HP 85108, Системное руководство

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Figure 3-16. S
21
, Pulse Profile, Thru
1. Set Pulse P olarit y . After instrumen t preset, the pulse p olarity is set to High for the On
p erio d of the pulse app earing at the HP 8510 rear panel PULSE OUTPUT connector. Use
the following pro cedure to set the pulse p olarity .
Press 4 SYSTEM 5
NNNNNNNNNNNNNN
MORE
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PULSE CONFIG
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PULSE OUT: HIGH .
F or in ternal pulse mo dulation and in ternal triggering, time equals zero seconds is alwa ys
the p oint where the pulse transitions to the active lev el. The in ternal pulse mo dulator in
the RF source turns the RF pulse On when the analyzer output is p ositiv e, so the noisy
part of the trace will c hange lo cation dep ending on the pulse p olarit y .
2. Set Pulse Width. After instrumen t preset, the pulse width is set to 10 microseconds. Press
the following k eys to set a dieren t pulse width.
Press 4
SYSTEM
5
NNNNNNNNNNNNNN
MORE
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PULSE CONFIG
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PULSE WIDTH .
Use the knob, step k eys, or n umeric en try to set the desired pulse width.
3. Set Dut y Cycle Limit. After instrumen t preset, the dut y cycle limit is set to 10. This
means that the maximum dut y cycle will nev er b e allo w ed to b e greater than 10 p ercen t
regardless of the pulse width.
T o set the dut y cycle limit, press
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
DUTY CYCLE on the Pulse Conguration men u. Use the
knob, step k eys, or n umeric en try to set the desired maximum dut y cycle limit. Note that
the actual dut y cycle may b e less.
4. Set Measuremen t Time Span. The HP 8510 automatically c ho oses the minimum p ossible
(given the HP 8510 hardw are and rm w are capabilities) time b et w een samples, and th us
the measuremen t resolution p erio d, dep ending up on the larger of the pulse width time
or the stop time. This results in a minimum p ossible span time whic h dep ends up on the
curren t n um b er of p oints.
3-20 Operation