2
Score
pollytinto
39k
Asked
Has picture but no sound.
This tv is giving me a profound headache..story was: picture no sound. Ordered replacement board (the board to which the speakers connected to)(repeat several times) all had other faults but no sound restored! Decided to fix original board..found 2 blown caps. Still no sound. Up until today I was convinced that the problem must be on the board because other boards gave different problems. Have searched all over board and can find no other faults so bought this final board..still no sound! I initially checked the 2 speakers for continuity and moved on. I know nothing about tv's or speakers apart from what I'm learning as I go. I think the speakers must be the problem but no idea really how to test them/repair them.. the volume bar on the display moves up etc, have been through all the settings/menu-no help at all. Any ideas??
1
Score
Fred
115
Answered
Quick check of speakers: disconnect from board output and momentarily connect a 1.5 volt battery. You should hear a "pop" when connecting and disconnecting, if the speaker is good. Speakers unlikely, however. Two at once indicate blowing the speaker coil due to power overload, which also is unlikely from a TV audio amp.
Each speaker is connected to an independent stereo output from a dual channel amp, yet each side has the same problem. Blown caps indicate a power problem. Multiple board replacement without problem resolution indicate a problem external to the board.
If it's the power supply, it's an output providing voltage just to the audio circuits. You probably need to troubleshoot -- replacing all components multiple times can get expensive.
no pops. so no power to the speakers. looked all over the input board, all caps/chips/thin
Can you hard wire the internal speakers to any other external playing device like a radio? Can you make the TV play a tone and test the potential and/or current going through the speaker wires to see if power is getting that far?
Phillip Takahashi,
I've been racking my brains over what I could rig these speakers to...have dug out an old transistor radio. How easy do speakers stop working???
pollytintop,
pollytintop, try it the other way around. Use an old speaker, yes even the one from your transistor radio would work. Connect it to your TV via a set of alligator clamps. That way you can check if your board supplies each channel.
oldturkey03,
clever man! never thought of that..truly am a little deficient in the thinking department lately.
pollytintop,
That would only diagnose his board. I was thinking of trying to see if the speakers are dead for some reason. I honestly cant think of any reason the speakers would be dead if they passed a continuity test...but you never know!
Phillip Takahashi,
Phillip Takahashi, absolutely and I do agree with you. But I figured the deduction you can make, that if the board works with another speaker, it will eliminate the board and rule in the speakers as a fault. I somehow have a gut feeling that the speakers are okay, since it is very seldom that multiple speakers ( I assume it does have multiples) go out. Of course nothing is impossible and worthwhile to check out. Pollytintop, I am still working on a circuit diagram for that particular model....:-)
oldturkey03,
Thanks guys..yes it has 2 speakers.. I think it's another duff board-people sell them from broken LCD tv they get cheaply (maybe the sound goes and they put the boot in to get it sold for parts?) Have had this in my front room for 2 months trying to get it sorted...fedup.
pollytintop,
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