http://i220.photobucket.com/albums/dd51/Hwolf_photos/Best%20of%20Wolfcreek/IMG_3470.jpg
I want to put IR sensors in the two tunnels shown above.
The exit to the tunnel is behind the building on the right side
1. Can they be connected to a THREE light signal?
2. Can you make your own IR sensors or does it not pay?
3. If you can explain how, or put me to a good source for the equipment.
The go to place for simple circuits like that is Rob Paisley's site: http://home.cogeco.ca/~rpaisley4/CircuitIndex.html
Not sure how you'd get 3 color signals out of that, assuming you want red to show if there's a train already in the tunnel. If you put a third sensor in the middle of the tunnel you could have the signal red if the first sensor is blocked, and go to yellow when the middle one finally clears - but this would result in two trains approaching from the opposite sides both getting a yellow - with a collision in the middle. Simple logic would be the two sensors, one at each end, if both sensors are not blocked, green light, if either one or both is blocked, red light. A middle sensor might help if you run trains shorter then the tunnle length, otherwise a short train int he middle of the tunnel will display green lights to both sides.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
The more I thought about it, I realized the three lights must go. How about the other questions?
Why not look at South Bend Signal? The sell and IR based block control system and it includes the signals:
http://www.sbsignal.com/
For about $57 you can get a block of IR detection and a pair of signals....
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
It looks like a nice system. Have you ever used these people?
Have you ever tryed to make your own IR sensor? If I buy this for one tunnel I will still have two more signals I can use.
I have something like 8 blocks of their signaling. When either IR sensor is covered, the signal will drop. After the sensor is uncovered, it will 'hold' the red signal for something like 30 seconds. So, if you are planning on 'parking' a train in the tunnel, make sure the one of the IR sensors are covered. You can buy just the detector and the IR sensors if you want to use your signals Check with them if your signals are compatible.