GP9 Lighting

Generally, all number boards would be lit regardless of direction, and the headlight in the direction of travel lit as well.  Real locomotives have the option to have one or both headlights on, and either bright or dim depending on rules and situation. The headlights would never be red, but the class/marker lights (top corners of the hood ends) can be lit up red, green or white.  Red is a marker light for the rear, green indicated a second section following and white is an extra train movement.

@mlavender480,

Thanks, your info is much appreciated and I will go with what you said.  But, for the marker lights in the forward direction, from other stuff I've read here, they would most typically be green, correct?  I'm just looking for the most typical configuration.

@texgeekboy posted:

@mlavender480,

Thanks, your info is much appreciated and I will go with what you said.  But, for the marker lights in the forward direction, from other stuff I've read here, they would most typically be green, correct?

No. The front class lights (they are not 'marker lights' as on the rear of a caboose or passenger car), would "normally" be white. As info: 1) "white" class lights indicate an "extra train", 2) "green" class lights indicate a "second section following", 3) "red" class lights would only be displayed on the rear of a light locomotive movement, or as on a rear of train helper unit with the "red" displayed to the rear.

I'm just looking for the most typical configuration.

What I just provided would be the most typical prototype configuration.

Of course, on a typical model train layout, it'll be going in a loop, so it's always a second section, so I pick green.

I did see someone on an OGR thread add some of these lights to an steam locomotive, and he chose green.  Actually, he installed little green plastic lenses.

The other question about GP9s I have isn't about lighting.  When my train starts up, the small end is in front.  I saw a post on another thread where the guy was adamant that the long end in front is the way it was run on railroads.  For freight service I think the small end should be in front, that way the noise and smoke is behind the engineers.  But for passenger service, perhaps the big end should be in front to allow the noise and smoke to dissipate as much as possible before it gets to the passengers.  This is said with my very limited experience riding on actual trains.  Other than subways in NYC and London, I've only ridden a train once, from Krakow to Warsaw, and I believe it was electric.

Different railroads ran the GP9 either long hood forward or short hood forward.  Just go find pictures of the prototype of your road name and look to see which way they ran.

@gunrunnerjohn,

Thanks for the suggestion re old time pics. The Milwaukee Road GP9s were run with the small end forward. That’s good because I just spent a lot of time cutting 2 engineers in half and gluing them to the tiny area near the windows in the proper forward facing direction.

@gunrunnerjohn,

After I started this project I realized providing separate bulbs for the board lights to be always lit would be pointless since the light bleed through on the plastic assembly (headlights, boards, marker lights) is so great I wouldn't be able to have only the board lights come on (without expending more effort than I was willing to do).  Oh well.  The only enhancement (besides LEDs) that I would have would be to always have lights on in the cab.

I proceeded with installing 5mm warm white LEDs for the 2 headlight lenses in the front and back.  After gluing them in place, I snipped the hot/common wires going to the factory incandescent bulbs, hooked them to the LED leads, and got nothing.  I used a 430 ohm resistor and made sure all the polarities were correct.  In the last month I must have done over 20 LEDs (not counting strips), and never had a problem.

The first picture shows the factory bulb reconnected to the circuit board, so the circuit board isn't fried.  The second picture shows the LED headlight assembly connected to the circuit board, nada.  The third picture shows the LED headlight assembly connected directly to the transformer.

There are 3 separate hot wires from the circuit board to the lights (one front, one rear, one flashing).  There is only one common wire for all 3 lights.

The factory incandescent reminds me of bulbs in a Christmas tree with a contact on either side of the holder, so it isn't like a typical bulb.  Is that the issue?

I'm stuck.  I didn't expect this.  Any ideas?

I'm still plugging away at this, and made some new discoveries.  Unfortunately I have no idea what they mean;

1. In the first picture below, I have the LED assembly connected to the circuit board, and also I have the factory incandescent bulb connected to the same wires.  They LEDs now light up.  Huh?

2.The bottom picture is the inside of the factory bulb holder.  If I take the bulb out, the LEDs don't light up.  This reminds me of the holders for simple strings of Christmas lights.

I've tried a lot of other permutations, but this is the only positive result.  I'd simply connect the LEDs straight to the power & common coming off the rails, rather than the circuit board, but that way I wouldn't be able to have directional lighting.

The control board for the lights need to see a load to turn on. LED's don't have a load. That is why your LED's don't light. Either keep one regular light for the markers or add a resistor to the circuit for a load.

I have a 430 ohm resistor. Does it need to be more?

@texgeekboy posted:

I have a 430 ohm resistor. Does it need to be more?

Maybe. Try a 1K ohm and see what happens.

Don't use a resistor, a .01uf 50V ceramic cap will provide the triac triggering load but won't consume any power or get warm.  FWIW, the ERR boards all include the .01uf cap so that LED's can be used with those.  For existing TMCC stuff, I add the .01uf caps.

Thanks @gunrunnerjohn.  I guess I still need the resistor for the LEDs, or maybe not if that power is DC by the time it reaches there?  Of course, I may sound stupid but I figure I might as well shoot for the stars.

The series resistor to limit current is still needed, the .01uf cap I mention is to trigger the triac and it's connected right across the lighting outputs to ground.

Since the LEDs worked when I connected the factory incandescent, my first connection attempt for the capacitor would have been exactly where that was connected, so I would have had a lucky guess.

The capacitors are being delivered tomorrow, but I'll have to put that aside for a bit.  I gotta go work a swim meet, my other 'hobby'.

The capacitors worked great, thanks @gunrunnerjohn.  I thought I was on the home stretch and was attempting to tap into the power feeds for the always on blinking light on top (to power lights for the cab).  I found out the blinking isn't because of the light bulb, but it comes from the circuit board to the power for that light.  I will have to tap into the raw track power to power the cab lights.  I don't want the engineers to be in the dark.

Another question came up, the picture of which is attached.  This strip of aluminum (?) is loosely connected to a plastic protrusion from the roof of the engine, and it connects to the circuit board.  Nothing is connected to it, and I could find no metal to which it connects.  Any idea why it's there.  The only thing I could see that it did was to block the blinking light from leaking through to the cab.  That's fine, but why connect it to the circuit board?  I've kinda run the engine and don't see that anything has changed.

As I'm writing this I thought, is this some type of antenna?  It says it is Command Control equipped, although I can't use that right now.

Excellent guess.  That is indeed your TMCC antenna, and you do not need it for conventional operation, only for command control.

Mike

It's the antenna, but don't forget you took it out if you later want to run in command mode.