Exciting Topic

Hi Ian,

Detection / signaling systems always start a lively discussion.  Here we go....

If you operate in darkness, you'll have to go with current detectors and resistors on all your unpowered rolling stock, or use reflective IR detectors under the roadbed.  If you don't, you can use optical detectors.  They're inexpensive, but you need a lot of sensors.  There are a lot of articles on the web showing different methods of detection.  Do some research and see what looks good for your layout.

Once you've detected a train, you'll need some type of hardware/software to drive the signals around your layout.  Again, get to the web and do some research so you know what it's going to cost you in time and money.  JMRI, Bruce Chubb and others all work well. 

To give you some idea of

To give you some idea of costs and system;

one control plant: meaning, one turnout or crossover. 

Digitrax SE8C control Board - Controls 32/64 signal heads and 8 turnouts.  approx $120

Digitrax BDL168 Detection Board - Block detection for 16 blocks. (you will need at least 3 blocks per CP to do it right) Approx $120

BLMA Signals Vary in price and styles. $30 - $100+ To complete one plant you will need at least 2 double headed signals and one single head.

   As an example.

Locobuffer. This is the interface with the railroad and a computer approx $70

As Bruce said. Some form of current draw has to be placed on each piece of un-powered rolling stock. this is fairly in-expensive but is time consuming to do. Ask me how I know!!

Computer Program. This makes running the signals a whole lot easier. JMRI is free. Railroad &Co starts at $350+ up to about $600 Personally I use RR&Co as it does what I want and is very easy to use, but that is a whole different thread.

So in a simple answer. To do it right a lot and takes time and knowledge. 

As an alternative. Atlas offers a very simplistic signal system. It is proprietary and I don't think it will work with other systems.

I think your first thing you should consider is what level do I want to go to here? Are you looking for signals as scenery or as an operation tool. One thing I have not covered here are the types of signal systems. Are you looking for ABS, APB or CTC. 

signals Help

hey thanks for the info... All i want it to do is as the train goes by the signals go red and at a time back to green

Ian

Arduino / Picaxe / 555 Timer

Hey Ian,

Your difficulty and price went way, way down.  All you need is an IR reflective sensor mounted below the roadbed(Refer to article in Model Railroader magazine) triggering a cascade timer(dual 555).  There are several circuits on the web and they're not difficult to build.

I installed that type of system on my Ntrak module.  Since we never operate shows in the dark, I could use cheap CDS photo resistors.  The signal goes red while the train covers the sensor, then waits for N seconds, changes to yellow, waits N seconds and changes back to green.  Since Ntrak is a large loop, I could count the seconds it took for the train to make one loop and divide that by 3 to get "N seconds".  I used Picaxe microprocessors for the detection and timing.