Magnavox has a black screen & buzzes - HELP

magss

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Jul 3, 2013
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My old Magnavox Model# 25TSC6 0101 has a black screen & buzzes (is volume controllable). (SN: 39890674, Purchase Date: 11/13/94)

I have it plugged into a surge protector, but we've had a LOT of storms this year. I've heard they can only take so many hits B-4 they no longer work. This did not happen immediately after a storm, but a few days later. ?

I read one blog that said this is a power supply problem, they replaced a 330fu 10V Cap & it works like new, though theirs was a different model.

I have the power supply pulled out & to do so, I had to unplug some of the connectors. I can't find a Cap that looks blown. There are a couple spots below resistors where the (tan colored) PCB looks brown or slightly burned, but they're stood up off the board & they look intact.

Another said it could be a Xfmr, however, there are 3 & don't know which one it would be.
1) Lg one - PCB label is T401 & Xfmr label is 00300823-1001, EIA 232, 94343 L1T6, Mexico.
2) Sml/Med one - PCB label is L400 & Xfmr label is 915-7M R.
3) Sml one - PCB label is T501 & Xfmr label is 913-101 & the next # is faint & looks like 90363 LATS - or maybe - 94363 L4T6?

There is a label on the power supply PCB that reads: Model# EMB525B004.

I'm really spoiled by the 'Smart Sound' feature & can't afford a new TV right now (haven't worked in over a yr).

Can you please give me your thoughts on the cause or what to try to diagnose? Is there anywhere I can get a hold of a schematics for this near-antique? I do have a multimeter, just don't know quite where to start.

Thank-you.
 
Solution
Plenty, I know you would like to fix it. But choose your battles wisely, the ones you can win. Maybe you can find a parts only, EXACT set on E-bay and swap boards out, but I would not go any further.

magss

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Jul 3, 2013
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Yes they are. I do have some electronics experience, as well as the tools/supplies to do the job. Do I need to remove them to check for fried wires? If so, which Xfmr is the best to start with, what pin # combos do I test for & what should they read if there is a connection?
 

ur6beersaway

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Apr 18, 2013
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Replacement parts will be impossible to find, exact size & volt ratings. The set was obsolete when you left the store in 11/94. Anything half as*ed will go on fire, or run unreliably with endless issues. You got your money's worth. Please purchase a new set. You will be happier in the long run. Cheers
 

ur6beersaway

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Apr 18, 2013
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Plenty, I know you would like to fix it. But choose your battles wisely, the ones you can win. Maybe you can find a parts only, EXACT set on E-bay and swap boards out, but I would not go any further.
 
Solution

magss

Honorable
Jul 3, 2013
4
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10,510
So, I take it you're sure it's the Xfmrs & not a Cap. or other component that's cheap?

I do like puzzles & tend to get into a vendetta mode, then end up spending more $ in labor than parts.