Is it docketed? Could it be just dodgy connections? Otherwise I think you
are screwed. You can use your el cheapo scope if you have the pin outs and
see what is going on, ie where its getting to, also you could measure
voltages to make sure its OK, Is it a cmos device with that age? You might
just have zapped it with static and its a piece of silicon junk now. I mean
op amps are hardly complex, two inputs one output and that is about all.

Brian

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"pinnerite" wrote in message
news:20210106201634.7978823a120bfc4822767851@gmail .com...
Ten years ago I bult a low-noise pre-amp based on a 1970's article in
Elektor magazine.

It used a TBA231 dual op-amp IC.

It didn't work but I did not have time to test all the copper runs etc
before I wa over-whelmed with 'work'.

This week I took it out and started fault-finding.There was one open
connection, poorly soldered. I then checked the power links throughout
the board and they were fine.

Next i connected in a little waveform generator to the input and one of
those timy LCD screened chinese oscilloscopes to the output. Nothing.

So with no shortcircuits, I concluded that the capacitors were OK whch
only leaves the IC.

I do not have another TBA231 or equyivalent but have no idea how to test
the chip.

I am a bit out of date with electronics since my heydays

So any suggestions will be welcome.

TIA






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