Agilent Technologies 856290216 service manual Procedure 2. Al Front Frame/Al8 CRT, Removal

Procedure 2. Al Front Frame/Al8 CRT

Procedure 2. Al Front Frame/Al8 CRT

Removal

Warning The voltage potential at A8AlW3 is +9 kV. Disconnect at the CRT with caution1 Failure to properly discharge A8AlW3 may result in severe electrical shock to personnel and damage to the instrument.

1.Remove the spectrum analyzer cover assembly as described in “Procedure 1. Spectrum Analyzer Cover.”

2.Fold out the A2, A3, A4, and A5 assemblies as described in “Procedure 5. A2, A3, A4, and A5 Assemblies Removal,” steps 2 through 6.

3.Disconnect AlAlWl from A3J602.

4.Place the spectrum analyzer top-side-up on the work bench.

5.Connect the spectrum analyzer line-power cord to provide proper grounding while discharging the A6AlW3 post-accelerator cable. Make sure that the spectrum analyzer line-power switch is in the off position.

6.Connect a high voltage probe (lOOO:l), such as the HP 34111A to a voltmeter with a 10 megohm input.

7.Connect the clip lead of the probe (ground) to the chassis of the spectrum analyzer.

8.Slip the tip of the high voltage probe under the rubber shroud of the A6AlW3 post-accelerator cable to obtain a reading on the voltmeter. See Figure 4-2.

9.Keep the high voltage probe on the post-accelerator connector until the voltage has dropped to a voltmeter reading of less than 5 mV (less than 5 V at the connector). This normally takes about 30 seconds.

10.Disconnect the line-power cord from the spectrum analyzer.

Warning To avoid possible electrical shock, in the next step, use a screwdriver having a conductive metal shank and tip, with an insulated handle.

11.Connect one end of a wire clip lead to a small screwdriver having a conductive shank and tip. Connect the other end of the clip lead to the CRT shield assembly as shown in Figure 4-2. Hold the insulated screwdriver handle and slip the tip of the screwdriver under the rubber shroud of the A6AlW3 post-accelerator cable, shorting the cable to ground through the CRT shield assembly. See Figure 4-2.

12.Using a small screwdriver with the shank in contact with the CRT shield assembly, slip the tip of the screwdriver under the A6AlW3 post-accelerator cable rubber shroud and short the cable to ground on the CRT shield assembly.

13.Pry out the black grommet protecting post-accelerator cable A6AlW3 from the CRT shield assembly.

14.Carefully unsnap the A6AlW3 post-accelerator cable from the CRT and discharge it by shorting the cable to chassis ground on the CRT shield assembly.

Assembly Replacement 4-5