VAS Helical 5.8GHZ - 71mm LHCP SMA

VAS Helical is a directional antenna with left-hand circular polarization LHCP, an SMA connector, and a gain of 9.5 dBic for the 5600-5980MHz band. It is intended for the receiving side of FPV goggles, a ground station, or a diversity receiver. The frequency range covers all common 5.8GHz channels.

The Helical antenna has an element wound into a helix above a metal reflector. Air between the turns serves as the dielectric and has lower losses than fiberglass in flat patch antennas – the helical therefore achieves higher efficiency at comparable dimensions. Gain is determined by the number of turns; this model has five. In the VAS lineup, it is the middle size between the three-turn model with 7.5 dBic gain and the ten-turn Black Cannon with 12.5 dBic.

The radiation beam is 105°, with a -3 dB drop occurring at an offset of ±32.5° from the axis. For a directional antenna, this is a wide beam. The antenna is tolerant of model movement and head rotation and does not require precise aiming, which makes it ideal for mounting directly on goggles. Even so, it remains directional and we do not recommend using it as the only receiver antenna. The ideal setup is a diversity receiver combined with an omnidirectional antenna, for example VAS Ion Pro or Victory (sold separately). The directional antenna provides range and signal penetration through trees and buildings, while the omnidirectional antenna covers the nearby area, takeoffs, and landings.

Circular polarization suppresses reflections („multipath“) and signals with opposite polarization. The manufacturer-specified axial ratio is 0.82.

The helix is made from insulated wire wound on a plastic support above a circular reflector. The antenna connects via a semi-rigid coaxial cable with a straight SMA connector. The cable holds its shape, so once mounted on the goggles the antenna does not need additional support and does not tilt down. A reducer for RP-SMA receivers is included. The supplied VAS Finger Wrench plastic tool is used to tighten the connector without tools.

Video Aerial Systems (VAS) is an American company focused on antenna development and production. It was founded in 2011 by Alex Greve, known in the FPV community as IBCrazy. It holds several of its own patents and their antennas are among the very best.