80m or 40m Simple Regenerative ReceiverDESIGN

L1 is a small T50-2 (red) toroid with around 18-20 turns (40m) or 35-40t (80m) on the main winding connected to the FET with a single turn coupling loop for the antenna connection. The tap is about 20% up the main winding. C1 is adjusted to set the radio into the 40m band and C2 then acts as a fine tune within the band. You can check the frequency by listening to the frequency radiated when the stage is in oscillation. By changing L1 and C1/2 other HF bands like 80, 30 or 20m can be covered. Experiment! C4 is adjusted to get the circuit to just regenerate.

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