183d product detector

[KB5MD]

I am wanting to install a product detector into a NC-183D.  Does anyone have the schematic they could email or post which came out in ER #44?  I have a collection of several years ER but that
issue is missing.  I believe it used a 6SN7 and was installed in the FM adapter socket.   FOUND IT, THANKS

[k2cu]

you might also consider replacing the CW oscillator with a pentagrid converter tube with appropriate base. Bill Orr had created one for the 51J-4 receiver that use a 6BE6 and worked very well.

[w3jn]

The 6SN7 mod works very well and half the work is done for you already at that NFM socket.  I'm not a big fan of pentagrid product detectors, I've never seen one that produced really clean audio on strong signals.

I had to mess with the coupling cap from the IF to reduce the signal level at the grid of the 6SN7.  As I recall I reduced it to 50 pF or so, but experiment a bit for minimum distortion on strong signals.