[Milsurplus] BC-474A Receiver Conversion

[Ian Wilson]

Just to make things clear, this receiver has already been converted - not by
me!
My interest in a conversion document is to understand what might have
been changed that isn't immediately obvious from the wiring changes
needed by the tube subs.

The original is long gone. The 'conversion' completely replaced the front
panel and the transmitter, apart from some recognizable components
such as the multitap tank coil. The outer case is in nice condition.

Since the damage is completely irreversible, I thought I might some day
at least complete the transmitter and put this rig on the air. Then it
wouldn't
be a complete waste.

73, ian K3IMW

On Sat, Oct 23, 2010 at 7:50 PM, David Stinson <arc5 at ix.netcom.com> wrote:

> One tip for anyone hoping to get a 474 receiver working:
> Like many battery operated sets, do NOT ground the B-.
> B- floats to give bias to the audio output stage.
> Grounding the RX B- will instantly destroy the audio
> output transformer by opening the primary.
> That's why 90% of the 474s you see have open transformers.
> While an "ARC-5" output transformer is not a "good"
> substitute, it is readily available and does work.
> Tight fit but can be done.
>
> Oh... and if I had such a "conversion" document,
> I'd burn it and scatter the ashes.  ;-)
> 73 Dave S.
>
> -----Original Message-----
> >From: Ian Wilson <ianmwilson73 at gmail.com>
> >Subject: [Milsurplus] BC-474A Receiver Conversion
> >
> >I have a conversion of a BC-474A that includes what seems to be the
> original
> >receiver, but modified to use indirectly heated tubes.....
>