Can anyone provide a checklist of possible causes of false finishes? We use ALGE through beams and have had two races where the finish was several hundred feet from our building and we had many false finishes. Could it be simply the distance?

To me, distance would would only cause impedence to increase, which would lead to missed finishes- not false finishes. However, an intermittent short in the line might cause this. Water in the cable or EMI interference (from a chairlift or something similar) would probably be the cause of this.

Look at your photocell as well. Snow buildup on the sensor might be an issue, as would lense fogging. Emitter/detector alignment would certainly need to be checked, as Alge sensors are pretty sensitive. It's easy for a loose mount to cause alignment to drift. I use a lazer level to make sure I'm more or less dead-on at the start instead of just on the perimeter of aligned. Check the distance between the sensors as well- although it's not as critical in most race venues with a thru beam set as with the reflector style. What about batteries and battery connections? New batteries and clean terminals are also a good place to look.

Other than that, I'm out of my league.

When in the run were your False Finishes happening ? ? Were they all about the same place / time for the racer.

What else was happening ? What was the weather ? Snow - cold / warm ??

Did the same person set up your eyes .. from when they did work OK ?

Anything at all NEw ADDED TO YOUR SET-UP ??

It was warm and sunny at one race and cold rainy and foggy at the other where we had this problem. The same person did not set the eyes.
I suspect a short in the complicated improvised connections that were made, they wre expoased to the weather and may even have had snow in some of the connections. We are trying to get the differnet hills we time at to go with a standard wiring set up.

Is this the instance where you also reported that the needle on the S4 was swinging during the race? That would have indicated a short, reversed polarity, or a cell out of alignment. In general, anything but a solid green needle should be cause to correct the problem prior to starting the race. Look at the timing tape. I think you will find that the "false finishes" happen at a regular interval. Depending on the D F (delay finish) setting on the S4, you could have gotten quite a few extra pulses on a regular basis.

Strangely enough, the race where I noticied the needle on the S-4 bouncing went very well, no issues. We had the false finishes at previous races.

However, the S-4 needle may have been bouncing at those races, I did not notice since I am on system B with the Timy. I will of course be watching for that now.

Considering the large number of false finishes as well as the complicated improvised wiring connections at the two races in question a short or polarity issue is not only possible but likely.

If there is a swale in the middle of the run such that the snow is very close to the primary ( lower) beam could that cause false finishes? That was present at both races as well. I would love to have a check list of possible causes so I can trouble shoot this if it comes up.