Nasa Navtex H Vector Antenna PLEASE NOTE: THE PLASTIC RAIL MOUNT SHOWN IN THE PICTURE IS NOT INCLUDED.
Conventional navtex antennas respond to the electrical component associated with the navtex radio signal. They usually perform well at sea where electrical interference is low but can sometimes be overwhelmed with interference especially when in harbour and connected to shore power.
In most small craft the electrical system acts as an effective ground for the antenna but it can also be a source of interference conducted from other electrical equipment on board. Electrical interference can result in poor reception especially in a marina where the ambient level is high or at sea when poorly suppressed electrical equipment is in use.
The omnidirectional H-Vector antenna is not sensitive to electric fields but to the magnetic component of the navtex signal. As a result it is less sensitive to locally generated interference and, as it does not need a ground, it is not affected by conducted ground interference whether in harbour or at sea.
The net result is that, under adverse conditions, the H-Vector antenna can deliver a significant improvement to navtex reception. The mushroom shaped antenna is compatible with the Clipper navtex, series 2 Target navtex and with the navtex engine. It can be mounted on a cabin roof or rail mounted using an appropriate threaded antenna base. |