HP 3585A Service Manual page 172

Adjustments
e. Push the cable completely onto A I J3 . check that a display similar to Figure 5-38 is ob­
tained.
I f the instrument passes the Calibrator Accuracy test in the Per for­
mance Test section, go on to paragraph 5-36. Only if the
Calibrator Accuracy Test has failed and you are certain your
source is not at fault should you per form the following steps.
f. Using the results of the Calibrator Accuracy Test, determine if the 40MHz point is
higher or lower than the lOMHz point.
g. Select a new Al C50· from the list below. Choose a s:maller value to raise the 40MHz
point and a larger value to lower the 40MHz point. (This capacitor affects the Calibrator's
frequency response above 20MHz.)
h. Remove the Input/Conversion box from the 3585.
i. Remove the cover on the Input board side.
j . Replace Al C50· .
k. Replace the cover and all screws.
1 .
Replace the Input/Conversion box in the instrument.
m. Retest the Calibrator Flatness with the Calibrator Accuracy Test.
5-58
REF -25. 0 dBm
10 dB/O I V RANGE -25. 0 dBm
- - - - - - - - - -- - - - -
CENTER 20 000 000. 0 Hz
RBW 30 KHz VBW 30 KHz
Figure 5·37. Calibrator Symmetry Adjus1tment (A 1 R52)
NOTE
Capacitor Value
IOpf
1 2pf
1 6pf
MARKER 2 0 000 000. 0 Hz
-77. 2 dBm
-
- - - - - - - -
SPAN 40 OClO 000. 0 Hz
ST . 2 SEC
-hp- Part Number
0160-2257
0160-2259
01 60-2262
Model 3585A