signals

[traindood]

Hello; morin' fellas and gals. snowing hard here in sparta n.j.  should be about 8 to10 inches. any one out there have any advice on a signal system.   so many choices. pricey too.  help. thanx

[willpick]

If you want to have a signal system, then you don't have too many choices. AtlasO system is very good, is cascadable( red signal triggers yelllow in preceding block). i have mostly independant signals(MTH) that only cover 1 block at a time.

There are other companies, but I like the AtlasO system. 

[insfil]

Try looking into Z Stuff.net, signals work off infared detection, easy installation. 

[steve24944]

 I have made some scratch built signals, Green over Red color light and searchlight signals.

Using styrene tube for the mast and the LED housing and sheet styrene for the signal face, I could not find O Scale ladders so I scratch built the ladders with balsa wood and brass wire. The platform at the top of the ladder I found a plastic mesh in a craft store used for needlepoint. For the signal base I used a 1/2 PVC pipe fitting that I place sheet styrene on top and trim to match the PVC, drill a hole to insert the mast. My layout has 1/2 inch celotex over plywood. I cut out a 1/2 inch diameter hole into the celotex, stopping at the plywood to mount the PVC base into.

Radio Shack has an assortment of LED packs.  Green, Yellow, and Red and a 2 color LED, Red + Green that work well for a searchlight signal.  Get an assortment of 150 ohm to 470 1/2 watt resistors. Spend some time playing around with what resistors work best for a given LED and the power supply. You will blow some LEDs before you get it right.  The LEDs use only 1-2 volts DC.  Use a small DC power pack or  a bridge rectifier with an AC power supply. 

For the signal circuit I have a 12 volt Relay that is tripped by the outside third rail. You will need a bridge rectifier to convert the AC to DC to trip the relay.  Radio Shack has relays also. There are 3 sets of contacts, One pair of contacts connected to the 3rd rail closes the relay. The other 2 sets of contacts are DPDT switch, use one to control the LEDs - the other set can be used to control the track power to stop a train at a red signal.  Telephone wire can be bought in 100 ft rolls, with red, green, yellow and black wire inside. Remove the outside insulation and the wire threads nicely inside the PCV tube. Mounting the signal head to the mast with the wires running down the inside of the PVC tube takes some work to get it right. 

Good Luck

[lionelsoni]

This topic got me thinking about how to do LED color-light signals as simply as possible.  This is untried, but here's what I've come up with:

Design an LED circuit for each of the colors, red, yellow, and green.  Connect a ballast resistor to a positive DC supply, then the LED's anode, then connect the LED's cathode (temporarily) to the return of the supply, which will also be the layout common or outside rails.  Use my article in the September, 2008, CTT to see how to adjust the ballast resistor for the brightness you want.  Also put an electrolytic capacitor in parallel with each LED.  This will keep the LED from flickering when the wheels momentarily leave the track and also simulate the slow behavior of real incandescent signals.  The capacitor's size will depend on how much current you're putting through the LED and how slowly you want it to turn on and off.  I would start with 100 microfarads and experiment to find the right value.

Now make control rails the full lengths of the blocks.  Connect each control rail through a 1N914 or 1N4148 diode to the cathode of an LED that you want on when the train is in that block or to the anode of an LED that you want off.  For example, the block just past the signal should turn on the red LED and turn off the yellow and green LEDs.  The block after that should turn on the yellow LED and turn off the green LED.  The block facing the signal could turn on the green LED, so that it would be off if there is no train to see it ("approach lit").  Or you could just connect that LED's cathode to the common through a diode.  Each of these diodes should have its cathode connected to the control rail and its anode connected to the cathode or anode of the appropriate LED.

[traindood]

Hello: wow! all i can say is you are very gifted with that electronic stuff, too bad for me i'm not. i do try however and sooner or later i'll get it. took me over two years to wire my layout the old fashioned way, control panel and all. read books and tortured whoever i could find about electrical stuff. inexperienced but unafraid!   

[traindood]

Hello: just read your post to me, thanx for the reply. it would be easier to teach a caveman about splitting the atom than for me to understand what you just said!! WHEW!    

[lionelsoni]

Here's a sort of schematic that might make it easier to understand:

   ----------------------------------------------
   |            |                 |             |
   |            /                 /             /
   |            \                 \             \
   |            /                 /             /
  +|            |                 |             |
  DC            |-----------      |-------      |
supply       ---|      |   |   ---|      |   ---|
  -|        +|  |green |   |  +|  |yellow|  +|  | red
   |        === V LED  |   |  === V LED  |  === V LED
   |         |  |      |   |   |  |      |   |  |
   |         ---|      |   |   ---|      |   ---|
   |            |      |   |      |      |      |
   |        --> V      V   V      V      V      V
layout  1N4148  |      |   |      |      |      |
common  diodes  |      |   |      |      |      |
                |      |   --------      |      |
       control rail A  |       |         |      |
      or layout common |  control rail C |      |
                       |                 |      |
                       |-------------------------
                       |
                control rail B

There are three consecutive blocks, A, B, and C.  The signal is at the boundary between blocks A and B, facing block A.

[traindood]

Hello Bob:   thanks for reply, one tiny problem however; when God was giving out brains i thought He said trains; and i said; Dear God, i would be happy if i could have a small one. He granted my wish and you know the rest!!  

[fifedog]

If lionelsoni can help a , he can help a caveman...

http://cs.trains.com/TRCCS/forums/t/162513.aspx?PageIndex=3

That's actually Bob up on the MofW car.

[traindood]

Hey fifedog; will get back to present time soon as i finish skinning mammoth i stoned early this mornin'. can't beat those mammoth steaks with a tall brewski!!       YUM!   later.