General-Purpose Audio Amp

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After several months of off-and-on development and testing (and with some help from Steve AA7U) the well-known general-purpose 3-or-4 stage audio amp by Richard Andersen, KE3IJ (SK) is now ready for prime time. You can use it with all four stages or you can bypass the first stage using jumper blocks.

The amplifier has a 2N3904/2N3906 push-pull output stage, and it runs on 12VDC (with a built-in 9V regulator. A diode provides reverse-polarity protection. If you’d like to skip the usual (boring) LM386 and put out some real power (2+ Watts) using good ol’ discrete components, give KE3IJ’s amp a try.

Schematic diagram (PDF)


PC board only $9.95 Buy on eBay
Kit of PC board with discrete components $16.95 Buy on eBay
Fully assembled and tested (produced on demand, shipment within fourteen days of order). $24.95 Buy on eBay