[Heath] Replacing dial lights with LEDS in SB-102

[Bill Cromwell]

Hi,

I couldn't take the suspense so I went out in the shop and plugged in a 
12 VAC transformer and put an appropriate dropping resistor in series. I 
lit up the LED with no losses, fires, smoke, sparks or any other drama. 
I think the LEDs in the original post are made up in an assembly to go 
right into an existing lamp socket and so they should already include 
whatever series resistor or other diodes are needed to make it work at 
the 'design' voltage. For use of those, pay attention to the 
manufacturer's instructions. For the circuit that needs to be balanced 
an additional parallel resistor may be needed. Or maybe not. Did 
somebody mention 'resistance wire'? I use raw, naked LEDs in my projects 
and I have to be responsible for any polarity and current/voltage 
requirements. I haven't lost very many in all the decades. When I did I 
found I had just picked up the wrong parts and caused the accident that 
way. Ohm and his law are you friends. More milliamps = brighter LED up 
to the point of failure. Then - *blink*. Now I will have to rig up 
something safe to have in the same room and plug the LED/resistor in the 
AC power line. I ain't doing that with bippie leads and fingertips!

You might make a hole (or holes) in a plexiglass sheet and insert the 
LEDs/bulbs in the holes. The plexiglass sheet might diffuse the light so 
as to illuminate your dial the way you want. Some automotive dash panels 
have been illuminated that way in the past (maybe they still are).

Good luck with the project.

73,

Bill  KU8H