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

[WA5CAB at cs.com]

Clete's comment makes sense.  It costs a lot of money to produce TM's.  The 
RA-133 fits every BC-221 model built except for the BC-221-T1 and the two that 
the PP-79/U was built for, and I'm not sure it wouldn't work in those but it 
wouldn't be a drop-in.  Plus the TS-173, et al.

My post was a comment from personal experience.  I have 60+ BC-221's and 
maybe a dozen RA-133's.  And all of the RA-133's suffer from the B+ dropping 
resistor going high.  The zener costs no more than a new resistor and it definitely 
improves the stability of the instrument.  However, I won't make the mistake 
of posting anything like this again. 

In a message dated 9/11/2008 3:25:40 PM Central Daylight Time, 
whitaker at pa.net writes: 
> de WB2CPN
> With 150 V they would have to change all
> the voltage readings in the maintenance
> manual.  That's for every model that the
> AC supply could be squeezed into.  Also,
> a series resistor helps with regulation.
> 73  Clete

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480   
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