My version of the
George Grammar Superhet
from Feb 1941 QST

This popular little rig came out in QST as a "Junior Constructor"project.  The original scheme used two tubes, a 6K8 and a 6C8 as a regenerative superhet with plug-in coils.  Quite simple to build and a nice effective circuit.  I took a few hints from the  project page of Niel Wiegand, W0VLZ  and added some of my own.  I wound up with the 6K8, a 6J7 detector, 6SN7 BFO and 1st Audio and a 6K6 audio output stage.  Power supply is onboard.  I did not incorporate the series crystal filter.

I went thru an earlier version using a 6X5 half-wave supply and no 6K6 and it was begging for less hum and more oomph.

This was a nice project.  It performs well and is plenty adequate to use for routine operation.

-WX4A Sparkbench, Jan. 2006

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