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Lem Morrison's Regen Set

Here are details on Lem's 1AD regen set. Besides the great workmanship, the circuit has some interesting features.

Notice the use of toroids, which tend to be self-shielding. Also note that this set is double-tuned, with a link coupling for the antenna.

Look at the coupling between the two tuned circuits; by capacitively coupling them with a cap to ground, the selectivity at the higher end of the band is increased. This coupling does not work as well on a crystal set, since a DC return is needed, but is fine for an active set.

Lem's Regenerative Radio

Front view of set

Lem's Regenerative Radio

Top view. Note that the black plastic front is backed by a
metal shield to minimize hand capacitance effects.

Lem's Regenerative Radio

Front view of set

Lem's Regenerative Radio

Updated schematic using 12DZ6.


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