[Milsurplus] Dial Light for GRC-9 Receiver

[Hubert Miller]

I will add this, tho it might not be to some people's taste. On a bayonet base socket I had, from some disassembled equipment, I slightly bent one of the "holding flanges" or "ears" at the top of the socket.
I very slightly bent it inward to try to engage the threads of the screw base bulb. I was able to force - fit a screw base bulb into this socket and it held; yes it actually held. With the LED you will practically 
never need to change the bulb, so I think this is practical; you don't have to concern yourself with how easy or hard it is to replace the bulb. HOWEVER I have not executed this inside the GRC-9 where there
is very little room to work !

A seller of such bulb is 
https://www.ebay.com/itm/223625154188
If you need to search Ebay for such item, search on:   E10 LED 1.5 volt 
The screw base is the negative contact, which is good for us.
If you want to look up sockets, you look for " E10 socket ". Ebay has them for no money in wire leads style. I am wondering at this point, maybe we could solder a stiff wire to the base of the bulb and use this
both as ground wire and to hold bulb in place. 
Thanks to Richard Brunner for his many experiments to prove out these ideas.
-Hue 

>Subject: Dial Light for GRC-9 Receiver

Another option:  There is available a small LED which works very well on
1.5 volts, identified as "222 E10 base 1.5-3 volt LED." It's a screw base.  It starts giving light at 0.5 volt, good output at 1.0 volt, plenty more at 1.5 volts, and runs very well on the 1.5 volt filament line.  Leave the original lamp socket in place, but remove the bulb so it doesn't shadow the dial.  Run the leads through the hole in the chassis that the original lamp lead runs through, and solder to the filament line.  Position the lamp to illuminate the three bands on the dial, and hold as you wish. Mine is merely held with tape, and seems satisfactory.

There are some miniature electronics in the base, and wrapping an antenna lead around the lamp I heard very weak harmonics every 18 Kc, but installed in the receiver nothing is heard.

Richard, AA1P