Track electrical question

[dreinecke]

Ok, I'm an IT guy, not an EE major, so bear with me:

My track is AC powered and I love it. One idea I have is to be able to better run ghost cars to give me something to race against. Right now I use a rubber band or tape on the controller in order to power the ghost cars. Due to the trick layout design, this can take quite a bit of fiddling to get right and keep the cars from de-slotting. I usually have to put some painter's tape in a few places to slow the cars down - usually on my worst curves. It works, but is very primitive and hard to get right.

So, I'm planning on perhaps using a standard household dimmer switch for the lanes. This should hopefully allow for faster and finer adjustment.

My thoughts are I would like this a little nicer than just doing a quick jumper on my controller posts. I'd also like to use this to adjust the voltage per lane for newbies. If I could put a digital display reading the voltage, that would be awesome.

Lastly, I want to put a track call button into the mix.

So, I have a rough idea of the circuit, but no idea of what type of display or call switch to use. The ones SCC have are probably what I'd consider using.

My track is hooked up like the diagram on the ac2car.org website. I've only got one tap, and use a central block to distribute power to the track and driver's stations.

I know some of you do some really slick circuit work, so what suggestions might you have?

[Nor Cal Mike]

David this would take some thought and add more wiring to you track but I have dreamed of this many times. My thought is what if you divided the power of your track into many different segments. Each segment would be supplied power from a different tap. Each tap would have adjustability in terms of how much voltage can be supplied via a series of diodes in the feed to that particular segment. Speed could be adjusted in the segment by applying more or less diodes in the line. To start up your ghost car you would simply apply full track power at the drivers station and let the diodes in the segment taps to do the rest. The cars would speed up on the straights and slow down in the turns. You could make this system user adjustable by mounting your diodes to rotary switches, one for each segment, so that speed could be dialed in to allow a particular car to handle esses at its most optimum speed. You could use rotary switches or you could simply use strings of diodes soldered together and move an alligator clip up and down the string(s) to adjust speed.

I am unsure how this would work on AC but on DC it is fairly simple. You may have to give up full AC to do it since the diodes only allow current to flow one way. But if you retained your AC power supply you would still get your DC in pulses as the current oscillates. You would still enjoy the dampening effect on torque that you are trying to get by using AC in the same way the AC2 Car racers do. Maybe some smarter than me in electrical science can suggest another way that would allow this segment adjustability to be done with full AC current.

[Nor Cal Mike]

No Jeremy, That is why I added the rotary switches. Each segment has a different rotary dial to spin up or down. This would allow you could dial in each segment to fit any particular car. You could dial all of the diodes out of the equation too when you have friends to race with.

[dreinecke]

Thanks, but I don't want to get that nuts...just a quick voltage adjuster and readout...

[jcis4me]

Aloha Dave
This is what I use 1 per lane and they work great!
http://www.ebay.com/itm/130667956239?ss ... 1439.l2649
It is DC but I am sure the guy who sells it may have an AC unit that may work. I can dial mine down to a snails crawl, to the point where the car wont go around the turns without help, I know that is too slow but I think you get my drift.
Aloha
Marty

[Nor Cal Mike]

[ElSecundo]

David, when I read your post, my thoughts went down the exact same path that Mike's did. I'm not sure how you'd vary power to the ghost car otherwise, without using a digital solution.

There are really two general ways to make the ghost car faster. Make it so the car can speed up and slow down when needed (hard to do), or make it run at a single speed, but make it harder to deslot. Have you considered adding a guide flag in the rear of your ghost car? In fact, the older Carrera Pro-X digital cars had a guide flag that was spring loaded from side-to-side, and it could be adapted to your ghost car so that the tail could swing out a bit.

[dreinecke]

Ah...now I see where I steered you all wong!

Bibbster - :teasing-binkybaby:

Mike - all great points and you are correct.

My only want is to turn down the juice easier than it is now, using my one PS.

Marty - that is very interesting as well!

So, I'll take a nap on it and let you know what I decide to do.

[Dangermouse]

"If I could put a digital display reading the voltage, that would be awesome."

I have one of these to display the voltage it says it is for DC but they may make something for AC - or at $4 if it don't work...
It works find and is more useful than the little needle on my power supply
cheers
David

http://www.ebay.com/itm/3wire-DC0-99-9V ... 4abc7344a4

[Derby City Speedway]

Hey Dave,maybe a silly idea, but what about just tracking down a old AC train transformer with the adjustable lever, I think they even had volt scale on them. And just wire that straight into the lane. Then you could just turn it off when company joins you. :?:

[RichD]

You could try using a light dimmer to drop the voltage for the lane that your ghost car is in, but you will have to be careful. Most dimmers do not have a sine wave output and transformers do not like that, they can quickly get hot and burn up. Be sure to put the dimmer after any transformer. It is also possible that the dimmer might cause the motor in the car to overheat. Start out with something that you are not fond of and check the motor after five minutes or so of running. An autotransformer would be a safer bet, but those are quite expensive.

[TsgtRet]

Dave, I'm digging back in my brain a long way (lots of cobwebs) but when I was a kid I had the Gilbert race sets. They were set up kind of like a primitive digital in that both cars could run in the same lane (they had a "random" chicane and you never knew which lane the car would choose) but the thing I remember was the controllers; they looked like miniature gas pedals and had no return spring. I have no idea what resistance they were but I do remember setting up one car at a constant speed and then "driving" the other myself. Perhaps one of these and a simple voltmeter would serve your purpose; no rubberbands, etc. Just a thought....it's amazing the stuff we have crammed in the back of our brains!

[boopiejones]

once you have the voltage regulation figured out, you can make the ghost cars handle better and run faster lap times by painting your track with magnetic paint and sticking magnets in the ghost cars. magnetic paint provides pretty subtle downforce. the motor magnets themselves won't provide enough downforce to feel, but if you stick a traction magnet (or two or three) in your ghost car, you can get it going pretty fast without deslotting.

i like nor cal mike's idea of separating the track into sections and adding diodes. for simplicity's sake, you could group the track into two sections: one power tap with full power that feeds all the straights and one adjustable power tap that feeds all the curves. or you could have two "curve taps" one for tight, slow corners and one for wide, fast corners. either way, you could get the cars running significantly faster laps than they will run if they were just tuned for the slowest corner. and they'd be more of a challenge to race against.

[RichD]

I had an AC Gilbert set as well and I remember those controllers. You could take the spring out of a regular controller. You might want to use one that can take more heat than a set controller.

[azlj]

My other hobby is animated Christmas lights. The lights are controlled though a computer and boards that apply Pulse Wave Modulation to reduce voltage. The cheapest way to do is to get a kit and build it yourself (http://www.doityourselfchristmas.com/wi ... ller_Board), I've never done that. The soldering involved scares me to death!! There are pre-built boards but they can run upwards of $200 so it that might be out other price range. The nice thing is that they are computer controlled so you can set them for each car. Some even have the ability to have triggers added. So as the car passes over a trigger (read switch, light source, whatever) it you can adjust the voltage. Not as simple as the others, but could have some pretty robust results.