Building custom Train Signaling Board

[SlavaK815]

Hello,

It took me lots of time to build bench work/roadbed/track/wiring so in the mean time I was thinking about how to make signals work on my future railroad. Eventually I’ve decided to build my own circuit board that will take various sensors inputs and provide outputs for LED signals. It was good exercise and finally I've got board I wanted for my layout.

Here is what I have so far –

1. 1. Board supports 12 sensors inputs. Each sensor input can be connected to one of this kind of sensors–

1. Photo reflective sensor based on OPB733TR (to sense when train leaves of travels to/on main) that will be installed under track
2. Current Detection sensor to work with NCE BD20 (to sense when station/yard track is occupied)
3. Track voltage sensor connected to turnout frog to sense turnout position

• Each sensor will have 0.3 seconds OFF->ON delay to avoid false positive and 0.5..60 ON->OFF seconds delay (adjustable per sensor input with Potentiometer) to extend sensor’s ON state, useful for current and photo sensors.
• Board provides 10 logical outputs. With Simple programmable logic device ATF22LV10CQZ each out of 10 outputs will be a logical function of 12 inputs. Each board will have its own programmed logical function to convert sensors input to signal output.
• In addition to 10 output’s – first 8 outputs will also have extra 8 inverted outputs and two always-on outputs.

The board is 6x4 inches and will be installed in areas with multiple switched where signaling in desired. I've built 6 boards and installed 3 so far on my layout

I've published 15 min demo video on youtube. I have few extra PCBs and can provide build instructions if you are interested.

https://www.youtube.com/watch?v=4kIIFt95etc

Slava

[BroadwayLion]

LION is way ahead of you, but him has no use for little circuit boards. HERE is the "circuit board" for the Route of the Broadway LION. I handles 42 blocks (station edges). It includes train detection, signal operation, and train automation. Detectors are reed switches embedded in the tracks, magnets are placed on the underside of the train.

 

This photo was taken after the cables to the layout were installed but  before the relays were connected. Five conductors connect this panel to the station edge.

1) Detector from track
2) Green Signal

3) Yellow Signal

4) Red Signal

5) Track Relay to allow train to depart station

The cables as shown at the station edge.

 

I built a representation of a GRS interlocking machine, and put a modelboard above it which shows train locations.

 

 

Good luck with your implimentation. With big furry paws, little circuit boards are a problem.

 

ROAR

[SlavaK815]

 

Thanks for sharing.

 

And I thought I had too many wires .

 

Two of the main design goals for me were to have a board that

 

1. can sense various type of sensors and be able to sense switch position without requiring any type of switch motor, so switch could be thrown by hand or by any type of switch motor.

2. I can program and install in various places on my layout to get desired signaling. For my 10x16 ft layout I’d need 6 boards to drive about 40 signal heads.

 

Picture below is an example of one of the boards installed for one side of classifying yard that drives 9 signal heads based on position of 8 switches and 1 photo sensor.

 

I can also connect reed switch as a sensor, I preferred photo sensor as it does not require magnet and also works on rolling stock. For long track sections I use current detectors.

 

 Slava

 

 

[hon30critter]

Slava:

That's pretty neat! Well done.

I'm planning on using IR detectors to detect the presence of trains where needed but my signals will be controlled by the position of the tortoise switch machines. It won't be prototypical at all. I just want to see which way the turnouts are thrown.

I hope I can keep my wiring as organized as you have, and I really like the idea of being able to flip the layout surface up to work on the underside. Would you be willing to explain how you approached your layout construction?

Thanks

Dave

[SlavaK815]

Dave:

>I just want to see which way the turnouts are thrown.

yes, I wanted to do the same for some places on my layout, yard would be one of them. But instead of requiring any particual switch morot my signaling board detects switch position by checking voltage on one of the moving rails of the turnout. The board is programmable and can accomodate various scenarios and sensor types. Here is a demo of my Yard exit -

https://www.youtube.com/watch?v=cDfP5rN1lWM

>Would you be willing to explain how you approached your layout construction?

My layout is 10x16 ft HO, it somewhat modular. I can take it apart if I move but this this not something that can be done esily. It has 4 tables and 3 cross sections. The frame is build of 2"x4" lumber with 1/2" playwood on top with cork as roadbed. Woordorking was done in garage and pieses were put together in bonus room.

I think one of the unique featues of this layout (besides my signaling system :-) ) is how I built cork roadbed. Instead of bending cork strips I used 2'x4'x1/4" sheets of cork and carved exact pieces I needed. Then I've gues it and painted plywood and cork. In the middle of my layout I have two levels with staging tracks in the bottom and yard on top.

I've designed my layout using AnyRail software and then printed it with 1:1 scale and transfered to my modules.

I've shared some pictures of my layout in various stages - feel free to ask any questions.

https://goo.gl/photos/oR7vQhsmExi8T4hFA

 

Thanks,

Slava

 

 

[BroadwayLion]

SlavaK815

Picture below is an example of one of the boards installed for one side of classifying yard that drives 9 signal heads based on position of 8 switches and 1 photo sensor. I can also connect reed switch as a sensor, I preferred photo sensor as it does not require magnet and also works on rolling stock. For long track sections I use current detectors.

 

LION seas no picture. : (

 

ROAR

[JoeinPA]

I saw it by clicking on the little square under his signature.

Joe

[SlavaK815]

I am new to this forum, is there a way to edit submitted posts to fix typos, links etc?

[ricktrains4824]

The bottom of the post you made should have an "edit" button, right near where the "reply" option is.

[SlavaK815]

Thanks, I only see two buttons "Reply" and "Quick Reply". Perhaps that is becase I am new here and I am on "trial period" ?

• Slava

[hon30critter]

Slava!

I'm impressed with your signal system and the quality of your construction!

Very well done.

Dave

[SlavaK815]

I’ve now installed all the signals on my layout - 26 dwarf signals, 16 tall 2 aspect signals and 2 signal bridges that have 4 of 3 aspect heads. The signals operate according to switch positions and photo or occupancy sensors and connected to 6 of my custom designed signaling boards. Photo and occupancy sensors are set to 25-30 seconds delay and yellow is set to 8-10 seconds delay before green.

http://www.youtube.com/watch?v=RKKzKMxEVMo