S4 and RLS1 false finishes

Interesting. I will pass your observations along to the ALGE factory. The ALGE reflector employes a deeper surface than reflectors availible here in NA. It is worthwhile to note that your idea with the sun shield for the reflector worked. Thanks for sharing the tip.


Posted by Fred Patton

We did encounter similar trouble with our RLS1 cells several years back, and it was a bit difficult to trouble shoot. My first guess is that you have the well documented 'red cord' DIN plug contact problem. A bit of corrosion in the male jumper or female plug on the cell (or wind that jiggled the connection perhaps) was giving us FITS with false finishes, although everything tested fine in our pre race set up. The bannana plug connection has truly proved itself to be superior and bombproof over thousands and thousands of trouble free runs. At the Jackson Hole Race Dept. we own 6 Alge RLS1 cells and have abandoned the DIN connection - where the power supply is external - on all of them. We use a brand new 'C' cell every day for all sanctioned events (real cheap insurance!), and recharchable nicad 'C's' for our 7 day a week NASTAR. Freds comment about the fried circut board is of course correct, and certainly could cause your FF problem, but remember that the damage can occur inside your finish building as well as outside on the finish line. All it takes is to put the cells away for the day on a desk top with the lenses pointing towards the setting sun for a few moments My suggestion is to always power up your photocells internaly, and if you have the
equipment run one 'thru beam' (takes TWO RlS1 cells) as your primary, and a cell and reflector as part of your separate redundant back up system. Abandon the three wire 'DIN' connection entirely and go with long shank male bannanas on two conductors - one pair - for your connection to the S-4 or whatever clock you use. This solved our frustrating and painful false finish problem totally, and it has never re occured in about 5 seasons of 7 day a week racing in Jackson Hole.


Originally posted 28 Feb 2001 by Nick Anderson
nicka@jacksonhole.com

Nick

You make some great points, and I appreciate the time that you spent providing the group with your answers. Unfortunately, most of my RSL1's don't have the banana plug on them, so I would have to spend some time modifying them.

I did some testing yesterday while running our club championships. The setup was similar as the week before, and I was able to look at the same time frame as last week.

I was able to see that there is some facts supporting the 'sun blinding' part of my argument. We are at 44 degrees N and the sun is somewhat low in the ski. There is an acute angle that will cause a beam out of the reflector from the sun. You can see this if you look at the reflector from the area of the transmitter/receiver. The optics in the reflector are not perfect. Yesterday, I cured the problem by adding a sun shade to the reflector.

We ran 400 racers through without one false finish yesterday.

Mike Walker mike.walker@home.com


Originally posted 4 Mar 2001

The knob on the back of the S4 is for headset volume. The finish delay is handled by using the toggle switch. When you are in program 3, all delays are the same and are altered for the finish (Df).

The delay knob on the photocell is really only used when the object that you are timing takes a long time to pass through the cell. Horses, canoes and shells, cars, etc. The higher the setting, the longer it will take the cell to reset and to allow another pulse to be sent. If you have the cell set on max (2 secs) you will notice the meter on the S4 will flip back and forth as if it is shorted. I prefer to use the Df setting in the timer. Many software packages have adjustable delays as well.


Originally posted 26 Feb 2001 by Fred Patton

Yes, we had DPU414's installed, so no current drain there.

The RLS1's where installed at the south, pointing north. Their shields where both extended. Both where connected with a 3 wire red cable (not banana plugs). I will look to see if there is any internal damage. On the newer RLS1, we did install the battery and turned the switch on.

If sun did make it internally into the RLS1's, then it would have had to have come from the reflector at the north end of the finish line.

2 things I need to understand:

1) On the delay control on the RLS1's, how do I make the best use of it. What am I actually delaying when I increase it?

2) On the back of the S4, there is a variable adjustment. Again, how do I make the best use of this.

Great help here all!

Many thanks!

Mike Walker


Originally posted 26 Feb 2001 by Mike Walker

The S4 timer is designed to progressively shut down to allow you to finish the race. Page 7 of the manual details the voltages and the meter condition. The meter should always be in the green as a matter of course. 7.7 volts should have been ample to power the cells and run the timers. You did not mention the type of printers
used, I assume they were Seiko DPU414s which do not draw any battery power from the timer.

The photocells are the area that I would investigate. The cells are designed to run either on the internal battery with banana plugs -OR- with direct connection with the "red" cable. You did not mention how they were powered.Peer into the cell through the lense and see if you can see any melting of the plastic. The sun can enter
the body of the cell just like a magnifying glass. If it hits the recieve diode it can overload it. Did you have the sun shields fully extended? We have seen this king of melting and overloading out west. Where were these cells installed?

We would certainly like to see these cells if there is any question as to their utility. Having a global failure like this is certainly strange but appears to have happened consistently to both cells.


originally posted 26 Feb 2001 by Fred Patton