This (above) is a general Shortwave Superhet receiver I built over the winter. I chose to go modular so I could interchange some of the modules and make easy repairs and changes to the circuits. I used discreet components and only 2 integrated circuits. I built a Colpitt's buffered oscillator which is remarkably stable, a Gilbert Cell Double Balanced Mixer, a high pass filter to filter out local AM broadcast station. The IF chain uses an old classic collins 455 khz mechanical filter amplified by a J310 feeding into an MC1350P IC... It's using 2 germanium diodes as a detector feeding into an LM386 output amp. It's very, very selective and sensitive. I added a 455 khz BFO (lower right in pic) the other day to tune in SSB and CW. This has been a fun experiment.
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