infrared timing system question

[btaylor]

Not sure this is the right forum to ask this, but its for a 1/32 track.
I think I have finally decided to go with the infrared timing system from trackmate,my question to anyone who has installed this system is about the overhead ir emitters . I want to string the ir leds over the track on a cable or stiff wire to simulate a power cable or communication line of some sort. I do not want a conventional light bridge as its going on a simulated dirt oval and would look out of place,My question is can you use small enough wire to to hook up six sensors to hide as a scale power line? where does the resistor go ? and can it be mounted closer to the power source under the table
I don't have a picture of this setup,but it would have a wooden power pole on each side of the track,with six sensors,and scale checkered pennants between each ir bulb,seemingly looking like a lighted starting line,but actually being the light source for the in track sensors.
any ideas?
Bob

[RichD]

You would probably be better off using dead strips if you do not want to have a light bridge. The IR emitters need to be aimed at their respective sensors, that might be difficult with the arrangement that you have proposed. The dropping resistor(s) do not have to be located where they would be visible, they can be located anywhere in the circuit. There are several ways that the emitters can be wired. The emitters can be wired in series with a single dropping resistor, also in series. That scheme would be best in your case, except that if an emitter failed they would all go out and the defective one would be difficult to find. The usual way to wire the emitters would be to have them in parallel with a dropping resistor for each one. In that case if an emitter failed only one lane would stop counting. Another option would be to use emitter/sensor pairs that look across the slots.

[Modlerbob]

I agree that if you go with IR sensors a rigid mount is critical. How about disguising it as a pedestrian bridge over the track.

[btaylor]

The now nearly permanent mounted plastic track would make it close to impossible to modify for dead strips,and I really don't want anything over the track,so I thought to minimize the visual impact,i could try and make it look like a light string illuminating the starting line. I can make this rigid and aim the sensors at each other with no problem, I am only concerned with the potential bulk of wires being to much out of scale.

[HomeRacingWorld]

You could build a smaller version of the this:



The "bridge" does not have to be this large.

You could make a smaller in diameter support. The LED's and harness can be made to mount without a lot of excess wire.



You can see that there is a lot of room here. I made it like this for easier install and replacement of sensors when needed. But it can be reduced in size.

You can mount it on the far side of the oval, and you don't need another "leg" either. Using PVC pipe like this:



This made the "bridge" sturdy enough where I did not need the support leg. I made them for show mostly.

The you could drape flags/signs and it still would look pretty good.

[btaylor]

I ordered the trackmate system per Harry's article, After seeing the amount of space required for the overhead sensors,i believe i can put them in a small piece of channel to make them look the way i want. either way i will have a much needed timing system on the track.
i will post pictures of the overhead when i get it built,should be a challenge to make it look like it belongs there!
hopefully with some weathering and creative banners/pennants? i can pull this off.
thanks for the help on this guys.
Bob

[DAVE]

Have you tried the system without the emitters? There might be enough ambient lighting for
the sensors to trip. As I stated in some other threads on this subject, I have been using the
IR sensors on my drag strip without additional lighting, even outside at night with just area
floods lighting the whole back yard. The software has diagnostics that will show if the sensors
are responding with the ambient lighting.

[btaylor]

I have not received the system yet,as i just ordered it sunday. i suppose i could try it without if it wont damage anything. at this point i am almost looking forward to the challenge of hiding the ir's in plain site!
i really need a dependable no bs system regardless of the minor obstacle of the overhead.

[DAVE]

You won't damage anything. In the software is a diagnostic section that will show you if the
sensors are working. You get a green bar for each sensor if it is working, a red bar if it is not.
If the bar shows green, cover the sensor and see if it turns red. If it does, it is working
properly. If the bar shows red, shine a light on it and see if it chages green. If it does, then
you need additional over head lighting.