12

Display/Power Supply Section

The Display/Power Supply Section contains the A6 Power Supply, A6Al HV Module, Al7 CRT Driver, and Al8 CRT. Figure 12-1 illustrates the section block diagram. Table 12-1 lists signal versus pin numbers for Power Cable Wl.

 

 

 

 

P a g e

Troubleshooting

Using the TAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . 12-4

Blank

Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-5

Blank Display

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-6

Display

Distortion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-7

Focus Problems

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-8

Intensity

Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . 12-9

A6 Power

Supply Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . 12-11

Dead Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. 12-11

Line Fuse Blowing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-13

Supply Restarting Every 1.5 Seconds (Kick Start) . . . . . . . . . . . . . . . . . . .

. . . 12-13

Low Voltage

Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. 12-13

High

Voltage

Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. 12-14

CRT

Supply

Dropping Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . 12-15

Blanking Signal.....................................................

12-15

Buck

Regulator Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . 12-16

DC-DC Converter Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . 12-16

Power

Up . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.. 12-17

Warning The A8 Power Supply and A6Al High Voltage Assemblies contain lethal voltages with lethal currents in all areas. Use extreme care when servicing these assemblies. Always disconnect the power cord from the instrument before servicing these assemblies. Failure to follow this precaution can represent a shock hazard which may result in personal injury.

Warning The voltage potential at A6AlW3 is +9 kV. If the cable must be disconnected, always disconnect it at the CRT with caution! Failure to properly discharge A6AlW3 may result in severe electrical shock to personnel and damage to the instrument. See Chapter 3, Procedure 2.

Warning Always use an isolation transformer when troubleshooting either the A6 Power Supply or the A6Al HV Module. When using an isolation transformer, connect a jumper between AGTPlOl and A6TP301. This connects the circuit common to earth ground. Remove this jumper when the isolation transformer is not used.

Display/Power Supply Section 12-l