HP 8566B Adjustment Manual page 179

2. High-Voltage Adjustment (SN 3001A and Below)
41. The High-Voltage Adjustment is completed. If an AlA2, AlA4,
or AlA assembly has been repaired or replaced, perform
adjustment procedure 3, "Preliminary Display Adjustment (SN
3001A and Below)", and then adjustment procedure 4, "Final
Display Adjustments (SN 3001A and Below)". If the AlA2,
compensation, proceed directly to adjustment procedure 4, "Final
Display Adjustments (SN 3001A and Below)".
The adjustment procedures in this manual do not require the removal
or discharge of the AlA High-Voltage Regulator or CRT assemblies.
However, if for any reason the AlA High Voltage Regulator Assembly
or the post-accelerator cable must be removed, the following
procedure ensures the proper safety.
This procedure should be performed by qualified personel only.
Voltages are present which, if contacted, could cause serious
personal injury. Approximately -4000 V dc is present on the
cord is disconnected. The CRT can hold a + 18 kV dc charge
for several days if the post-accelerator cable is improperly
disconnected.
Do not handle the AlA High-Voltage Regulator Assembly or
discharge procedure has been performed.
1. Set the spectrum analyzer's LINE switch to STANDBY, remove the
ac line cords, and remove the AlA High Voltage Regulator safety
cover.
With the ac power cord disconnected, voltages are still present
which, if contacted, could cause serious personal injury.
In the following step, a large arc of high voltage should be drawn.
Be careful.
2. Locate the snap connector on the CRT post-accelerator cable.
It is shown in Figure 3-11 as item 1. Using a long flat-bladed
with
screwdriver an insulated handle, carefully pry the connector
loose but do not disconnect the cable.
a. Using one hand, remove the end of the cable labeled item 2
in Figure 3-l 1. As the end of the cable becomes free, touch
the end of the cable to the CRT's metal cover. A large arc of
high voltage should ground to the CRT cover. The CRT is not
discharged yet!
b. Reconnect the CRT post-accelerator cable, and repeat the above
step until high-voltage arcs no longer appear.
3. Leave the CRT post-accelerator cable disconnected, and remove
the cover on the AlA High Voltage Regulator.
Adjustments 3-39