkey A ccess:
NNNNNNNNNNNNNNNNN
BWSwp
Preset State:
0
4-170 Softkey Descriptions