Thursday, March 24, 2011

NTS&B Two ugly light bulbs for a neat picture

A few years ago, Kathy bought me this neat picture of a 60's diner with parked cars.

The sign and cars all have LEDs in them, and it really looks sharp with the room lights on.

When I hung it in the train room, I discovered the problem that when you shut the room lights off, all you see is the LEDs.

The diner picture was taken at dusk, and the walls behind the picture are white, so it is very dark and hard to illuminate picture without lighting the whole room. After multiple attempts I finally decided to use a K-Line 2 light spotlight tower (#22326), and replace the bulbs with 2 Radio Shack 276-0017 high brightness (7000 mcd), low angle (30 degrees) LEDs. The result is shown above.

I started out with 2 burnt out light bulbs. I broke the glass out of them using a pair of pliers held in a trash can and wearing safety glasses. I put a piece of small diameter heat shrink over the wire going to the center post of the socket and soldered one side of the LED to the wire. I placed another piece of heat shrink over the other leg of the LED, and soldered a 2.2 K Resister to it. Then I soldered the other end of the resistor to the outside of the socket. I did not shrine either piece of the heat shrink, which allowed me to push the LED into the socket while keeping the wires insulated. The results was one ugly light bulb !!

I then screwed the LED into the light tower socket. I cut a piece of large diameter heat shrink (shown), and then placed it on the LED (no heat) so only the front of the LED is visible.

A view of the light Tower from the front. Notice the LEDs are very focused, with very little light from the reflectors. The left one does not have the heat shink sleave applied, and there is still very little light bouncing off th e reflector. The tower is in approximately where it will be permanently located.

View from side of tower with sleaves over both LEDs. Notice there is hardly any light visible from the side of the LEDs.