Multi Color LEDs

There's always the brute force way for PS/2.   Truthfully, I believe that could be accomplished by using some common anode three-wire RED/GREEN LED's and two 330 ohm resistors.  Wire the anode (center lead) to PV and the negative leads to the forward and reverse light circuit.

I haven't looked that closely at the PS/3 yet, I'd have to think about that one.

Red and white would normally be a better choice of colors. Green means extra and there is another section following. White means extra and the only/last train in the extra.

There is some variation between railroads.

I have found common anode LEDs in red/white

Greg

In that case, green would be perfect!  There's always another section following on any train loop that I've seen!

Red/white LED's are fairly rare, and very fragile.  I had a few and several of them inexplicably died when properly installed and protected from excess current and reverse voltage.  Don't know what happened to them.

I looked at the PS/3 board LED outputs, and it shouldn't be an issue to do the same thing with them, however you need common cathode 3-terminal LED's.  The common cathode goes to PCB Ground and the anodes go through a 100 ohm resistor to the front and rear headlight outputs.  The reason for the resistors is to prevent the bi-color LED's from starving the higher operating voltage headlights and not allowing them to function.

Dunno when you last used red/white leds and whose manufacture, but the ones I use have been in service 5 years and no problems. They are not intrinsically fragile. Have used a bunch and no failures (there are a lot of R/G classification LEDs  in one particular LS train's diesels).

Greg

Some TAS/TMCC/EOB from long ago.  Bidirectional/Bipolar LED's  Used the smoke output, programmed different.

I had done some similar wiring for Atlas models wired to track power, the resistor values, (560 pictured), approached 900 to 1000 ohms, if the foggy head remembers correctly. EOB upgrades didn't have a lot of plug-in options for fancy lights. IMO.   Change of color done with reversed polarity, change of direction.

I've used tons of the red/green LED's never had an issue.  I don't know why the red/white ones ended up being so fragile.  I bought them on eBay, probably one reason.

Yeah, most LEDs on ebay are actually factory seconds, from my experience.

I think I had to spend some time tracking them down from the manufacturer, I think the factory is in Finland of all places!

But they won't sell retail... unique-leds.com has them... 3mm and 5mm.

Greg

I found the package, I actually bought them at unique-leds.com, so much for that source.

I've actually had fine luck with the eBay LED's, I haven't seen any issues with them. 

Mike CT posted:

Some TAS/TMCC/EOB from long ago.  Bidirectional/Bipolar LED's  Used the smoke output, programmed different.

Mike, if you program the smoke LED for cab light, AUX1-6, it reverse polarity on direction changes.  Obviously, if you have smoke, that option is not available, then I use my method with 3-lead LED's.

PS-2 and PS-3 would be different method since one operated 6V bulbs for Lights and a separate circuit for Markers.  PS-3 is all LEDs.  MTH does this with flash coding and a secondary PCB to do bi-directional on GG-1s.  G

GGG posted:

PS-2 and PS-3 would be different method since one operated 6V bulbs for Lights and a separate circuit for Markers.  PS-3 is all LEDs.  MTH does this with flash coding and a secondary PCB to do bi-directional on GG-1s.  G

For directional markers on PS/2, I'd just wire to the headlight circuit as I've previously stated.  For PS/3, unless you have the directional marker code native, you can do essentially the same thing.

Here's my comment about PS/2 directional markers.  I don't see any reason this wouldn't solve the directional marker problem without any special code or PCB.

I believe that could be accomplished by using some common anode three-wire RED/GREEN LED's and two 330 ohm resistors.  Wire the anode (center lead) to PV and the negative leads to the forward and reverse light circuit.

As for PS/3, a similar technique would appear to work just using the headlight circuit as well.

For PS/3 you need common cathode 3-terminal LED's.  The common cathode goes to PCB Ground and the anodes go through a 100 ohm resistor to the front and rear headlight outputs.  The reason for the resistors is to prevent the bi-color LED's from starving the higher operating voltage headlights and not allowing them to function.

I'm all ears if you think there's some flaw in this logic.   Previously, you stated that the PS/3 could drive multiple LED's on a single light output.

Well the Rule 17 lighting will make any Led's wired into headlight circuits on a PS3 board act funky as in they'll dim down a bit when parked. 

That's a good point Casey, but they will still work.

You're right as it would work! Could always use some small solid state relays controlled by headlights and power the markers via the P5V grey wires but that'd be some work.