[ARC5] Low B+ supplies for BC-454-B RX?

[David Stinson]

----- Original Message ----- 
From: "Roger Basford" <roger at new-gate.co.uk>
Subject: [ARC5] Low B+ supplies for BC-454-B RX?


> Hi All,
>
> I believe that it's quite feasible to run a BC-454, etc from a 50 volts B+
> supply, is this correct?

Your BC-454 will run spendidly on +50 VDC.
I run mine on 24 VDC.
You will have somewhat less audio out.
I use an external amplified speaker
(cheap as dirt from any computer surplus outlet).
In larger receivers, I tack-in a cheap little audio amp
or LM-386 and run it off the filament power.
You will find you have less need to replace leaky caps,
since leakage currents often drop to microamps or less at low voltage
and the cap still works fine without the stress of +250 volts.
I have several that work just fine without changing a single
componant.  I clean switches/contacts, power it up and align
it and away she goes.  Dead short caps and flat open resistors
still need changing, but at low B+ that amounts to a small fraction
of the work that needs doing if you're going to run +250.
And another big plus for me, since I tend to get
"scatter-brained" and get "bit" by high-voltage:
+24 volts don't hurt much.  +250 volts will kill you.

The radio runs cooler and stablizes faster.
Sensitivity is not much affected- at least, not in any meaningful way.
Low B+ in boatanchor receivers is, IMHO, the most desireable
way to run them, providing the enjoyment of using them while
preserving the maximum amount of original workmanship.

73 Dave S.