I applied a sine wave to the input of the amplifier, but on Pin 6 of IC1 I got an extremely distorted wave. it appears to me as if there's something wrong with the negative power supply or something, but that's was fine. I tried replacing T1 and T2, but to no avail. Whe I remove IC2 and IC3 the problem was solved so I thqught one of them must be broken (didn't test them). I just replaced them with new ones, but the problem remained. I swapped IC2 and IC3, but the problem was the same (neg.side distorted).
What do you guys think could be wrong here? I was thinking about oscillation or something, but like this?? no way!
Peter
What do you guys think could be wrong here? I was thinking about oscillation or something, but like this?? no way!
Peter
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The amplifier is probably unstable due to it's low gain, I expect R4 is actually meant to be 1k or thereabouts. Try changing R4, remember you will need a much lower input signal since the gain will be much higher!
Gains of 20-50 are typical for power amplifiers and I'm sure the velleman kit had reasonable gain when I used one many years ago.
Gains of 20-50 are typical for power amplifiers and I'm sure the velleman kit had reasonable gain when I used one many years ago.
Uhm, this is a very old thread...
Yeah, spotted that after I posted!
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