X-Mozilla-Keys:                                                                                 
David Carter wrote:

Paul,

What is a "variable regulator" as differentiated from a "very low power
pot"?  Did you mean a single "variable regulator" for several LEDs and an 75
ohm droppng resistor on each LED?  Or, does it take a #2 variable regulator
plus a dropping resistor for each LED?

David Carter

Its a solid state device and it looks just like the three
terminal device in the drawing. It has four wires instead of 
just three. One is 12-14 volts input, another is regulated voltage
out. One is ground and the other goes to the center tap of
a pot. The top of the pot is connected to the output wire.
the bottom of the pot is connected to ground. Unlike the usual
pot to dim the instrument lights this pot carries very little
current so it runs cold. Once the pot is set the output voltage
never varies regardless of the amount of current sucked out 
of the regulator.

The part number is Nat. Semi. LM2941 TO-220 package 1 AMP.
About $3 in the Digi Key catalog.

One... 1 amp regulator will handle about fifty 0.02 amp LED's.
Each LED needs a 1/4 watt 75 ohm dropping resistor.

Hold on guys I think I have a better idea with the goose neck
LED lamp trick. I am building one as we speak. The LED circuit will
be exactly the same. Looks like 3/16 inch  hardware store copper tubing
works great as the goose neck. A standard flare fitting can be used
to mount it in the instrument panel. the light will go precisely
where you want it and a minimum amount of light will be needed.

Paul Lamar
 
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