Bench test amp

Everyone should have a cheap and dirty test amp on their test benches.

Build it in a plastic box, run it on battery power for safe grounds, add a couple of multimeter type test probes and you can probe every stage of an amplifier from input to output to find out where the signal drops out. We aren't concerned with high fidelity, distortion doesn't matter, we just want to know if there's audio there or not.

The thumbnail is for a really easy to build one. Most of the parts can come from your junk box. Nothing fancy.


  • test amp.JPG
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