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Radio Antenna Siting
Crowded antenna locations can result in reduced range.
 
For Licensed Information Radio Stations
Marginal Antenna Placements

Antennas surrounded by poles, wires, large structures or trees cannot generate their full signal potential.

 
Superior Antenna Placements

Compare against these antenna placements, which are in open areas of a yard or roof with no lateral obstructions.

 

Ideal Antenna Siting
The antenna may be installed on a 20’ pole located adjacent to a host building. We recommend a 50’ minimum separation between the building and the pole. (The pole may be provided by you or by us, depending on the contract.)

The building should have generator power backup, if the application is for public safety

The pole should be placed in the yard of a builiding, on a side in which there is minimal paving or sidewalks for the buried cable to cross . . . in a yard area with adequate room for the pole and buried groundplane (if required) . . .in an area in which obstructions taller than 20’ are farther from the pole than they are tall (ex: 35’ tall tree is at least 35’ away). See diagram below.

If there is no suitable ground location and if the building has a flat roof, the roof may be considered under certain circumstances.
Consult with us.

Positioning the Antenna Near Obstructions that Exceed the Antenna Support's Height
 
Ground Installations:  the distance to obstructions (X) should exceed their height (Z) above ground.

Flat-Roof Installations:  the distance to obstructions (X) should be at least twice their height (Z) above the roof.

Antennas installed closer to obstructions may evidence signal degradation, particularly if operating on lower AM frequencies.
Lightning Protection
Destroyed AntennaArrestor
Destroyed AntennaArrestor that Protected System Electronics from Lightning Damage

Lightning protection is important. Though damage seldom occurs due to the fact that Information Radio Station antennas are not often installed high above the ground, lightning can strike them; and when it does, it needs to be directed to the ground so damage to connected electronics does not result. Information Station Specialists provides a lightning arrestor in every one of our systems that redirects lightning and generally will reset immediately so operation of the radio station is not interrupted.

The above photos show a rare catastrophic multi-pole lightning strike that occurred at the Information Station operated at Los Alamos National Lab in New Mexico in 2022. The antenna was totally destroyed (left photo) but the arrestor (pictured at right) protected the system’s electronics from damage, directing instead the charge into the aluminum plate and to the ground.

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For License-Free Information Radio Stations
InfOspot Range Extender Outdoor Antenna and Tuner Setup     
Good InfOspot Antenna SetupsBad InfOspot Antenna Setups
                        Image 1                               Image 2                             Image 3                               Image 4                               Image 5

The InfOspot antenna and tuner should be installed in an open area, mounted to the very top of a pole or mast that extends above a support structure, 3-5 feet minimum. (See Images 1 & 2, above.)

It should not be side-mounted directly to a support structure (wall, tower leg, gable, etc.), allowing the antenna to parallel the support structure. The antenna itself also should not be allowed to parallel the mast or pole to which it is attached as in Image 4, above). This will cause the antenna’s signal to be dissipated into the mast or pole.

For example, attaching the Range Extender Outdoor Antenna and Tuner to a short stub just (as in Image 3) above a support structure or alongside a wall, eave or gable can yield less-than-ideal results. Instead, attach it to the top of a mounting pole or mast that allows the tuner and antenna to be raised fully above the support structure.

Installation in the general vicinity of a much taller structure (as in Image 5) will limit the range of the broadcast significantly. Taller structures should be at least as far away from the InfOspot antenna as they are tall. (A 50-foot tree should be separated by a minimum of 50 feet, laterally.)




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