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Chapter 6: Installation
Typically, a Repeater site will employ an omni such that it can readily receive an RF transmission from one direction and be able to
readily transmit it in another.
If an application involves Remotes that are not stationary (e.g. mobile application), all sites would likely use omni antennas so that
wherever the units are, there will be antenna pattern coverage.
The path calculation (see Section 6.1) will determine the antenna gain requirements. Refer to the beginning of this section to
review the various factors which must be considering when deploying a network. Do not discount the importance of the
REQUIRED HEIGHT for the antennas within your network.
6.2.2 Coaxial Cable
The following types of coaxial cable are recommended and suitable for most applications (followed by loss at 900 MHz, in dB,
per 100 feet):
• ThinNet Cable, RG-58, 10BASE2, PVC (NEC CL2), 5-ft. (1.5-m), product code LCN300-0005
• ThinNet Cable, RG-58, 10BASE2, PVC (NEC CL2), 10-ft. (3.0-m), product code LCN300-0010
• ThinNet Cable, RG-58, 10BASE2, PVC (NEC CL2), 60-ft. (18.2-m), product code LCB300-0060
For a typical application, LCN300 cable
may be suitable. Where a long cable run is required and within networks where there is
not a lot of margin available, consider using a cable with lower loss.
When installing cable, do not damage it (be particularly careful with respect to not kinking it at any time) and to secure it
properly. Also be sure to affix the connectors properly—using the proper crimping tools—and to weatherproof them.
6.2.3 Surge Arrestors
The most effective protection against lightning-induced damage is to install two lightning surge arrestors: one at the antenna, the
other at the interface with the equipment. The surge arrestor grounding system should be fully interconnected with the
transmission tower and power grounding systems to form a single, fully integrated ground circuit. Typically, both ports on surge
arrestors are N-type female.
6.2.4 External Filter
Although the MDR100A-R5 or MDR112A-R5 is capable of filtering-out RF noise in most environments, there are circumstances
that require external filtering. Paging towers and cellular base stations near the MDR100A-R5 or MDR112A-R5’s antenna can
desensitize the receiver. The MDR100A-R5 or MDR112A-R5’s external cavity filter eliminates this problem. The filter has two
N-female connectors and should be connected inline at the interface to the RF equipment.
CAUTION: To comply with FCC regulations, the maximum EIRP must not exceed 36 dBm. All installation, maintenance, and
removal work must be done in accordance with applicable codes.
