Antenna Systems
General Concerns
An effective antenna system is essential for any type of ARES/RACES station. Regardless of the station type, some basic principles apply:
- The antenna should be as high as possible, above the rooftops of nearby buildings. Height is the most important factor in the performance of the antenna system.
- Place the antenna as far away as possible from other antennas, to avoid the “desense” effect. Both vertical and horizontal separation will help.
- If the antenna is at a proper height and location, antenna gain is generally not a major factor in system performance.
- Prefer an omni-directional antenna. Directional antennas exascerbate the hidden node problem, lack flexibility, and are harder to store, transport, and deploy.
- The FCC requires an RF safety evaluation of every station. The antenna system must include barriers or warning devices to keep people out of the unsafe area.
- Do not operate any station when lightning is threatened. Permanent stations should have lightning arrestors and be properly grounded and bonded.
- Minimize the cable length and the number of cable connectors, and weatherproof all connections.
Specific Station Types
Antenna system details depend on the type of station.
(Handheld radio antennas are discussed on the handheld radio page.)