[ARC5] Q5'er w/converter - mounting, etc

[Dennis Monticelli]

In my own very limited experience (only 2 receivers), Ian, the BFO
doesn't start up reliably on 24V.  You make not care about BFO
operation or perhaps your BFO tube is a nce strong one.  It would be
simple to test your particular radio to see how happy it is on 24V for
your needs.  Dave's point about capacitor health is well taken, you
will probably replace fewer caps (or none) if you can live with 24V.

I dare say that the converter I put on the rear porch of mine was
solid state.  Just two JFETs and two crystals, running off the 12VDC
filament voltage (my BC-453 came re-wired).  This gave me both 80M and
40M coverage.  I typically use a string of 9V batteries providing 60
to 70V for the B+ because there are usually plenty of half-exhausted 9
volters around the house and the B+ drain is low anyway.   There is
enough oomph at 60V to drive a small speaker through a matching
transformer.  Batteries for B+ and 12V for filaments also opens up the
possibility of portable operation, which I have done on occasion with
this radio.  You could apply Dave's voltage suggestion, stack some
rechargeable batteries and still have a portable radio.

On 4/15/07, David Stinson <arc5 at ix.netcom.com> wrote:
> Good Morning, Ian.
> You can simplify this task; you don't need a power supply
> other than the 24 VDC for the filaments.  If you use an
> external amplified speaker (available for four or five bucks
> on the surplus market), the rig will play fine on that voltage,
> assuming you don't have any extra-bad componants
> ("leaky" caps at 250 volts usually work fine at 28 volts.
> Not always, but I've only had to change a few).
> In fact, if you can live with lower / headphone volume,
> you don't even need the speaker amplifier.
> You can build a little sand-state converter,
> run it off the 24 volts and mount it all on the back deck.
> All the wiring points you need ('cept the antenna / IF in)
> are at the back connector.
> Use a box that matches the height of the receiver cover
> and you can take the guts out of the amplified speaker
> and mount them in there as well, making a neat little package.
> Any gain you feel you've lost at 24 volts to your IF can be made
> back in the converter, but I don't think  that will be an issue.
> Try it- you'll like it.
> 73 Dave S.
>
>
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