can someone please help with this problem ?

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i blew the op-amps in my op-amp based amplifier by attaching the powercord with the amp switched on.
doh !
pretty blue spark though.
i replaced all caps/diodes and resistors on the pcb with parts of equal values but of higher quality.
i couldnt replace the original tda2030a op-amps.
i have tried lm1875 and sk18752 op-amps now.
the amplifier has a pot that is also the on-off switch.
as soon as the power is switched on the volume is not blaring but louder than moderate with either of these chips.
it used to attenuate to silence at the lowest setting.
there also seems to be no difference in volume until i turn it about 90 degrees.
a friend accidentally blew 1 of his tda2030a chips in the exact same amp and when he replaced just 1 channel with the lm1875 he had no trouble with his pot like i do now.
could the pot have been damaged by the surge that blew the chips ?
i tried measuring the pot for log/linear but it read like linear and i dont know if that is because it is damaged or if it really is a linear pot.
any help would be greatly appreciated as i can no longer listen at low volumes while the family is sleeping.
thanks.

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Topic - can someone please help with this problem ? - snkby 22:50:20 05/17/01 (4)

Re: can someone please help with this problem ? - kye 23:24:58 05/17/01 (3)

thanks kye ! i had it out of the pcb already when - snkby 01:04:36 05/18/01 (2)

Re: thanks kye ! i had it out of the pcb already when - Comm-Tronix 20:11:52 05/18/01 (1)

thanks comm-tronix ! will open it up and - snkby 00:41:29 05/19/01 (0)

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