At a FIS race last weekend, we were using the Tag HL2-32 through beams with the sync cable. After a flawless first run, we stopped getting finishes on our primary setup. In between runs, we swaped the wires (black to green, green to black) going into the primary photocell and then received finishes. We finished the rest of the race with the reversed wiring. Any ideas on why the polarity would switch in the middle of a race like that? We fixed it for the time being, but would like to get to the root of the problem ASAP. Any input would be appreciated. Thanks.

I made a discovery about the TAG HL2-32 some time ago during a race. First of all, you should always respect polatities on all TAG equipment, this is especially important if you are using optocouplers and headset amplifiers in the installation. My discovery was that I was getting false impulses from the photocells, this in turn was caused by a broken wire in the sync cable between the transmitters. The problem showed up about 1 hour after switching the system on, possibly caused by drift in pulse frequency between the 2 transmitters. After repair, no more strange behaviour.

Thank you for the input, Bajaz. Since this just happened again today - during the middle of a race run - we are switching the pairs to see if the anomily continues.