Red Caboose GP-9

The circuit board will likely turn off the headlight when in reverse. I seem to remember that it has some diodes on it.

I would keep the circuit board as it will protect the bulb from over-voltage and spikes generated by the motor. The diodes provides a drop of 0.7 volt each on the voltage fed to the bulb.

I worked a long time ago on such unit and DCCed it entirely. You may want to check the axles and look for split plastic gears, which is a very common issue on these old models. North West Short Line used to sell a replacement set with four axles for less than $50.

Good luck.

Yves

Thank you Yves! I have several NWSL replacement axle gears for the locomotive if needed. I am going to wire GOW bulbs for headlights ala my Weaver units and just tape them to the cab. If the board just controls the lighting I will remove it!

The bulbs with the loco are probably 1.5v and the board probably steps down the voltage to that level.   It is pretty easy to do with diodes.

I don't what GOW bulbs are, but be careful about heat.    The Red Caboose model is styrene with a fairly low melting point.    If the bulbs get too hot, they distort or melt the shell.   

My recommendation is go with LEDs for the lights and just wire a resistor in series with the LED.     LEDs are polarity sensitive, they only light in one direction giving you automatic reverse lighting.     They are also do not get hot.

The second idea is to use the included 1.5V bulbs and circuit board to keep the heat down.

"GOW"..."grain of wheat" bulbs...?  You really are going old school!

I have one of these Geeps; a fine looking and running model...

Mark in Oregon

Are not most Grain or Wheat bulbs 1.5V?   Then you need the circuit board?

The circuit board controls the directional lighting, & gives constant brightness from very low speed. 

Connect the bulbs direct to the pick ups by all means, they'll work for a very brief nano-second, then never again....

I have yet to DCC mine, but will likely replace the bulbs & board with LEDs & resistors when I do - it seems the most straightforward option.