As a refreshment after all my recent home brew activity I built a nice little direct conversion receiver kit from QRP Kits aka "Pacific Antenna".
It's a classic NE602 + LM386 direct conversion receiver as described in Experimental Methods for RF Design. I've built these before. This version ads an RF bandpass filter to the front end and has an unbalanced audio chain to the LM386. It drives headphones just fine but is a little soft into my bench receiver.
Even though it only covers a small portion of the band - you move that portion with the trimmer capacitor - tuning is very sensitive and they do suggest that a multi-turn pot would be a good idea. I find it drifts a bit. Some of the supplied capacitors had very tiny and indistinct markings but the kit went together well and it worked on first power up.
Here it is receiving a parks operator:
The documentation is good and available on the web page. My kit arrived here in Melbourne, Australia, three weeks after ordering. Pretty good.
With a bit of board trimming I was able to fit the receiver into a low cost compact case.
"Socketry" this is called.
It seems more stable now that it's boxed up securely.
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