Signals, how to wire them?

[zephyr1934]

What about using a two color LED and a resistor? It is pretty simple. I did that with these a while back. If you get 3mm LEDs they fit nicely in the hole in the 2x2 dishes.

[Locomotive Annie]

Wow, - that's a really cool setup Zephyr..

[zephyr1934]

Thanks L.Annie. My current signals are working semaphores... I need to get photos of those posted one of these days.

Meanwhile, I forgot to mention that the LEDs will light one color with positive voltage and the other color with negative voltage applied to the terminals.

[Locomotive Annie]

Those LEDs sound to be very useful for railway purposes Zephyr. I would seriously love to see photos of your semaphore signals though as my own line will be mainly using them.

[bricks n bolts]

What about using a two color LED and a resistor? It is pretty simple. I did that with these a while back. If you get 3mm LEDs they fit nicely in the hole in the 2x2 dishes.

Very nice setup Zephyr

[1974]

Cool Yeah, you can get the LEDs in a two pin type (change direction of voltage changes colour) or three pin type (need a seperate wire for each colour)

I wish TLG would make something like this again

[Hrw-Amen]

Zephyr1934: Those do look like the kind of effect I was hoping for, but using the LEGO LEDs. But I guess that is not possible for someone with little or no electrical background.

Anyway, I have been onto Bricklink and order some of those single 9V lights and one of those directional switches to go with them. I have some 9v electric bricks and wire with connectors as well as a battery box, so we will see what that enables me to come up with.

I will post some pictures once I have something that works, or maybe even does not work(?) depending on how good or bad it is. Maybe then someone can point out what I have done wrong in that case. But I have to wait for the lights and switch first.

Yes that switch was relatively expensive. I think it is the most expensive single component I have ever bought from Bricklink. Lets hope it works! I got it from one of my regular sellers so am pretty sure it will be OK.

[1974]

If you need to switch between red and green you need two of those darn switches. You can then mechanically couple them with two 24t gears

Looking forward to pics

[Hrw-Amen]

OK, the bits came and I was fiddling around last night trying to get a working signal. I have made the signal itself but it seems that I do indeed need two switches. I would have thought that there would have been a central connection to go back to the battery box so that one way would have been green and the other red? Seems a bit of an odd idea for a polarity switch and really only gives us on or off? I am sure that I could actually use two 9V battery boxes than could be on or off but of course they are a lot bigger to hide. I will get some pictures when I have time.

[1974]

It's meant to be used with a motor to switch direction (polarity)

[Hrw-Amen]

OK, I have put some photos up. I have had to hide the wires in the back. I used those 2x2 corner bricks for the mast and used the modified plate clips to keep the wires in place. I can then use either plates or extension wires to go to the switches. I have ordered a second switch today from Bricklink. I have also included a photo of the junction in question. It is the sole bit of track I can leave in place as it is behind the chairs in my living room and thus hard to get at. The rest has to be taken up each time after I have used it.

[Locomotive Annie]

That's a great looking signal Hrw-Amen. It's good to see the junction you need to protect too. I feel very fortunate to have a site in my bedroom where I will be able to build a permanent layout and not have to take up my tracks after each running session.

[Locomotive Annie]

I have tried numerous variations of wiring using P/F lights and also 9V and 4.5V but cannot figure out how to wire what I want to happen.

Not wanting to hi-jack your thread, but I'm curious as to how difficult it was to fit a PF receiver to your 4.5volt trains. I have quite a few 4.5volt mechs and battery boxes and I'd like to be able to make use of them using some form of remote control.

[Hrw-Amen]

Not wanting to hi-jack your thread, but I'm curious as to how difficult it was to fit a PF receiver to your 4.5volt trains. I have quite a few 4.5volt mechs and battery boxes and I'd like to be able to make use of them using some form of remote control.

I had a thread about that when I was trying to figure it out. Someone had put a really useful diagram of how to wire them on Brickshelf. There is a link in the old thread,

http://www.eurobricks.com/forum/index.php?showtopic=71035&hl=%2B4.5v+%2Bremote+%2Bcontrol

I did not cut the wires on the IR unit itself as they are quite expensive so I just bought a P/F Extension cable as they are relatively cheap and used that for any cutting that had to be done attaching it onto the IR Unit. I have to say that once I had the picture of what to attach to what It was very easy. I fine wiring diagrams nowadays mean nothing to me as they seem to use totally different symbols to when I used them back in the 70's at school, but a picture is much better. Anyway, hope that link helps, the Brickshelf link is near the end of the thread.

[Locomotive Annie]

I had a thread about that when I was trying to figure it out. Someone had put a really useful diagram of how to wire them on Brickshelf. There is a link in the old thread,

http://www.eurobrick...remote +control

I did not cut the wires on the IR unit itself as they are quite expensive so I just bought a P/F Extension cable as they are relatively cheap and used that for any cutting that had to be done attaching it onto the IR Unit. I have to say that once I had the picture of what to attach to what It was very easy. I fine wiring diagrams nowadays mean nothing to me as they seem to use totally different symbols to when I used them back in the 70's at school, but a picture is much better. Anyway, hope that link helps, the Brickshelf link is near the end of the thread.

I found your diagram which explained everything perfectly http://www.brickshelf.com/cgi-bin/gallery.cgi?i=5531975

[1974]

I find wiring diagrams nowadays mean nothing to me as they seem to use totally different symbols to when I used them back in the 70's at school.

Oh, the symbols for resistors/capacitors/inductors/tubes have not really changed for a hundred years (diodes/transistors/ICs came 10-40 years after), but what you're looking at is 'integrated building blocks' containing many parts. When you look af PF elements, you look at these 'blocks', the wiring in between is simple enough and could be read by an engineer 150 years ago (allthough he'd _probably_ not understand their functions)

It's really nice that TLG have made a design that can run on 4,5V, allthough I doubt they actually designed it like that. Afterall they just use cheap 'off the shelf' parts and nothing custom made so it's more a tribute to the actual IC designers

Sorry to go off tangent

I really like your signalpost! But as you have probably allready figured out, doing this the old school way with 9V (non PF), get's pretty expensive fast with multiple signalposts ..

[Hrw-Amen]

Yes it would be extremely expensive for multiple signals. I will use it with this one as i have bought the bits and gone to the trouble of making it. I would really like to be able to do it with PF stuff but don't know how to wire up those LEDs.

What would happen if i just wired an LED directly into a battery and switch with none of that gubbins in between, would it light, explode, do nothing?

The only real problem i see with using the standard PF lights are that they have two lights on them and there is no option to just have one. Fine if you are lighting a train headlight or room or whatever but not so good for little signals where you want one red and on green or whatever.

What happens if you just snip off one of the PF LEDs so that you could build a signal like I have but with PF lights?

I considered using the PF LEDS to make two consecutive signals so that on one line the light could turn green at the same time the other turns red, but unless it is in some overhead gantry I cannot see the cables being anything like long enough for that. I suppose I could always cut them off and just stick another bit of wire in between the PF brick and the LEDs but that then again moves away from a LEGO solution, which I was hoping to avoid.

[kieran]

If you are happy to move away form standard all you need is 2 LEDS one green one red or both clear what ever you like and 2 resistors, for connection to PF switch box i would get a PF extension cable and cut that to wire up as the connection will be easy. all parts con be ordered I the UK form Maplin on line or RS excluding the PF wire take a look at the LEDS they have and add a link here I will work out the resistor you need and all you have to do is wire up, for testing you would get away with stripping the wire and twisting the legs of the LEDS and resistors to the wires, for long term use you should solder them you can get a basic soldering kit for very little money

[1974]

An LED directly to PF would explode, yes. LEDs need about 3V/10mA, meaning you'd need a resistor : (3V-9V) / 0,01 = 600R (this varies with the type of LED - but it's in the ballpark)

I can help you with the electrical parts, but wouldn't it be more fun just to do it with LEGO parts? Even it's more coslty .. you can always to it in steps, one signalpost at a time

And yes, no problem in just cutting of one PF light, but I'm sure you can find good use for it else where. Got two tracks parallel? Then you could have green light at one side, red at the other. Switch over and it's red/green