Installing alternating ditch lights

Looks like a standard LED flasher consisting of 2 Transistors/2 Capacitors/4 Resistors. The speed that the LEDs blink is easily adjustable. I did a quick google search for a shematic http://wild-bohemian.com/electronics/flasher.html. In the first schematic on this page, you can change the blink speed by changing the 100K ohm resistors or the capacitors or both (simple RC time constant).

As for a DC source the Williams diesel I have has a bridge rectifier on the control board (forward/reverse board).

Actually, I believe you change the 100K resistor values, the 470 ohm resistors are the current limiting for the LEDs.

John is correct. I made a mistake in my post.

If you're saying your diesel has electronic bell/whistle, then it has a regulated DC supply.  I'd think that DC supply could be tapped to drive your ditch light circuit.

I got Ditch Lights from Evans. You can get Track Power or Battery power. Really made a difference to my Williams NS Executive train.  It is called a Wig Wag has 4 leds  ( you can get up to 6 leds I belive)   when you order it just let them know you plan to use as Ditch lights and it comes wit just 2 leds. .  I know you can make your own for less but I prefer to buy a made up unit .  

This looks perfect- I would actually mount the button on top of the engine, so we can change things up from flash to steady burn.

http://www.modeltrainsoftware.com/wigwagcircuit.html

I think I Will contact them this week & talk with them. Thanks for the tip!

Just let them know track power and you only need 2 LEDs. I hid my buttom on the

rear of my F-3 in the window. I use a lot of LEDs from them. You also might want to change the head light at the same tome.

There's a circuit like that on the ERR site as well.

Anybody do a ditch light circuit for TMCC? I did one about 10 years ago and may still have the circuit in my archives.

The complex part is knowing when to blink the lights!  Working on a solution with others, maybe we'll have a solution soon...

??? I thought ditch lights blink when the horn is blown.

Right Gary, and electronically, how do you know when that is? 

Hint: You have to monitor and decode the serial communications to the RailSounds board.

Yup! I seem to recall Atlas bought my circuit and used it in their diesels.

What circuit would that be?

The ditch light circuit. I also added it to some of my Lionel TMCC equipped diesels.

Do you have any details?

Here ya go.

Hmm...  Without any software in it, the PIC is kinda' useless.  

I'll send you a PIC if you want to build one.

It that a thru-hole or SMT device?  I could easily hand-wire a DIP package.

For what its worth, I spoke to Evens today. For two LED's in an alternating pattern runs on ac or dc $16.99.

http://www.modeltrainsoftware....ernator-circuit.html

ready to easily install for those of use that don't have an interest in building one.

I think you're really missing the point, for command operation you have no way of triggering the Evans lights, you have to decode the serial data stream.  That's what the PIC in Pete's design is doing.

Real easy to install, not so easy to get functioning correctly.

It that a thru-hole or SMT device?  I could easily hand-wire a DIP package.

To GRJ:

I programmed a couple of PICs ( 8 pin DIP ) but I have no way to test them. The Atlas boards that I installed in my engines use an SMT. If you are interested email me your address and I'll send you one.

It's on it's way.

Atlas has boards with this part already programmed?

Looks like a low on pin 3 will tell the lights to flash, I can just pop this into a proto board, apply power and see if it'll drive the ditch light LED's.  Should be easy to see if it works before actually wiring up a board.

I presume the input to pin 3 is de-bounced, as I suspect the output of that optocoupler pulses with the headlight voltage? 

Do you have the code for this function?

This looks interesting

www.ebay.com/itm/370798217106?...e=STRK%3AMEBIDX%3AIT

Dale H

Interesting for what?

flash alternating LEDs in a small package cheap. No 555s or capacitors

Dale H

Why is pin 13 of the R2LC (Front Lights) used?  Can the code for the pic get posted?  G

The ditch lights only flash when you have the headlight on, that's why the headlight output is tied in.

How does IC2 orchestrate that how it is wired?  G

IC2 is an opto-isolator, it's just being sensed by the input on the PIC chip when the headlight from the R2LC is on.  R4 is the PUP, the opto is low active when the headlight is on.

If you noticed that prototype ditch lights have a very slow turn off time. The light is barely off when it is turned back on. I simulated this in my design. Most flasher circuits don't do this and don't look prototypical.

I haven't seen your circuit work yet Pete.

Which Williams Diesel is going to get the ditch lights?

The rest of the lights on the Williams Diesel can be improved with Evans 1.8mm Warm White or cool white LEDs.

Andrew

I did not install any ditch lights in the WbB GP38. I installed 4 warm LEDs, two overhead and two in the nose where the plastic imitation lights were. I also installed 4 in the rear. All kinds of light, and thats what we needed for our community layout. 

I was shocked of the lack of room in the WbB around the flywheels. There is no room between the flywheel and the roof of the diesel. I thought I could skinny some micro wires overtop of the fly...and I was wrong. 

Still a fun project that was pretty easy. Actually looking forward to the next LED upgrade, as I learned a lot and the next should be easier.

I've had a couple of diesels that I actually had to cut away a bit of the shell to keep the flywheel from rubbing stock from the factory.

Do you have the TAS documentation for that unit?  I'd like to see what they did to sense the horn to trigger those.  I believe I have a way, but I haven't gone that far yet.  I'd probably base mine on a prototype that ERR did some time back that uses serial data to trigger the ditch lights.  I was hoping they'd release that unit as it solves the problem, but I don't know where that is at this point.

These lights don't flash but they are part of an early Atlas Dash 8 that had a TAS SAW Gen2 board.  Unfortunately the SAW Gen2's didn't do well, this unit has an EOB board. The lights, LED's, shown are attached to track power with series resistors.