HP 8559A Operation And Service Manual page 115

MODEL 8559A
5-17. POWER SUPPLY CHECKS AND ADJUSTMENTS (Cont'd)
The two following voltage adjustments,
must be performed while the spectrum analyzer is still cold (during first five
minutes after turn-on). If the instrument has been operating longer than five
minutes, turn off the display mainframe, remove A8 and A9 assemblies, and
let them cool on bench for 15 minutes. Replace the two assemblies and
proceed with adjustment of A9R2 and A8R62 during the first five minutes
after turn-on.
7. Connect digital voltmeter to
+
ter indication of
8. Connect digital voltmeter to VO test point A8TP2. Set spectrum analyzer SWEEP TIME/DIV control to
10 ms and SWEEP TRIGGER control to SINGLE. Turn ALT IF and SIG IDENT on (pushbuttons
depressed).
9. Voltage at A8TP2 will alternate between two values each time a sweep is triggered. Trigger sweep a few
times until voltmeter indicates least negative VO voltage. Adjust VO potentiometer A8R62 for a voltmeter
indication of 2.00
-
ADJUSTMENTS
NOTE
+
0.100 Vdc.
0.10 Vdc.
+
+
ADJUSTMENTS