Road Loop Antenna Installation
© 1999, AXCESS
TM
Inc.
750.001.003
Revised June 1999
63
Road Loop Lead-in
Dual binding post-to-
Male BNC Connector
Figure 25 Post to Male BNC Connector
Step 13:
If any third-party equipment will also be installed, lay it out
at this time.
Step 14:
Turn on the system and adjust the ATU according to the
instructions in the
Maximizing Antenna Performance with
the ATU
section, page 73.
Step 15:
Using an LED Test Tag, ensure that the transmit field of
the Road Loop extends 7 or 8 feet above ground level and
15 to 24 feet horizontally. The Road Loop Antennas with
greater widths have larger fields.
Step 16:
After ensuring proper operation, remove the wire loop and
concrete nails to allow cutting the groove into the roadway.
Common Layout Problems
If the transmit field of the Road Loop Antenna does not have the
proper range, check the following:
•
Is there power-line interference (or similar) directly under the
roadbed? If so, the Road Loop Antenna may have to be moved.
•
Has part of the Road Loop Antenna inadvertently been twisted?
If so, correct the condition.
•
Does lack of continuity with a multimeter indicate a break in the
loop or lead-wire? If so, correct the condition.
•
Have all connectors been correctly installed?
This is frequently
the cause of problems
. Correct if necessary.
•
After checking these items, re-check the ATU tuning again.