[Milsurplus] GRC-9 bias battery AAAA

[WA5CAB at cs.com]

I think that you said that these batteries were several years old.  You 
might want to go and buy a new Duracell and check it.  A few years ago, I built 
a part of a BA-41 (the 12V was derived from the external B supply) from 
9-volt batteries.  One of the sections in a BA-41 is a -4.5V bias supply for 
the audio amp.  I determined experimentally that it worked fine on -6 VDC.  So 
I opened up what I think was a Duracell (but I'm not 100% certain of that) 
and turned one of the cells over.  So I had +7.5-1.5 = 6.0 V.  Note that 
this only works if no current is being drawn.  If current were being drawn, you 
would be charging the flipped over cell.  It won't like this and will let 
you know in some unpleasant manner.

The other method would have been to make dummy cells out of brass rod 
insulated with heat shrink tubing.  But fortunately, the amp was happy with -6 
bias, which only took about 3 minutes to create.  Note that you can't get 4.5 
V by the simple method.  If you turn over two cells, you will get 3 V.

In a message dated 04/24/2017 16:53:07 PM Central Daylight Time, 
Kargo_cult at msn.com writes: 
> Another data point: i just dissected a “Eveready Gold” alkaline. It 
> holds 6 AAAA’s but they are loose;
> 
>  interconnects, as in the “Energizer Industrial”, are done by a pads top 
> and bottom that make the connections.
> So the “Duracell Alkanline” is still the way to go.
> 
> -H 
> 
> 
> 

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