F-3990
This VHF antenna is designed for applications that require peak performance in the 136-174 MHz while tolerating a VSWR around 2.0:1.
This antenna has a loading coil between the radiating element and the base. This coil increases the electrical length and makes the antenna perform electrically as a 1/4 wave antenna, but shorter than a regular 1/4 wave antenna. Typical gain, when mounted on a ground plane, is comparable to a full 1/4 wave. Mounts on NMO.
The upper element is made from a brass wound cable with a flexible shaft core, well sealed using rubber shrink material. This solution offers a high reliability and prevents breakage or brittleness. Other frequencies are available upon request.
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