User Manual

44 MHX-2400 Operating Manual: Chapter 3 Configuration Options
To comply with FCC regulations,
.you must limit ERP to 36 dBm or
less.
Antenna
Before choosing an antenna, you should have some knowledge of the path
loss and the topology of the equipment. If the equipment is in a fixed
location and is to communicate with only one other unit also in a fixed
location, then a Yagi antenna is suitable. Choose a Yagi with enough gain
to ensure adequate gain margin. When deploying the Yagi, point the
antenna towards the intended target, ensuring the antenna elements are
perpendicular to the ground.
If the equipment must communicate with multiple or mobile transceivers,
then select an Omni-directional antenna with appropriate gain.
The Effective Radiated Power (ERP) emitted from
the antenna cannot exceed +36 dBm ERP.
With the MHX-2400 set to full power, ERP is calculated as follows:
ERP = 30 - (Cabling and Connector Losses) + (Antenna Gain) < 36
Use the guidelines in the previous section for calculating cable and
connector losses. If cabling and connector losses are 2 dB, then the
maximum allowable gain of the antenna will be 8 dB.
External Filter
Although the MHX-2400 is capable of filtering out RF noise in most
environments, there are circumstances that require external filtering. Paging
towers, and cellular base stations in close proximity to the MHX-2400
antenna can desensitize the receiver. Microhard Systems’ external cavity
filter eliminates this problem. The filter has two N-female ports and should
be connected in line at the interface to the RF equipment.
Weatherproofing
Type N and RTNC connectors are not weatherproof. All connectors should
be taped with rubber splicing tape (weatherproofing tape), and then coated
with a sealant.