LGB 51950 colour light signal

[Neil Robinson]

Does anyone know how this signal actually causes the lights to flip from red to green and back?
Any ideas?

I'm almost certain that there is a magnet in the "slider" and a changeover reed switch in the base of the signal.
I suggest you wave a powerful magnet around the base of the signal, if that doesn't change the aspect the reed switch is probably stuck and needs replacing.

 

[dutchelm]

The base of the signal has a 3 terminal reed switch inside operated by a magnet on the slider.

http://www.modell-land.de/platine-lichtsignal-50950e016-p-3785.html < Link To http://www.modell-land.de...-50950e016-p-3785.html

 

[hornbeam]

interesting, always wondered too. So looks like they could be converted to standard operation by switch without the motor then.