Dave, AA7EE, has a really nice blog article about his experiences with regen receivers. He writes about a regen kit he built as a kid (pictured above) and goes on to describe in beautiful detail a regen he built recently using a combination of old tech and new tech:
I agree with Dave when he notes that regens are unfairly thought of as mere novelties. My old "King's Speech" regen (below) is a very useful shortwave listening receiver and could easily be used for 40 meter CW contacts. It is even stable enough for SSB.
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