[Milsurplus] Another GRC-9 dial light option

[Hubert Miller]

Richard Brunner described the procedure for wiring a bright white LED in series with the receiver B+ for a vastly improved dial lighting.
Here is another LED option.
You need to buy a "single battery LED" as I described earlier. This small screw base bulb is the same size as small flashlight bulb #112
and like the incandescent, runs off 1.5 volts, via the tiny "joule thief" oscillator inside. You also need to buy a screw base lamp socket to
fit, one with wire leads only, no mounting flange. This socket can be wired via a stiff wire right to the existing bayonet socket leads, the
stiff wire suspending in place the new screw base socket. The pull will be about 80 mA, and i think it will be switched as the original
function went. You position the socket for best projection of the light. With this lamp, the dial actually looks white, not yellow. The
numbers stand out. I tried to photograph this but my camera cannot deal with the bright to dark extreme contrast, so no dial numbers
show.
You may rightly be asking, does this joule thief, probably operating in the high tens of kHz, generate RFI. I don't know ! I do not have
enough playground time allowance right now to fetch my receiver PS. Worst case, if it generates RFI and you leave in place the original
switching, it only RFIs while the button is pressed. For now, I am leaving RFI investigate to the lead scientist on this project, R. Brunner.

I think I will be satisfied, however, with the method Richard described, as it adds zero current drain for a satisfactory light level.
-Hue

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