K3HVG wrote:
snip on
the the NC-183D. A previous owner elected to install a product detector
in a typical plug-in can and is inserted into the NBFM adaptor socket.
The receiver-phone switch was borrowed for the selection of the new
detector and the old and new detectors, or so it would appear. Although
it works, I'd like to get it back to stock. If it the switch was the
only issue, it'd be easy but there are other obvious changes. Does
anyone have any info or pointers to where this, or similar,
modification(s) may have been written up? snip
73 de Jeep/K3HVG


Hi,

May 1964 QST had a product detector for the HRO receiver NBFM socket.
(I presume that is similar to to the NC-183D NBFM socket).
The article was by Loren Windom (of "Windom antenna" fame).

73,
Ed Knobloch