PortaTree Snowmobile Racing - Manual

BRACKET AND SUPPORT
INFORMATION FOR PHOTOCELLS
AND REFLECTORS FOR SNOWMOBILE
RACING
The Photo Cells for the sport of snowmobile racing should be set up as follows:
Height -- Start E.T./Guard Beams 15 inches high
All other locations 12 inches high
PRESTAGE - - STAGE - - GUARD SPACING
7 Inches between Prestage and Stage (if using 3 beams)
15-24 Inches between Stage and Guard beam
**We recommend 15 inches between stage (prestage) and start E.T. (stage)**
The reflector type infrared photo cells should be mounted on rigid supports so that
they will not be affected by the wind or melting ice and snow. Even though they have an
ample deflection angle to avoid misalignment problems, it is best to avoid the problem
before it happens. Usually misalignment happens when the detector is on the edge of the
target. Read alignment procedures to prevent this problem.
The reflectors should be mounted in the center of a 12-inch piece of plywood that
is painted flat black. The reflector can be shielded from direct sunlight by a small coffee
can that is mounted on the plywood first and the reflector is located at the bottom of the
can. Make sure the can is painted flat black. The detector can be shielded from direct
sunlight by locating a hood over it. This can be made from a piece of PVC pipe split
down the length of the pipe. Reflectors should also be mounted very rigid.