Tektronix TDS3000 640 TDS3000 Series Service Manual, Figure 628: Front panel/display backlight power troubleshooting

Maintenance
6–40 TDS3000 Series Service Manual
Power off oscilloscope.
Disconnect AC power cord.
Reconnect J700 cable to main board.
Disconnect J950 cable from main board.
Connect AC power cord.
Power on oscilloscope.
Measure voltages on connected J900
cable as shown in Figure 6–27 (page 6–39).
Measure voltages on
connected J900 cable as shown
in Figure 6–27 (page 6–39).
Power off oscilloscope.
Disconnect AC power cord.
Disconnect J700 cable from
the main board.
Connect AC power cord.
Power on oscilloscope.
Replace the Front
Panel module.
No
Yes
Are voltages within
tolerance?
Power distribution problem on main
board or display module. Proceed to
Figure 6–29.
No
Yes
Are voltages within
tolerance?
Replace high voltage
inverter board.
Continued from Figure 6–27.
Figure 6–28: Front panel/display backlight power troubleshooting