Agilent Technologies 8360 L Series, Руководство по обслуживанию

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10. Modulator Offset and Gain
Description and Procedure
In this pro cedure, the ALC mo dulation oset and gain calibration constan ts are adjusted
to linearize the ALC mo dulator resp onse to the ALC p o w er lev el reference v oltage. Default
v alues are en tered for the mo dulator oset calibration constan ts and in ternal rm w are is
activ ated to set the mo dulator gain calibration constan ts. The syn thesizer is then set for a
p o w er sw eep across the en tire lev eled ALC range ( 020 to the maximum lev eled p o w er). The
in tegrator lev el signal on the ALC b oard is monitored to v erify linearity .
If necessary , the mo dulator oset v alues are mo died.
1. F or 8360 B-Series only , connect the equipmen t as sho wn in Figure 3-23. Preset the
instrumen ts and let them w arm up for at least one hour. F or 8360 L-Series, start this test
at step 2.
Figure 3-23. Modulator Offset and Gain Adjustment Setup
Equipment
Digitizing Oscilloscop e HP/Agilent 54111D
Oscilloscop e Prob es HP/Agilent 10431A
2. On the syn thesizer, set:
4 SERVICE 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Adjust Menu
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Calib Menu
3. If y ou ha v e replaced the low band assem bly (A24) or the dual mo dulator assem bly
(A38), set the ALC oset calibration constan ts to the default v alues given in T able 3-6 .
Otherwise, skip to step 7 for 8360 B-Series or skip to the next adjustmen t for 8360
L-Series.
Select
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Select Cal . Using the n umeric k eypad, en ter the n um b er of the rst calibration
constan t in T able 3-6 . T erminate y our en try with the 4
ENTER
5 k ey .
3-62 Adjustments
Modulator Offset and Gain
Agilent 8360