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Mine has 12-V incandescent automotive bulbs. I run them from a Radio Shack 12-V power supply with a "cigarette lighter" socket on it that is designed to allow a car type device to run off of 120VAC; like to test a car radio in the house on a work bench.

For remote control I have used two different methods, but neither are like you are wanting. I put an Edison base (a light bulb base with a plug outlet instead of a light on the other end) into my garage door opener light socket, and then plug the power supply into it. When the garage door is activated the opener "lamp" circuit turns on and that then powers the flasher circuit until the garage door opener lamp circuit times out.

The other remote method I have used is a Sears 120V Remote Lamp controller. It is a small receiver and relay in a box with a plug and socket and a small handheld/pocket transmitter that toggles the relay in the receiver. I have the neighborhood kids convinced the grade crossing lights are voice activated and it only works with my voice. I have the control in my pocket and click it while saying "Lights On" or "Lights Off". The kids stand out there all day trying to mimic my voice to get the lights to work. (I allow it sometimes by clicking the button at random times!)


If you don't have a RR Flasher module to operate the lamps you can use a car Turn Signal Flasher and a 12V SPDT Relay (Automotive Horn relay)... but the circuit is a bit strange.

Automotive Turn Signal Flashers are strange beasts. They contain a heater that heats up when current flows and when it is hot enough it "shorts out" the heater. Usually two bulbs (in parallel on the car, front and rear turnsignal lamps) are in series with the flasher. The two bulbs draw enough current to heat up the heater, but with the heater in the circuit there is not enough current flow the cause the bulbs to light up. When the heater is hot enough to trigger the short, then enough current flows to light the bulbs. The heater then cools enough to open the short and the bulbs go out and the heater gets hot again to the point where it shorts itself out again. If you look really closely at your cars turn signals you may notice that the bulb glows really dim and then gets bright and goes back to dim... that dim part of the cycle is when the heater is heating up and the bright time is when the heater is shorted out and cooling off.

In my circuit the relay is a Single Pole Double Throw (SPDT) and was supposed to switch between the lamps. When the turn signal flasher toggled that would toggle the relay and the relay in turn would select one lamp when de-energized and the other lamp when energized. That was my initial idea anyway!

BUT! The relay does not draw enough current to let the flasher heater get hot. So, I had to wire one lamp in parallel with the relay and that one lamp and the relay do draw enough current. You could use a SPST relay if it is a Normally Closed (NC) relay so that when the flasher energizes the relay it turns OFF the lamp is is controlling, but that type of relay is rare and a SPDT is readily available, you just don't use the Normally Open (NO) contacts.

Now to complicate matters! I just built a miniature set of Grade Crossing Lights... set to demo them at the next CVGRS meeting TOMORROW (Sunday)! So your question was quite timely!

I used LED type replacement trailer lamps for this model. The LED lamps do not draw enough current to activate a cheap Automotive Turn Signal Flasher! I had to use a 50-Watt 5-Ohm resistor in parallel with the relay to draw enough current to get the thing to work. Unfortunately, this resistor gets REALLY HOT! (think how hot a 50-Watt light bulb gets!)

I am trying to find a different automotive flasher device that will work on lower current. I also am trying to find what kind of flasher is used on some cars that have front and side lamps that flash alternately... that would eliminate the need for the relay! I know I have seen cars that do this, but I don't know what make/model/year to tell the AutoZone clerk so he can sell me one! I have seen three different vehicles in the last week that had the front and side bulbs flashing alternately, one was a pickup truck and one was a small compact car, neither did I see long enough to get a make/model ID (I was going the other way in traffic and I don't recognize cars all that well... I was lucky to be able to say one was a "truck" and one was a "car"!). The 3rd vehicle I was able to at least identify as a Jeep Cherokee, but I have no idea the year.

If anyone knows what Make, Model and Year car has the alternately flashing turn signals, please post it here and I will attempt to see if the device will work with LED type lamps. THANKS if you can!

So far my "Prototype" miniature grade crossing flasher lights have cost me about $150 to $200, but I think I can get that down to less than $100 once I decide on what are the best sources of the parts are. The most expensive parts have been the electrical box to hold that HOT resistor and the PVC conduit elbows and such used for the pole and cross arm to hold the lights. The rest is pretty cheap... including the relay, flasher and lamps. I am sure better and cheaper parts are obtainable.

I will post a YouTube video "soon" of what I have.
 

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Both of my crossing lights (the real one and the miniature one) flash at a fairly nice uniform alternation rate... maybe I have been lucky getting the loads balanced for the particular flashers I have used. (I did burn out one flasher on the 1:1 real set one time and bought a physically larger replacement... not that they means it is a better one or will last longer).

I just took more video of both of them and will attempt to get something on YouTube by this evening.
 

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The cross-bucks are 2-inch self adhesive vinyl letters stuck on white styrene poster board (1/4" thick styrene sheet with paper on both sides) and sprayed with a rattle can clear coat.

I made the black signs using the Windows PAINT. It didn't make the letters as large as I wanted so I used the stretch function to increase the size to what I wanted. Unfortunately, that function then left the edges of the letters a bit jagged, so I smoothed the letters manually with the pencil tool. Then I decided I wanted white letters on black so I did a flood fill of the background with red, then filled each letter with white, then refilled the background with black... (would of been a bit less tedious if I had thought ahead and set the foreground and background color before I entered the text!). I then printed the black signs on my laser printer, cut them out and used a spray adhesive to glue the paper to some black styrene poster board. Then I sprayed the whole sign with the same rattle can clear coat. I bought some 6-mm jewels at Michaels and a couple of boxes of "glue dots" (a long strip roll of wax paper with 5-mm glue spots every inch) and spent one evening picking up one jewel and sticking it to one glue dot, after making a dozen or so of these I then picked the glue dot/jewel off the wax paper strip and stuck it on the letters.

I have not yet assembled a parts list (I bought way too many parts that didn't work and I have not pared the list down to just the ones I did use). Most parts I got at the hardware store. I only had to fabricate a couple of parts from scratch and drill a few holes in some of the hardware store parts, but even the ones I fabricated could be something again from the hardware store. Many substitutions could be made in the hardware.

The lights are replacement "Trailer Lights" from Harbor Freight. The pole and fittings are gray PVC electrical conduit (which might be a bad choice since I am detecting some leaning/drooping of the pole). The cross arm is attached using two "T" fittings, but I am sure a "+" fitting is available "somewhere", but not at MY local hardware store. A lot of the fittings were very expensive (the 4X4 electrical box was $19.95!) and some substitutions might be cheaper. I happened to have the 3/4" thick aluminium plate on hand... other things could be used... I even considered just putting a pipe out the bottom to stick in the ground instead of the plate I used (might be cheaper too, the flange on the bottom was $9.50.

The 5-Ohm 50-Watt resistor I got from Iowa Radio (a local electronics shop), I don't know if Radio Shack has anything like that in stock, but I assume it is available via the Internet "someplace". If you use incandescent lights you don't need the resistor, but since the incandescents get hot, you may need to use metal for the black targets around the lights (I used plastic paint can lids). The "visor" over the lights are cut up AquaFina (tm) water bottles, but the most recent pack I got has ribbed sides and would be unsuitable... there are other brands of pop and water bottles that have smooth sides... a metal visor could be cut from a pop/soda can. All were painted black with a rattle can of bar-B-que paint (I happen to have on hand) and it seems to have stuck to the plastic quite well.

It all runs off of a 12V battery pack that has a built-in air pump for inflating automobile tires (slowly!) and has a automotive type 12-V power socket in it. I mounted an On/Off switch in the 4x4 electrical box, but it is not really necessary... at the time I wasn't sure exactly where I was going to obtain the power and wanted to be sure I had a local power switch. I did not fuse it, but probably should have. It draws about 3 Amps when running (the LEDs don't draw much current but the flasher needs to draw that much to work. (If I can find a different flasher that current could be reduced considerably. The 5-Ohm 50-Watt resistor get HOT... a bit too hot. I mounted it in the metal electrical box by drilling and tapping a hole on opposite side about the center of the box. I put a machine screw in each hole to hold the resistor up and away from everything else. The resistor is a hollow ceramic tube so the screws just go into the ends, not that that do anything other than capture the resistor in the middle of the box.








 
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