HP 70000 series, Руководство пользователя

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PRESEL PEAK
(preselector peak) adjusts the tracking of the preselector lter to yield maximum amplitude
accuracy at the active marker position. If a marker is not present,
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PRESEL PEAK places a
marker at the highest signal level.
Each time the preselector is peaked, a value is stored in the preselector digital-to-analog
converter (D A C). Up to four values can be stored, one for each of four frequency ranges:
T able 4-13. Preselector D A C Frequency Bands
Band Frequency Range
1 2.7 GHz to 6.2 GHz
2 6.0 GHz to 12.7 GHz
3 12.5 GHz to 19.9 GHz
4 19.7 GHz to 22.0 GHz
Whenever a measurement is made , the current preselector-D A C value corresponding to the
selected measurement range determines the preselector tracking. Press
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PRESEL PEAK to
repeak the preselector and store a new When measuring frequency spans greater than 0 Hz,
the analyzer must be swept at least once to peak the preselector . Thus , the analyzer requires
several minutes to peak the preselector when measuring with slow sweep times . T o execute the
peaking function quickly , change the span to 0 Hz before pressing
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PRESEL PEAK .
Functional Type:
preselector
Firmkey A ccess:
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Freq
Preset State:
O
4-118 Softkey Descriptions