If you want to know more about how it is done, do a search on DRR or CompPlus, plan on spending the weekend reading.

There is very specific verbage in the rulebook about types and wiring of devices. Several violators have been caught recently at big money races, they claim they weren't doing anything wrong, tech man disagrees.

Bottom line is, the tech man and the race promoter have the last say. If you are concerned at your local track, have a discussion with your tech guy and see if he is looking.