S GAUGE AMERICAN MODELS BUDD CARS--"LED" THE LIGHT SHINE OUT!!

As the title of this post suggests we're going to "LED" the light shine out of AM Budd Streamliners! It ain't that hard to do...really!

EDIT: BEFORE YOU START ANYTHING MAKE SURE THE WHEELS ON THE CAR ARE SCRUPULOUSLY CLEAN! IF THEY DON'T MAKE GOOD ELECTRICAL CONTACT WITH THE TRACK IT'LL DRIVE YOU CRAZY TRYING TO FIGURE OUT WHY THINGS AREN'T WORKING RIGHT! DON'T ASK ME HOW I KNOW THIS. 

First a parts list:

1. You will need rectifier to change AC track voltage to DC voltage so the LED's can operate (they only can use DC). 

2. You will need a capacitor to prevent flickering lights at low voltage. 

3. You will need some mini male/female plugs. 

4. You will need some LED strip lights. 

5. You will also need a voltage regulator. This one is adjustable so you can preset how much light you want your cars to put out. When used in conjunction with the above referenced capacitor you can get a steady flicker-free light effect at low voltage.

6. You'll also need a soldering gun, solder, some double-sided foam tape, and some patience.

Here's the parts:

  I've shown two regulators so you can see the back side  but you'll only use one/car.

OK...let's go. First find a suitable location that let's you spread out the components. Make sure it's padded so you don't scratch the car's paint. I'm using a coach car for this demonstration. The observation car and diner  which I did earlier differed in that it was harder to hide the components. I haven't tackled a dome car yet but I will next week. Here's a typical coach car:

There are four screws under the car. Remove them and put them in a safe place because they will do everything they can to run away:

Here's what you'll see inside the car:

With a black felt pen mark the floor end with an X  and the underside of the shell end with another X so you'll reinstall the shell correctly later.

The green circuit board is what powers the incandescent lights supplied with the car. We will use it for the LED's because it provides a place to access the AC power (on top) and also a place to secure the LED strips (underneath). First we need to remove the 3 bulbs. It's easy. Leave the board attached to the car, pull down on the bulbs while at the same time touching the solder joints of the bulbs on top of the board with a soldering iron. You'll need to alternate on the solder dots while pulling down on the bulbs. When they let go keep them for some other use.

Next you'll attach the LED strips to the underside of the board. Remove the two screws that hold the board to the car. (DON'T LOSE 'EM!). With the underside facing you attach a length of double sided sticky foam tape. Use about a 3/8 inch wide piece and keep it to one side or the other so it doesn't block the mounting holes. Mine was as long as the distance between the holes. Cut an equal length strip of the LED's being careful to only cut at the middle of the copper solder discs every 3 lights on the strip. My strip was 15 bulbs long. If it were mounted in the center it would block the board mounting holes so that's why it's offset to one side:

 Now solder a female plug to the copper tabs at the end. Polarity means everything here to keep things straight. I like to use the red wire to designate (+) DC power. My strip wasn't marked as to which side was (+) or (-) but it's easy to find out. Take 9 volt battery and with jumper wires try different combinations until the strip lights up. Then mark which side of the LED strip is connected to the (+) side of the 9 volt battery. You can't hurt the strip if it's hooked up backwards to the battery...it just won't light.

Here's a close-up:

Now we need to add the rectifier so we can change the AC power to DC power. If you look closely at the rectifier it has 4 legs on it. The center two are marked  with an ~ sign. That's where the AC power will go into the rectifier. The two outer legs are marked (+) and (-). That's DC power coming out of the rectifier.

First reinstall the green circuit board on the pegs of the car. At the end of the board there are two solder dots. Attach a female plug to these two dots. Wire color DOESN'T matter here as the power going in the wire is AC (alternating current). With a little hot glue attach to the car floor the rectifier standing legs up next to the partition at the end of the car. Solder a male plug to the two center (AC) legs. Attach the female plug from the top side of the circuit board to this male plug. We now have completed the path for the AC power to get into the rectifier:

On the outer legs we will attach the capacitor. Think of the capacitor as a kind of a battery. It stores up energy to be released when called on such as on dirty track. Happily it will also supply power to the circuit allowing the LED strip to output light at a level higher than track voltage. The capacitor is also polarity sensitive. On one side you'll see a gold stripe. The wire on that side is the (-) wire. Solder it to the (-) leg of the rectifier. The other wire out of the capacitor is the (+) wire. Solder it to the (+) leg of the rectifier. I was able to hide the capacitor in a partition hole near the rectifier:

Now solder another female plug to the two outer legs of the rectifier. Solder the red wire to the (+) leg and the black wire to the (-) leg.

We're getting close now to the finish line.

Next we will install the voltage regulator. Luckily it is just the right length to match the car partition. Solder a male plug to the "INPUT" side...red wire to (+) and black wire to (-). Mate this male plug to the (DC) female plug coming from the rectifier. Solder another male plug to the "OUTPUT" side red wire to (+) and black wire to (-). This OUTPUT wire is what will mate with the plug on the LED strip. I secured the regulator board to the end wall of the partition with two small screw using the provided board mounting holes:

EDIT FOR THE NEXT STEP:  WHEN I SET THE VOLTAGE ON THE REGULATOR AT THE BENCH I WAS USING AN AMERICAN FLYER 8B TRANSFORMER USING THE ACCESSORY AND BASE POSTS (15VAC) CONNECTED TO THE CAR WHEELS WITH JUMPER WIRES.

The regulator has a tiny adjustment screw on the blue thing-a-ma-bob which allows you to set the intensity of the LED light. I powered up the car with AC and turned the screw one way or another until the strip lit up. I then adjusted it to the light level I wanted (about 10 VDC). To do this I touched  volt meter leads to the regulator outputs until it showed the 10VDC I wanted while adjusting the screw. You may need 6 to 8 hands to do this.

OK with all the plugs connected correctly and the LED voltage adjusted to 10VDC apply some AC power to the car wheels. If all is correct you'll see this:

If not... You'll have to recheck all your work and make sure the solder joints are tight and correct as to polarity where required.

Here's a refresher. The AC power comes from the track through the wheels... into the wires attached to the trucks...into the green circuit board...out of the green circuit board into the center legs of the rectifier...where it is changed to DC power... and exits the two outer legs and enters the voltage regulator (+) to (+) and (-) to (-)...then leaves the voltage regulator and enters the LED strip (+) to (+) and (-) to (-). The capacitor is just along for the ride being used when called on and boosting voltage.

When I ran my Texas Special set at the speed I wanted I measured 6 VAC on the track. The capacitor kept the LED strip putting out light at 10 VDC. The difference in lighting between the factory supplied 3 incandescent bulbs and the LED strips at 6 VAC was huge:

Mark