homebrew ssb receiver part 2 – audio amp

For the next step of my homebrew direct conversion receiver is the audio amp. I used this schematic from N6QW’s Simpleceiver posts.

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Here is the amp mocked up on a breadboard.

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It worked, but not very well. There was a lot of noise and static. At this point, I thought about switching over to a LM386 based amp, but I went ahead and soldered it up on a piece of copper clad. I used a dremel and an engraver tip to rough out a few squares. This is the first time I’ve put together a circuit on bare copper clad. Next time I’ll plan the placement a little better. I cut out a few squares that I didn’t end up using and I probably could have shrank the footprint down quite a bit for a more compact board.

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Here is the board all soldered up. It sounds much better. I hooked it up to the kiddo’s tablet and recorded a little video of it working.

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