[Milsurplus] Re: Future parts availability

[David Stinson]

----- Original Message ----- 
From: "Arden Allen" <gumbear at pacbell.net>
Subject: Re: Future parts availability


> > Resistors with wires on them are going to get scarce eventually. ...
>
> I expect the hottest topic then on BA will be how to "roll your own" out
of
> chip resistors.  Stay tuned.....  (-:

I think people at that time might consider my suggestion that
many of our sets can be run quite well on deeply reduced B+,
eliminating the need for most recapping and parts changing
and preserving the original parts.
I'm working on a receiver that used 250 VDC B+ and 12 VDC fils.
I tucked a little 12-volt audio amp from an old
set of computer speakers (costs $4 from a surplus outlet)
inside and the radio is working well on 50 volts.
Next experiment is to see just how low I can take
the B+ and still get acceptable sensitivity and reliable BFO operation.
I've heard all the arguments about "cathode poisoning" or whatever
it's called, and I don't think it's a real concern in BA receivers
that are run, at most, a few hours a week.
Even if it does happen, it will take a very long time at that duty
cycle and changing receiver tubes is easier than replacing tired,
60-year-old caps that were blown up by running them at
high voltage levels.
Biggest difference I see, other than the cheap little audio amp,
is that the set runs cooler and stablizes faster.
This is the only way I would consider running my rare sets.

Getting a BA transmitter to work on reduced B+...
that's going to be an interesting challenge ;-).

73 Dave S.