My roomate has a 60UX54B Ultravision. It wouldn't stay on so we started smacking it to get it to play, that worked for a while acting like a loose connection. We opened the back up and tapped around on the the main board looking for the loose connection. We could get it to come and stay on with pressure on the board, it was acting like a cold solder. I took a soldering iron and worked through solder points around the area that seemed to react to probing with no result. I suspect a bad component on the board but can't pin it down with my primitive methods.
What should I look for that would cause this flicking on & off? Replace the board? Does anyonedo board level repairs on these things?
RT
Oh cheez, a cold solder connection in a set can be a service mans nightmare. he may think he found the problem, will have the set on a test after the repair for days, You go to deliver the set, and low and behold, the problem comes back again. This can turn out to be a bad componet, sure! I have found that in thes cases, its best to get a service manual, and follow a flow chart or a block circuit diagram to see whats missing when the sets in a faulty state. its ok to tap around on the boards witha insulated insterment, but in some cases it will damage a circuit board and cause permanet damage, as I was once working on a dog of a repair on an projection set, had what apperared to be a bad solder connection. After probing and soldering, all of a sudden a capacitor Blew up right in!front of me! It turns out that there was an internal connection iside the capacitor that was causing the intermittant problem. i repaired the damaged board, replaced the capacitor, and that was the end of that one. Hope this helps.. Opps almost forgot There is a service manual avail for a download at a cheap price of around $18.00 bucks. aHere If you do not understand how to read a schematic or to trace out a voltage source, please play iot safe and seek the aid of a trained service tech on this repair. Good Luck and please inform us how you made out or what you did to fix this set.
Larry, Thanks for the response. I was hoping for an easy fix looking for a cold solder. The bad capacitor sounds more like what I found. The set would shut down eventually tripping a breaker, I suspect in the power supply. I can barely follow a schematic and will attempt that with a simple meter and see if I can trace the bad component. wish me luck!
Is the sound and picture going on and off or just the picture?
Try resoldering the high voltage transformer, and bad looking connections it. Make sure all of the plug connections are in tight.