RF levels between flat panels

I use a set of 900MHz flat panel antennas connected to the finish line T-Links and the timer in the tower. Never have a problem with signal on the left lane but the right lane seems to be much more sensitive to surrounding objects and where we set up. This does not seem to be a problem when the track is 300 foot long but does happen a lot when the track is 1/4 mile. Both left and right lane finish antennas are line of sight to the tower and no chain link fences or large structures nearby. Should I be setting up the antennas differently for the 1/4 mile setup? I must be doing something wrong.

There should be no difference in setup for 300FT or 1/4 mile as far as the Flat Panel Antennas except for height off the ground. The farther the distance between antennas, the higher the antennas should be off the ground since the signal spread out more with greater distances.

One thing to check is the orientation of the antennas when mounted. Most high gain antennas have a horizontal orientation and a vertical orientation, that is, how the signal shape \'looks\'. The Flat Panel Antennas RaceAmerica sells have three mounting studs on the back of the antennas and a label showing orientation (an arrow to show where up is). When holding the antenna as it would be mounted and viewing the backside, the three studs would be located at upper left, upper right, and lower right with the orientation label in the lower right. No stud in the lower left of the antenna back plate as shown in the photo.

Antenna Orientation-400.jpg
RaceAmerica did find a limited number of antennas shipped from the manufacturer with orientation labels applied incorrectly. This caused some low RF signal levels and was corrected by changing the mounting orientation of the antenna and moving the mounting label to the correct location on the back of the Flat Panel. The best way to ensure proper mounting is to match the mounting stud locations as shown in the photo.

For additional background on RF communications, check out the Technical Article on Wireless Communications on our website at:

*** RIGHT CLICK THE LINK BELOW TO OPEN IN A NEW TAB ***

http://www.raceamerica.com/articles/art002.pdf

I checked some photos of our setup and noticed the antenna label is correct on the right lane antenna. I also noticed the antenna was mounted wrong at our last race based on what I can see in the photos. Whoever put the antenna up, they mounted it rotated 90 degrees to the left. I wonder how often they mounted the antenna wrong and that may be why it works fine one race and not the next! Will do a sanity check next race ...

We had a 2-day race day this part weekend and RF levels were up and no issues both days! Made double sure all three flap panel antennas were mounted the same as the picture. We must have been mounting the antenna wrong without knowing it. Simple stuff.