The magnetic loop antenna is a high-Q tuned antenna with a very narrow pass band?typical range is 10-25 KHz. The performance of the magnetic-loop antenna is similar to a ? wave dipole.
The magnetic loop antenna does not like being near metal of any kind. In fact, so sensitive is the loop to metal, that the best SWR is achieved by running the coax directly down to ground level and then away from the antenna, perpendicular to the antenna?s face. If mast mounting is desired, the mast must not be made of metal. The loop is also sensitive to the presence of one?s body, causing a slight de-tuning of the antenna. This is why some magnetic loop designers have experimented with low RPM DC or Step motor remote control. With practice, the user will be able to compensate for this de-tuning factor. Support structures for the loop should be comprised of unpainted wood, plastic or fiberglass.
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