I'am based in Mexico , I'm 72 years old, Inglish is my second language ,been a Bracket Racer for a long time, I still race my Vega once in a while here in north part of Mexico, across the border from Del Rio TX. I just got started 5 years ago, making the Trees first than pre-stage & stage sensors made for drag racing purpose only , (not Industrial purposed sensors)and I call my self Green Light timing Systems, I focus on Low budget, basic timing systems, with only : A Timer Box, pre-stage , stage and finish, 3 wire cable for the long run(1/8 or 1/4 mile, )I also designed a wireless system ( no cable for the long run), I use this method (wireless, for Street racing, a starting tree with just a Green Light and finish sensors(One for each Lane) with dual purpose, to detect who cruses the line first? and send a radio signal to the starting tree to announce the winner by blinking the light of the winner lane) No timer on this setup. And working with this tiny radio transmitters gave me the idea that is what is being use on these "Tree reading device" ....The Radio receiver is so small with antenna integrated is about 1" wide x 1 1/2" Long and just 1/4" thick it can be hide any where in the car , the range of this setup is about 1/4 mile , the only visible thing will be 2 tiny, 22 awg wires going to the Delay box to activate it , the same two wires coming from the steering wheel transbrake button wired in series. it will very hard to find this device, that's why I suggest crating interference to overload this sensor(give it plenty of what is looking for at the wrong timing).
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