l37wd14 New Caps Still no Sound

[reliantkcar]

I just got this l37wd14 for 10$ last night.

video works fine but sound only works for 5 mins

I found 3 bulged 16v 1000uf caps on the power supply

I swapped em with 35v 1000uf caps from radio shack

still only 5 mins sound and the audio output doesn't work at all

I turned over the powerboard and saw some burn

any ideas what to change next??????
(excuse my poor soldering skills my iron is from WW2 literally)

[tom66]

Re: l37wd14 New Caps Still no Sound

RadioShack caps could be causing the problem, they can often be worse than the originals. I would highly suggest Panasonic FM/FR/FC or Chemicon available from Digikey.

Do you have a digital multimeter?

Have you tried heating up things to see if the problem occurs quicker when you heat a particular area?

[reliantkcar]

Re: l37wd14 New Caps Still no Sound

any idea what that burn under the transformer means? it seems like changing the caps did nothing. yes I have a meter what should I probe?

[tom66]

Re: l37wd14 New Caps Still no Sound

Check the various output voltages from the PSU and see what they read.

[budm]

Re: l37wd14 New Caps Still no Sound

That is the RC Snubber circuits for the Transformer primary winding side which is driven by the Power MOSFET. On the left (cold side), you can see over heated RC snubber circuit for the rectifier Diode as well.
What brand is this l37wd14?

[reliantkcar]

Re: l37wd14 New Caps Still no Sound

RCA brand. the sound barely works for 5 mins then crackles out and the audio output never works. there is a digital rca audio out but i have no wat to test

[tom66]

Re: l37wd14 New Caps Still no Sound

I'd try heating up things first, try and see what is failing when it warms up.