User's Manual

905U-K Radio Telemetry Module User Manual
 ELPRO Technologies Pty Ltd 2001 Page 22
gain of the antenna. Also note that YAGI antennas normally have a drain hole on the folded
element - the drain hole should be located on the bottom of the installed antenna.
The YAGI antennas may be installed with the elements in a vertical plane (vertically polarised)
or in a horizontal plane (horizontally polarised). For a two station installation, with both
modules using YAGI antennas, horizontal polarisation is recommended. If there are more
than two 905U-K modules transmitting to a common 905U module, or there is dipole or
colinear used in the system, then the YAGI antennas should have vertical polarisation.