2. High-Voltage Adjustment (SN 3001A and Below)
be performed with the DVM manually set to the 100 V range
on the HP 3456A display).
H I G H
V O L T A G E
R E G U L A T O R
,
.
Figure 3-6. Location of High Voltage Adjustments
4. Set the spectrum analyzer LINE switch to ON. Set the front-panel
INTENSITY control fully counterclockwise (CRT beam at
to prevent possible damage to the CRT.
5. Note
DVM indication at
DVM Indication:
6. Connect the high-voltage probe to the DVM. Connect the probe to
7. Note the DVM indication.
DVM Indication:
8. Divide the DVM indication in step 7 by the DVM indication in
step 5. This gives the calibration factor needed to compensate for
high-voltage probe error.
Calibration Factor:
9. Disconnect the high-voltage probe from
Set the
spectrum analyzer LINE switch to STANDBY. Remove the ac line
cord from both instrument sections.
The MAINS power-on indicator
(red LED) should
be completely off before proceeding with this procedure. See
Figure 3-6. The indicator will remain lit for several seconds after
the ac line cord has been removed, and will go out slowly (the
light becomes dimmer until it is completely out).
With the protective cover removed in the following step, do not
place hands near the
High-Voltage assembly. High voltage
(approximately -4000 V dc) can be present even when the ac line
cord is disconnected.
Adjustments 3-33