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Hitachi CT4532 Projection TV need help troubleshooting

I have an old Hitachi CT4532 and have repaired it twice allready.

Previous repairs in chronological order

  1. horizontal output transistor was replaced along with a fuse. I have only had to replace this once but it had blown before with the previous owner.

  1. Resoldered transistored on Stand Up Brd On Power/Def Board because of cold solder joints/broken loose.

Now what is currently wrong with it. Last 2 times before this I turned it on I heard a pop sound like something was arching or similar. The set worked fine each time afterwards. This time a more significant pop was heard and now the video output is fussy with many(10-12) white horizontal lines at a slight angle up from left to right. It is very dim and greyish but still has some colour in it albiet very poor. The lines can be seen when there is no video input and on any video input. Only difference is when there is video input the lines will not move. When there is no video input the lines will move accross the screen like they have not vertical hold Im not sure where to start looking for the culprit here. I cannot afford to get it fixed but have plenty of time to learn.

Reply to
Charon
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A little more information, the retrace lines showed up after the electrical discharge. This discharge was still happening. So after turning the lights off and watching it was comming from the cord on the side of the red crt. It was loose and not seated properly. I removed it and reseated it into the crt and it has since stoped arcing when turned on. It was grounding out on the frame of the TV and has cooked something. But I am unsure how to test the power supply B+ or the blanking circiut, or where they are.

Reply to
Charon

HV splitter is a common failure on that set and has not been available for years. Probably the source of the hv arcing sound you were hearing.

Reply to
dkuhajda

I dont know if you saw my second post.

But since I have found the source of the arching hv by turning off the lights. The arc was on the red crt of the projection tv. It was arching under the rubber cup of the electrode to the chassis of the TV. I removed the electrode(carefully) as it did not appear to be seated properly and reseated it into the crt. The TV had been moved before this had started happening. Since reseating the electrode there has been no further noticable arching when turning the tv on.

Now I just have to figure out why these retrace lines are showing up. Thanks for your post

- Eric

Reply to
Charon

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