Sanyo TV , Garbled sound

[Karen Ray-Stewart]

I am working on a Sanyo AVM-2547U Tv , all of the electrolytic caps
check out fine.There is no audio when you power it up. when it runs for
about 10 min. the audio slowly comes back, but it is garbled. their are two
IC's TDA 7132 audio output IC,s I freeze sprayed them but no change. I think
it could be the tuner? there is a 2 watt resistor in the supply right beside
it maybe causing this? any suggestions?

James

 

[JR North]

Scope the audio path into and out of the stereo decoder, to the TDA 7132
output ICs when cold started and no audio. If OK, check the I/O cicuits
of the TDA 7132 chips.
JR

 

[Karen Ray-Stewart]

Hi it turned out that it was the LA7673 IC when you hit it with the
spray the audio level drops.same with the signal. I always thought that
these IC's either work or don't work. IE no video,color, had a problem with
that one a few years back, i guess it is a partial breakdown of the IC.

James

 

[Karen Ray-Stewart]

Cool webpage,love the audio speakers!! I have been running a buisness in
repairs since 1994

Hi it turned out that it was the LA7673 IC when you hit it with the
spray the audio level drops.same with the signal. I always thought that
these IC's either work or don't work. IE no video,color, had a problem
with that one a few years back, i guess it is a partial breakdown of the
IC.

James

 

[JR North]

My neighbors hate them
JR