TerryJ wrote:
I am considering adding a product detector to my S40A. Has anyone used a
6SN7 to replace the 6J5 BFO and feed the IF signal to the grid of the second
triode with the cathodes tied together? The original oscillator circuitry
would be wired to the first triode. Audio from the plate resistor of the
second triode (after IF filtering).

No, but I do have an SX-99 with a product detector already installed in it,
which I have no real need for any longer. It has a Collins mechanical
filter of unknown width and extremely low audio output. I think it was
originally done according to the QST article but I am not sure. It's
definitely a project set but make me an offer.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."