Service manual
Table Of Contents
- 1. Introduction
- 2. The RA-3/3A Chassis
- 3. RA-3/3A Power Supply Troubleshooting
- 4. RA-3/3A Shutdown and Self-Diagnostics
- 5. RA-3/3A Deflection Circuits
- 6. RA-3/3A Video Process Troubleshooting: T & S Models
- 7. Troubleshooting the RA-4 Chassis
- 8. RA-4/4A Power Supply Troubleshooting
- 9. RA-4/4A Protect Circuit Troubleshooting
- 10. RA-4/4A Deflection Circuit Troubleshooting
- 11. RA-4/4A High Voltage Circuit Troubleshooting
- 12. RA-4 Video Troubleshooting
- 13. Troubleshooting the RA-4A Chassis
- 14. RA-4A Video Circuit Troubleshooting
- 15. Troubleshooting the RA-5A Chassis
- 16. RA-5A Power Supply Troubleshooting
- 17. RA-5A Protect Circuit Troubleshooting
- 18. RA-5A Deflection Circuit Troubleshooting
- 19. RA-5A High Voltage Circuit Troubleshooting
- 20. RA-5A Video Path Troubleshooting
- 21. Troubleshooting the RA-6 Chassis
- 22. RA-6 Power Supply Troubleshooting
- 23. RA-6 Protect Circuit Troubleshooting
- 24. RA-6 Deflection Circuit Troubleshooting
- 25. RA-6 High Voltage Circuit Troubleshooting
- 26. RA-6 Video Circuit Troubleshooting
- 27. Troubleshooting the AKB Circuits
- 28. Auto Registration Troubleshooting
- 29. Model-to-Chassis Cross Reference
36
8. RA-4/4A Power Supply Troubleshooting
FIGURE 8-6 - REGULATION
FROM
Q6006/E
SOFT
START
11V
135V
V OUT
SENSE
IC6101
VCC CONTROLLER
SE135N
COLLECTOR R6128
IC6005
VCC OUT
PC123FY2
R6028 D6023
D6024
R6033
R6029
C6027
E
AMP
1-
E AMP2-
REF OUT
DPC
E1
E2
IC6003
OSCILLATOR
IR3M02
TO
CONVERTER
DRIVER
IC6002 &
IC6004
1
3
2
1
2
4
3
1
6
RT
15
14
13
9
10
G BOARD
8.6TVP14 6/18/02
is the most common result obtained. IC1601 and its connection to the 135V line are the next check. The most
common cause of excessive B+ is an open or increase in value of the resistor connecting the 135V to IC1601
(R6115 in this chassis).
If shorting pin 2 of IC1601 does not stop the over-voltage problem, short pin 4 of IC6005. If the voltage now
drops, replace IC6005. If it still does not drop, IC6003 or one of the input components may be open.
Low B+: Check the voltage at IC6005, pin 1 and 2. There should be at least .6VDC difference with pin 2 being the
lowest. If there is, the optical isolator is being told to increase the frequency. If there is little or no voltage
potential across pins 1 and 2, disconnect pin 4 of IC6005. Turn the unit on and it should go into over-voltage
shutdown. If B+ is still low, check components at error input of IC6003 and if OK, replace the IC.