How to power Lionel accessories without a pressure switch

[ed375]

Use the track, metal wheels and axle as your switch.
 
Use special sections, of track, with one outside rail insulated or make your own. Ensure the rail is insulated at both ends of the rail as well as from the metal ties (if any). If possible have 1/8 th inch of insulation at each end of the "switching" section to minimize sparking as the wheels roll across the voltage difference in the outside rail.
It is easy with Gargraves track and fairly easy with tubular track.

Connect one end of your 12Vac, accessory voltage, to the Lionel accessory, then from the accessory to the the insulated outside rail. Connect the other end of your accessory power to the uninsulated outside rail.
When any piece of equipment with metal wheels and axles in on that section of track, it will complete the circuit and activate the accessory.

IMPORTENT: ensure that your accessory power in IN PHASE with the transformer.
With no trains on the track,
set your track voltage to she same as your accessory power.
Measure the voltage from the UNinsulated rail to the center rail (example 12 Volts)
Measure the voltage from the Uninsulated outer rail to the Insulated outside rail (12 Volts)
Measure the voltage from the center rail to the insulated outer rail. If it is in phase it will be Zero Volts or less than one volt. If it is 24 Volts, reverse the wires on the accessory power supply.
This works with the traditional transformers.
If you use modern "transformers", it is your best guess. With a MTH 100 Watt "transformer" and a 12.6 Volt, 5 Amp Radio Shack transformer, for the accessories, phasing is impossible.
I used this setup with tubular track for years. Crossing gate, Switch Tower, and Automatic Gateman (3-tracks)

You may have problems with two or three axle engines, with traction tires, stalling on the section, if the rubber tires are on the uninsulated side of the track. If you have cars with plastic wheels, alternate them with cars with metal wheels.

Ed Hampton, Illinois

[ndbprr]

I think you could do almost anything with an infrared transistor emmiter and receiver using the train to block the signal. It would probably need a dc circuit rather then ac

[San Jose]

I want to avoid using switches activated by pressure to power my Lionel accessories.

I succeeded in doing this using a relay and an insulated rail, but wonder if it is possible to do this in a simpler way, e.g. without a relay. 

I do not want to use track power but constant voltage from a Lionel transformer.         

Please let me know if this can be done.

Nino Yannoni, San Jose