[Milsurplus] Stablizing a BC-221 that has an RA-133 installed

[J Forster]

Has anyone tried monitoring a known stable modern crystal or the stability of a
BC-221 with a good counter and varying the B+? Surely there must be references
somewhere in the ham literature. There are certainly solid state conversions
with tube replacements builkt into tube bases for the units.

Best,
-John

================

Marty Reynolds wrote:

> > The post-war RA-133 (and PP-79/UR in BC-221-B and -Q) is an AC operated
> > rectifier supply built to replace the dry batteries in the BC-221.  B+ is
> > regulated
> > by an 0D3 (VR-150).  The +150 is dropped to the +135 volts that the BC-221
> > was designed to operate from with a 2500 ohm 1 watt resistor...
>
> long delayed echo
>
> Wonder why so much fuss over running B+ 11% higher than triplicate
> of 45V batteries as designed.  IE 150V right off VR150.
>
> Seems like a tempest in a teapot
>
>    Marty
> ______________________________________________________________