User manual

User Manual
man_905K_1.10.doc Page 25
referred to as a repeater. This module may also have input/output (I/O) signals connected to it
and form part of the I/O network.
An antenna must be connected to each 905K module using the SMA connector at the top of the
enclosure. It is important to weatherproof this connection by wrapping with waterproofing
tape (for example 3M 23 tape).
The available antennas to be used with the 905U-K units are:
WH900 Whip antenna for mounting directly onto the module - operation up to ½
mile (1 km)
CFD890EL 0 dBi Dipole antenna with 15’ of Cellfoil cable and SMA connector
SG900EL 5dBi Colinear omni-directional antenna with N-type connector
SG900-6 8dBi Colinear omni-directional antenna with N-type connector
YU6/900 10dBi Yagi directional antenna with N-type connector
YU16/900 15dBi Yagi directional antenna with N-type connector
The available accessory cables for use with the 905U-K units are:
CC10/900 33’ (10m) low loss Cellfoil cable, 3dB loss
CC20/900 66’ (20m) low loss Cellfoil cable, 6dB loss
The following table shows which cables can be used with the different antennas:
Antenna North America Australia/NZ
SG900EL any cable CC10 or CC20
SG900-6 any cable CC20
YU6/900 CC20 external cable with loss > 9dB
YU16/900 external cable with loss > 9dB should not be used
Connections between the antenna and coaxial cable should be carefully taped to prevent ingress
of moisture. Moisture ingress in the coaxial cable is a common cause for problems with radio
systems, as it greatly increases the radio losses. We recommend that the connection be taped,
firstly with a layer of PVC Tape, then with a vulcanising tape such as “3M 23 tape”, and finally
with another layer of PVC UV Stabilised insulating tape. The first layer of tape allows the joint
to be easily inspected when trouble shooting as the vulcanising seal can be easily removed.
Where antennas are mounted on elevated masts, the masts should be effectively earthed to avoid
lightning surges. Where the antenna is mounted outside of an industrial plant environment,
a coaxial surge diverter is recommended. If the antenna is not already shielded from lightning
strike by an adjacent earthed structure, a lightning rod may be installed above the antenna to
provide shielding.