[Milsurplus] bc-348 design question

[Jim Haynes]

On Mon, 12 Dec 2011, Al Klase wrote:
>
> As Robert Downs points out, this radio was designed 15-20 years before
> SSB was a factor.  So trying to make it into an decent sideband receiver
> is a fool's errand.
>
Well I did it, once, but the details would make today's preservationists
cry.  The impetus was an article by W6NRM in CQ magazine about his "Q5-er"
He built a circuit that fitted into the dynamotor space.  It converted
the 915 KHz IF down to 85 KHz, passed it through the IF transformers of
a Command Set receiver, the 200-500 KHz model, and then converted it back
to 915 and reinserted it into the IF system of the receiver.  I had a
bandpass filter I had picked up in a Chicago surplus store.  It was bigger
than the whole dynamotor space, so I attached an outboard chassis to the 
back of the BC-348 and duplicated Bob's idea using my filter.  By bringing
the frequency control for the up-and-down conversion oscillator out to the
front panel I had passband tuning.  Since I had plenty of room on the
added chassis I put a product detector back there.