Discharge Procedure for High Voltage and

CRT

Warning

Warning

2.High-Voltage Adjustment (SN 3004A and Above)

16.With the front-panel INTENSITY control fully counter clockwise, wait approximately 10 minutes to allow the high-voltage supply to stabilize and the CRT to normalize. This sofl turn-on will extend CRT life expectancy, particularly if a new CRT has just been installed.

17.Readjust AlA6R103 HV ADJ for a DVM indication equal to the voltage determined in step 15.

18.If a new CRT has just been installed do the following:

a.Set the front-panel INTENSITY control so the CRT trace is barely visible.

b.Wait an additional 30 minutes for the CRT to normalize.

c.Readjust AlA6R103 HV ADJ for a DVM indication equal to the voltage determined in step 15.

19.Set the LINE switch to STANDBY. Remove the ac line cord from each instrument section.

20.Wait at least one minute for the MAINS power-on indicator AlASDSl (red LED) to go out completely before proceeding.

21.Disconnect the high-voltage probe from AlA3TP2A.

22.Replace the cover on the AlA High-Voltage Regulator Assembly.

23.The High-Voltage adjustments are now completed. If the AlA assembly has been repaired or replaced, perform adjustment procedure 3, “Preliminary Display Adjustment (SN 3004A and Above)“, and then adjustment procedure 4, “Final Display Adjustments (SN 3004A and Above)“. If the AlA assembly functions properly and does not require compensation, proceed directly to adjustment procedure 4, “Final Display Adjustments (SN 3004A and Above)“.

The High-Voltage Adjustment procedure does not require the removal or discharge of the Al A3 High-Voltage Regulator or AlVl CRT assemblies. However, if for any reason the AlA High Voltage Regulator Assembly, the CRT, or the CRT post-accelerator cable must be removed, perform the following procedure to ensure proper safety.

This procedure should be performed by qualified personnel only. Voltages are present which, if contacted, could cause serious personal injury. Approximately -2400 V dc can be present on the AlA High-Voltage Regulator assembly even when the ac line cord is disconnected. The CRT can hold a + 9500 V dc charge

for several days if the post-accelerator cable is improperly disconnected.

1. Remove the ac line cord from both instrument sections.

With the ac power cords disconnected, voltages can still be present which, if contacted, could cause serious personal injury.

2.Obtain an electrician’s screwdriver which has a thin blade at least eight inches long. The handle of the screwdriver must be made of an insulating material.

Adjustments 3-43