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Joe, Electronic Tech
Category: TV
Satisfied Customers: 831
Experience:  Over 30 years in electronics, Board Repair, TV's, Gaming,
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Magnavox TV repair... got a 42 flat screen (LCD ) thats about

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Magnavox TV repair... got a 42" flat screen (LCD?) that's about 3 years old...just stopped playing (no power)...replaced fuse and new fuse blew immediately when I plugged the cord in... took set to a local TV repair joint and they advised that it would be 330 some odd bucks to replace a "power supply board"... I believe I can fix this thing with some expert guidance and a print.

It sounds like that you got a power surge and what you need is a meter with a diode check, and you need to start checking are the semiconductors for a dead shot. If you get a reading on any conductivity on any leg Reading .3-.7 on any leg, that component is probaby OK, Some Diodes will re shorted in the circuit and you would have to remove them and checked them again.

Or you can take the power supply and ask them to replace the bad components and recap it for you and you will give them about 150-200. I just did one for a friend of mine for 55 dollars. He bought the supply to me and I refurbished it.

Customer: replied 7 years ago.

I'm following you, Joe. Do you think a novice like me could use a print on the thing? Or should I just take the bad caps/ semi conductors to my local Radio Shack to help me identify the values/ types? Thanks in the mean time! Guy

We recap dead power supples all the time here in las vegas and it brings most of them back a live without replacing semiconductors. That would be a go place cheap place to start. Make sure to put electronlyic caps in right porlaity or they will blow up.

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Customer: replied 7 years ago.
Anyone, I'm half way there. I ordered up and replaced all the elyrolytic caps (and a mosfet and diode that was de-soldered at TV repair joint) and now I have sound but no picture. Does the power supply board also power the screen (LCD)?... any suggestions on what I should try next? Thanks ! Guy
The inverter, sometimes there are two, and sometimes just one, they put out the High voltage to the panel, to light it up. And sometime they can be repair by replacing a couple of caps. And you will see a in line fuse on the board,that might be open, or it could be very small surface mounted fuse. The location will Be label "F", on the board. The inverters is what lights the back light. Good luck.
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Customer: replied 7 years ago.
Is the inverter on a different board than the power suppy board?
Customer: replied 7 years ago.
Well, it's amazing what can happen when all the ribbon cables get re-connected. My TV works fine and I really appreciate the info.!
You are welcome, take care.