Beacon Light wiring for DCC


Hello, I am beginning my first DCC wiring in an engine. It seems pretty straight forward, especially if I had a DCC system that operates additional functions beyond lighting, such as any of the Digitrax systems. But, I have an old MRC Command 2000 system that works perfectly fine, but does not support additional functions beyond directional lighting. Well, in my first project ever, I have decided to add a Beacon light that is a flashing yellow LED. I would like this light to be on any time the engine is in use, or if need be, have it be on any time it is on the track with power. Using the Digitrax decoder, it has a fourth function wire where this LED would normally be connected, however with my system, this fourth function is not supported. So, I am wondering how I should wire this beacon LED so that it functions with my out of date DCC system, or do I really need to spend around $500 for a new system? If I purchase a new DCC system it will be a Digitrax system with a hand held controller that is not tethered to the control box. Radio or infra system, as If I have to put out hundreds of dollars I may as well give myself some freedom of movement. Any suggestions or help, so I don't have to buy a new DCC system would be fantastic! Thank you.
 
I was at my local hobby shop asking about a dedicated beacon for engines. They showed me a small pc board that fits under the shell that does exactly what you are looking for. I wish I had the manufacturers name but I am sure if you do a search online, you will find something similiar.
 
Thank you for the suggestion. However this project is a tiny 44 ton engine with no room for anything beyond the N scale decoder and Beacon in the cab section of the engine. On another forum it was suggested to while using the proper resister, to wire directly to the power pick up wires and the beacon will be on at all times when there is power to the track. I am thinking that this is what I need to try with such a limited amount of space. Thanks though for the suggestion.
 
Thank you for the suggestion. However this project is a tiny 44 ton engine with no room for anything beyond the N scale decoder and Beacon in the cab section of the engine. On another forum it was suggested to while using the proper resister, to wire directly to the power pick up wires and the beacon will be on at all times when there is power to the track. I am thinking that this is what I need to try with such a limited amount of space. Thanks though for the suggestion.

If you don't care if it's on all the time, a LED to the pick-ups as suggested to you would be the best option. I have used LED's with resistors to do what it seems you want.
 
I have discussed this with a friend and fellow model railroad club member. He told me that I should just wire the beacon light properly and that we can, at the club computer, program my fourth function to remain on all the time or come on with the function F0 for the directional lighting. So either way it is programmed, the light will come. So, since I will eventually upgrade my system, I will wire the beacon to the fourth function properly and program it at our club layout so it will be on all the time.

I would like to thank everyone for their helpful suggestions.
 
If you don't care if it's on all the time, a LED to the pick-ups as suggested to you would be the best option. I have used LED's with resistors to do what it seems you want.

Unlike a light bulb, wiring an LED directly to power pick-ups on a DCC layout, even with resistors in place, will not work, and may fry the LED in very short order. DCC power is alternating in nature, and as such is not suitable for LEDs, which require DC power flowing in only one direction to work. If you wanted to wire LEDs directly to track pick-ups on a DCC layout, you would need to add in a bridge rectifier in line to "straighten out" the polarity. These devices are pretty small and can easily be wired up in line with the required resistor. You can get these rectifiers for very cheap on eBay (<$5 for 10, shipped).

Of course, this still won't give you the flash. That said, there are "blinking" LEDs out there. With these, the flashing circuit is already integrated into the LED itself. The only caveats with these is that they may come in limited colors and you will not be able to vary the rate of the flash. If you can't find one in the color you need, you could always try to find a clear blinking one and simply paint the LED lens in the desired color. This way, you get the rudimentary flash without having to add in yet another circuit under the hood.

Finally, make sure you use a high enough resistor value. For the beacon, you probably won't want the LED flashing at its brightest. Try a few different resistor values, starting at 1k, and go up from there until you get to the brightness you like. Hope this helps!
 
you would be better off wiring it directly to the decoder, or a board where you can turn it off/on. if the engine is sitting on a siding, or sitting idle in a yard, that beacon can get pretty annoying..
 
Just food for thought, you don't need to spend $500 for a DCC system. Digitrax and MRC both make reasonably priced complete systems, and they are significantly less than half the $500.
 



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