TV keeps blowing audio IC

Thought I had this little 9" TV working, but another even tougher problem has popped up. After I originally fixed the set, I ran it for several hours without any problems. Unplugged it and closed up for the night. When I plugged it in and turned it on the next day, the volume was stuck on full blast. I replaced the an IC which serves as the audio OP, volume control, and mute; I also checked for bad caps and cold solder, and measured the voltages on the IC to make sure they were correct. Set works great for a few more hours, again I unplug it and close up. Once again, the next time I power it, the sound is full blast. I only have one more IC left, and I'm not installing it until I know what the underlying problem is! A note about this set; when switched to radio, it uses the same audio IC. The IC is powered by a separate power supply, not from the TV flyback. What am I missing?? BTW please see my previous post "Yoke Replacment" for info about the previous repair.

Reply to
Chris F.
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maybe static charge of crt to speaker or chassis. Check crt grounding if ok and speaker is close to crt run a ground to the speaker frame useing a resistor maybe 1 k.

Reply to
Doug

problem

hours

few

not

IC.

Did you check the voltage of the power supply at the IC?

Reply to
James Sweet

Yup, 12V dead on just as the specs dictate.

full

control,

Reply to
Chris F.

That's what I'm wondering too, since it only seems to fail on powerup. I will check that out.

Reply to
Chris F.

Did you check the voltage at powerup too to make sure it doesn't spike? Unlikely but possible.

Reply to
James Sweet

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