HP 8560A, Руководство по обслуживанию

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Procedure 14. W3 Line Switch Cable
Removal
Warning
Due to possible contact with high voltages, disconnect the analyzer’s
line-power cord before performing this procedure.
1. Remove the analyzer’s cover assembly as described in Procedure 1, “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 3 through 5.
3. Disconnect from
4. Place the analyzer top-side-up on the work bench with A2 through A5 folded out to the
right.
Warning
The voltage potential at is Disconnect at the CRT with caution!
Failure to properly discharge may result in
severe electrical
to
personnel and damage to the instrument.
5. Connect the analyzer’s line-power cord to provide proper grounding while discharging the
post-accelerator cable. Make sure that the analyzer’s line-power switch is in the
off position.
6. Connect a high-voltage probe
such as the HP 34111A to a voltmeter with a
10 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 post-accelarator cable’s rubber
shround to obtain a reading on the voltmeter. See Figure 3-2.
9. Keep the high-voltage probe on the post-accelerator connector until the voltage has
dropped to a voltmeter reading of less than 5
(1ess than 5 V at the connector). This
normally takes about 30 seconds.
10. Disconnect the line-power cord from the spectrum analyzer.
11. Using a small screwdriver with the shank in contact with the CRT shield assembly, slip
the tip of the screwdriver under the post-accelerator cable’s rubber shroud and
short the cable to ground on the CRT shield assembly. See Figure 3-2.
12. Remove the three screws securing the power supply shield to the power supply, and
remove the shield.
13. Pull the cable tie Figure 3-24, to free and the post-accelerator cables.
14. Disconnect W3 from
15. Pull W3 up from between the power supply and the CRT assembly.
16. Undress W3.
17. Place the analyzer on its right side frame.
3-44 Assembly Replacement