Wiring problem on ho train


New Member
Feb 21, 2023
I would like advice on how to wire 4 1.8 volt bi-color led's to a tortoise switch machine. I have been able to make the 4 leds work properly, however the switch doesnt throw. My power source is a 12 volt DC transformer. Please note that I am a novice and dont understand electrical jargon. Thanks JimboP


Staff member
Apr 6, 2013
This is one of the simplest online tools I could find. You use the known values you have, and it will create the circuit for you in picture form. It works welll. Their is a learning curve, but you should get much help with this. If you made 4 circuits in paarallel, voltage in parallel does not change, that could work for you. :)

  • Like
Reactions: OldMiner

Bill Nelson

Well-Known Member
Dec 15, 2008
Clarksville Tn
one big question, how far is the top of the tortoise from the trow bar tortoise from the throw bar? this design, with the materials provided works best with 1/2 inch plywood , and cork roadbed, so the throw bar is less than an inch from the top of the tortoise. if , for instance, you are using 3/4 inch plywood , with inch thick homasote or foam, (I hate track on foam). the piano wire provided is to flexible to make the switch throw correctly,

I'm a fan of ground throws, and haven't used tortoises, so I'm not familiar with the wiring, although I have used blue point manual controls, that have a similar action, and at times have had to replace the provided music wire with stouter music wire to get the switch to throw. check your wiring on a tortoise that isn't installed, and see if it throws