Homemade block detection for signals

[Marc_Magnus]

Since my mainline is nearly complete and running, I need signals but also block detector occupancy for actuating signals.

Severals block detector are offered but are quiet expensive especialy if you need some.

Did anyone have a plan of a homemade block  Thanks a lot.

Marc

[cacole]

Here's a good site to start off with --

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

 

[Texas Zepher]

Here is another place to try. See detector #5 about 1/2 way through. http://www.tslrr.com/detector.htm