[TV] Mitsubishis CS2710R UMC-2 Chassis High voltage shutdown Problem

[dagaz@xxxxxxx]

Have a Mitsubishi CS-2710R  UMC-2 Chassis built 1992.
 Steps of what has occurred:

 1. TV died, no picture or sound.
 2. Found F951 blown going to 130V regulator.
 3. Put new fuse in, blew immediately.
 4. Found Horizontal Output Transistor bad - shorted 
 5. Replaced with new exact part number replacement.
 6. Upon power up high voltage came on for about 2 seconds then stopped.
 7. Upon susbequent power ups can see hear high voltage for about 0.5 seconds only.
 8. Lifted R520 to disable High voltage shutdown circuit.
 9. TV powered up subsequently, picture looks good and sound OK.
 10. TV shut down after 35 minutes, Horizontal transistor shorted again. Fuse blew.
 11. Replaced high voltage caps around HOT. C552,C570 and put in new HOT.
 12. TV still needs High voltage shutdown defeaed to work.
  13. Powerd back for 2 minutes and then turned it off.
  14. Made the 4 ohm R555 to 12 ohms in idea it woudl drive T551 High votage transformer less.
  15. Still sees high voltage shutdown condition.

   ? What regulates or maintains the high voltage output level to CRT?
   My next step is to replace all teh high voltage caps on the pioncushiuon board with new to
   help out the HOT circuit, but do not knwo if thsi will help the overvoltge condition.
dagaz
 dagaz@xxxxxxx
  
  ?
  
 

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