PortaTree Downtrack Infrareds, Infrared Stands & Foam Blocks - Manual (Page 2)

Step 7: Mount the sensor boxes to the cement pad directly under the location of
the pull line and at the height that was determined in Step 5.
Step 8: Mark the center of the race track directly under the pull line where the
Foam Blocks will be located. Mark either side of the location of the foam block
so that it will be easy to locate. Remove the pull line
Step 9: Use a tape measure to determine the exact center of the track by
measuring wall to wall (guard rail to guard rail) and locate the foam block exactly
in the center of the track. Make sure that the reflectors on the foam block are
directly in line with the marks that you have made under the pull line in step 7.
Step 10: Mount the Foam Blocks using Velcro Fasteners. Use Silicone RTV to
place one part (side) of the Velcro on the bottom of the Foam block. You must
use 3 – 2 inch wide strips on each Foam Block.
Step 11: The other side of the Velcro must be siliconed to the track and also
must be fastened with nails or screws to the track so that they will not be pulled
off when the foam blocks are removed. The foam blocks are porous so the
Velcro will stay fastened to the foam blocks even when removed.
Step 12: Align the infrared sensors from side to side and up and down until the
maximum pulse rate is attained on the sensor alignment light.
Repeat Steps 1 through 12 at each location on the race track.