I have been told to use ATLAS signals for my newest Interburban line. But what I read of Atlas needs insulated rails to detect the train. Can you do that in 2Rail DC???
What do YOU use?
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Atlas two rail signals do need a detector unit for each signal on a two rail line.
My manual says I have to insulate a 10 inch rail on one side only with a plastic joiner. This creates a block. When the engine reaches the next 10 inch section with it's single insulated rail, the signal that sees it will turn when the engine leaves. Now if you had a Caboose or something still in the previous block and the signals are tied together, they should behave properly.
Three rail signals from Atlas will not need this detector unit and is somewhat simpler.
You have a choice of timed signals, ABS or manual use.
Other signals such as MTH apparently rely on a IR detector and I don't know how to tie them into the Block system I prefer to use to protect the train in front.
The Atlas detectors are current sensing using diodes. This should work with DC, 2-rail AC, or TMCC, but will interfere with DCC or DCS. Dallee and NCE make detectors that you thread the hot wire through which senses the current without affecting the command signal coming down the track power feeds.
There's a technique that the Free-Mo groups are using called the "modular signal system" (MSS) which uses a combination of optical and current sensing. The trick is that they use optical (infrared or photocell) at the ends to initially trigger the block as occupied, with a current sensor in the block to detect the locomotive, so as the train clears the first optical, the current sensor is detecting the locomotive/passenger cars. As the locomotive leaves the block, the other optical sensor detects the rest of the train, keeping the block in an "occupied" state until the last car clears. It's bi-directional. Pretty clever, these humans.
Are you saying they are simply plugging ONE signal into two separate Optical or IR Detector no matter how far apart these things are?
