Build an AM, CW and SSB Regenerative Receiver for Amateur Radio

I’ve seen countless regen schematics spawned by the good and the great. Wow! — how can such a relatively simple concept garner so much attention and appear in so many forms?  I hardly feel I’ve contributed to the regen knowledge base, but gained valuable knowledge of what I want or hope to achieve in the future.

Regen#5 behaves like any regenerative radio should. The Q-M amplitude control feels precise — almost to the point of being too touchy. But does the regen amplitude control work any better or worse than other designs? I don’t know. The frequency shift associated with changing the Q-multiplier bias is minimal when compared to my other builds.

I applied standard LC VFO temperature stability techniques and felt surprised when I didn’t have to add negative or positive tempco caps to stabilize it. This receiver stays on frequency for hours even when tuning CW and SSB signals.

Regen#5 suffers from microphonics as a SSB/CW receiver — and reminds me of an unbalanced or single-balanced DC receiver without the broadcast band nor in-band AM detection. The scratchiness of my dust-laden, ancient, air variable caps gets multiplied greatly by the sensitive RF chain. I’ll get some Caig Lab’s contact cleaner and have a go on those caps.Still, too, the AM and SSB detector poses compromise — maybe it’s better to run 2 separate  optimized detectors with a switch to pass the signal through the best detector for the desired demodulation mode? I’ve got lots of experiments ahead, and more regen circuit ideas to share but plan to stop all regen work until next fall.