95/TX Operation & Maintenance Manual, Revision 1.0
Page 15
YAGI DIRECTIONAL ANTENNAS
Yagi antennas are directional along the central beam of the antenna. The folded element is towards the
back and the antenna should be “pointed” in the direction of the transmission. Yagi antennas should also
be mounted with at least 2-3’ of clearance from other objects. Mount the Yagi antenna as shown for
maximum RF transfer.
Figure 4-4: Yagi Directional Antenna
In networks spread over wide areas, it is common for a central receiver / controller to have an omni-
directional antenna (such as a collinear) and the remote GAMAX/TX monitor to have Yagi directional
antennas. Care should to be taken to ensure the Yagi is aligned correctly to achieve optimum
performance.
COAXIAL CABLES
When installing a coaxial cable between the 95/TX and a remote antenna, constructing a loop of cable
below the antenna is always recommended. The loop allows water to drip off the bottom of the U
instead of into the connection, reduces installation strain and provides spare cable length in case later the
original connectors need to be replaced.
Avoid installing coax cables together in long parallel paths. Leakage from one cable to another has a
similar effect as mounting an antenna near another antenna.
SURGE PROTECTION & GROUNDING
Voltage surges primarily enter the 95/TX Alarm Station via the antenna connection as a result of electrical
discharge in the atmosphere. Electrical energy follows the most direct path to earth and the best
protection is achieved by “draining” the surge energy to earth via an effective earth ground. Wireless
Always mount Yagi antennas with the
primary elements
oriented in the same
direction
as any omnidirectional
antennas in the same system