train detectors

[deadhead 49]

I have a double main line covered over  I beleive that I read in one of the model r/r mags. that someone made one from a radio shack senor (on top)and a led light(on bottom) I would really thank someone for helping me on this project I hope I'm in the right forum thanks deadhead49

[ndbprr]

There are several ways to detect trains.

1. A CdS cell (available at Radio Shack) that lets you know when light is or is not present.  As long as there is sufficient room light they work pretty well.

2. A magnetic reed switch placed in the ties with a magnet on the train to activate.  Ok but not the best.

3. An infrared transistor circuit that one piece emits infrared light and the other collects it.  the train can break the beam to signal occupation.

4. A torroid coil around the power feed that lets you know current is being passed hence an engine.

there are probably several others but all will need additional electronic input to work signals.  if all you want is an LED on your panel saying a track is occupied that is a much easier circuit.  What you want to do with the signal is important to provide the right circuit.

[BlueHillsCPR]

Here are a few links to different detector circuits.

http://home.cogeco.ca/~rpaisley4/IrProximity.html

http://home.cogeco.ca/~rpaisley4/PhotoDetectors.html

http://home.cogeco.ca/~rpaisley4/ATDetIR.html

http://home.cogeco.ca/~rpaisley4/ATLaser.html

I understand that you have a double track mainline that is hidden.  What is the detector circuit going to do for you?  Block signaling, control panel feedback, switching, etc.  Are you wanting detectors on both tracks?

I'm no Electronics engineer but there are others on the forum that know alot more than I do, they will probably help you out.  I'll certainly do whatever I can to help you out. 

 

[larak]

Here are a few links to different detector circuits.

http://home.cogeco.ca/~rpaisley4/IrProximity.html

http://home.cogeco.ca/~rpaisley4/PhotoDetectors.html

http://home.cogeco.ca/~rpaisley4/ATDetIR.html

http://home.cogeco.ca/~rpaisley4/ATLaser.html

If you are comfortable with building electronics this is good stuff. You can even purchase some of his PC boards. (making the boards is the hard part).

Karl