Working block signals without rail gaps or resistor wheel sets

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johnp

New Member
A new circuit enables simpler installation of operating block signals. Traditionally, block signaling required insulated rail joints, resistor wheel sets and current sensing detectors to make the signals work. The Azatrax TS2 is a new product that uses two infrared (IR) sensors to detect trains passing a block boundary, and operates two block signals at that boundary (one signal for each direction).

The TS2 includes features with builders of traveling modular layouts in mind. Multiple TS2 circuits can be linked together with a simple 2-wire connection to enable signals on adjacent modules to be coordinated. If the next module does not have a TS2 circuit, your module's TS2 will automatically revert to a timed mode. In timed mode, the TS2 measures the speed of a passing train and then changes the signal aspects to simulate the train going through successive blocks down the track.

The infrared sensors are pulsed to eliminate effects of room lighting. No adjustments are needed when the room lighting changes or if you move to a different location. The IR detectors can work even in complete darkness.

The TS2 automatically senses whether your LED signals are common anode or common cathode and adapts accordingly. Current limiting resistors are built in. Signals with incandescent bulbs will not work with the TS2.

An on-board jumper lets you select 3-aspect/2-block or 4-aspect/3-block operation for most types of LED signals. It also has an interlocking function allowing you to set a stop signal for draw bridges, diamond crossings, etc.

The TS2 is available directly from Azatrax,

Cost is $39.00 USD each, or $99.00 USD for a 3-pack, plus shipping/handling.
John P.
 
A new circuit enables simpler installation of operating block signals. Traditionally, block signaling required insulated rail joints, resistor wheel sets and current sensing detectors to make the signals work. The Azatrax TS2 is a new product that uses two infrared (IR) sensors to detect trains passing a block boundary, and operates two block signals at that boundary (one signal for each direction).
So what happens in the all to common case where the train breaks in the middle of the block and a car and caboose are "left behind". Do the infrared sensors measure the length of the train going in and compare it to the length coming out?
 
johnP:

Circuitron offers a Signal Animator which mounts under the layout and a small photo cell between the rails detects a train cross over the photo cell. The Animator will operate a Tomar three light signal. First the red signal will operate then turn to yellow and then back to green. Easy to install and trouble free.

Thanks.

Greg
 


Poking around the internet I have found this is a renewed version of one that was marketed a few years ago and made in China. It's great for a demo set up with trains just running a short loop, but operations, standing trains, short trains, broken trains etc. it doesn't work well.
 
So what happens in the all to common case where the train breaks in the middle of the block and a car and caboose are "left behind". Do the infrared sensors measure the length of the train going in and compare it to the length coming out?

Good question. The sensors do not measure the length of a train, they only know when a train enters or leaves a block at either of two ends. If a train uncouples, the sensors will not be aware of this and will show the block as clear when the head end of the train exits the block.

This is a limitation of this simplified system. Most model railroad track is visible to the operators and block signals are a cosmetic feature. Where you do have hidden track you can incorporate supplemental train detection, whether infrared, current detection or whatever, and as long as it can switch a signal line to 'ground' then it can be connected to the TS2 circuit and the block signals will correctly show the block as occupied.

See the 'Interlocking functions' paragraph near the bottom of the TS2 web page, www.azatrax.com/TS2

John P.
 




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