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.
Still a valid one.
Not all opamp models accurately model their power supply current behaviour. This is essential for any amp like this.
Not all opamp models accurately model their power supply current behaviour. This is essential for any amp like this.
..as usual, the Gerber-files are 4free.
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Hello .. yes old thread I know
But I have a pair of these in original condition and all I can is that they work and sound good to me in my music room
But I have a pair of these in original condition and all I can is that they work and sound good to me in my music room
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