[Milsurplus] GRC-9 Bias Battery

[Hubert Miller]

My understanding is that with an expired bias battery, but of course one that still has some DC resistance, the maximum audio output is limited,
for speaker output, and distorted at higher, non headphone level. I cannot remember actually verifying this myself. But the receiver will work with
an expired battery in place.
I sold maybe 4 GRC-9 last year. With each, i provided a small 3 watch cell holder. This holder was about ¾ inch diameter, so it fit well into the
battery space. I bought the holders and cells from China ( naturally, and with some regret of course. ) The holders are quite compact and not
heavy duty at all, but how often do you have to change the cells, at 0 uA draw ? Another thing i got ready to try, but never did, was to use a standard
9 volt radio battery, with a high resistance divider across it to deliver 4.5 to the grid. The divider resistance would be in the low megs and the
divider current, altho continuous, is in low microamps, so the battery can be expected to last a long, long time. I kind of prefer the 3 watch cell
holders i have though.
Richard Brunner pioneered the use of an LED to illuminate the receiver dial instead of the feeble pushbutton operated dial lamp. You interrupt
the B+ line in the receiver and the LED runs in series. This costs you of course ~3 volts from the B+ for the plates, no big deal. I have, i think i can
find, Richard's summary of the process and i will forward it on request, or if it's a small file, i will post it here. I later looked into "string LEDs"
as a further improvement but i never actually put such in a set. I think this style LED has much promise. If you replace the feeble #49 lamp you
will love the lighted receiver dial, no lie. None of these LEDs cost any money; you just might have to buy 20 or so to get 1. You then have the dial
light pushbutton to devote to some smarter use.
I am letting my impoverished brother sell off some of my collection. His attitude is "Sell, sell, sell!" while my attitude is, "Let's think about that a
minute." We sold off 2 of my best GRC-9, one a Hoffman and one from the rebuilds Fair sold, which  was especially picked out. I also foolishly  sold
one for a nothing price at a hamfair, and then sold 2 to a ham radio acquaintance, which i'm sure he flipped, as well as the stack of boat SSB
radios i gave him. Live and learn. I am not a fast learner, but i learn very well, with an indelible memory for some things.
-Hue Miller
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