This device provides a means of reducing or eliminating common-mode noise from an antenna feedline, resulting in a considerable increase of the received signal quality. Common-mode noise is generated by computers, lamp dimmers and other electric or electronic appliances. Such noise can be a problem especially in the lower portions of HF spectrum, where weak signals can be sometimes completely masked by assorted buzzes and other unwanted noises.
The Common-Mode Choke can be also very useful to provide an alternative earthing point for an active antenna, if the antenna itself cannot be grounded due to its location, or its ground connection is inadequate. (Frequency range DC to 30 MHz / 50 ohm / Rugged weatherproof construction )
The WiNRADiO WR-CMC-30 common-mode choke is inserted in the antenna coaxial feedline close to the receiver, in order to "choke" off common-mode noise currents and passing them to ground without affecting the useful signals between the antenna and the receiver