Magnetic Loop antennas

What is a magnetic loop antenna?

"Magnetic" because they take the magnetic component of a electromagnetic field, in contrast to the normal standard antennas (e.g. Dipole, Yagi, Vertical-antenna), which are in resonance only on the electric component.

Magnetic antennas can be created very compactly. Ideal in areas of limitated space or where mobility is required e.g. boats. No radials are required. The radiation is always the same, irrespective of the distance to the ground.

The capacitance can be varied by a motor and can be adjusted to the best SWR via a control unit in your shack. In spite of their compact size, the antennas are resonant in a wide frequency-range - do you know of any antenna which has a diameter of just one meter (ca. 38 inch) but a frequency range of 40m ... 10m without gap?? Take this one...

The antennas provide a small bandwidth on their resonance frequency. They have the advantage of less harmonics, and the effect of an additional preselector, focusing on just the required signal, ignoring non-required signals and intermodulation.

Automatic Control Unit

Particular properties of our loop-antennas

The loop is made of aluminium. Even the smallest antenna has a 50mm ( 2 inch) diameter of the tubing. Because of the large surface area there is less loss of gain. Both ends are welded on the socket, no screw connections so no contact resistance.

The tuning capacitor on our loops is not a simple variable capacitor but a big variable plate capacitor of aluminium with an air-dielectric. Both plates are also welded directly to the loop and indestructible on high power! The distance between the plates is 14mm (ca. 1/2 inch) on the smallest antenna.

A weather resistant actuator opens or closes the loop and thus tunes the plate capacitor (SWR tuning).

Automatic Control Unit

Tuning of the antennas is done with either a manual or an automatic control unit. The control units have a 230V power supply integrated.

Automatic control unit
The automatic control unit has a tuning circuit installed and is operated with a small keyboard: just enter the desired frequency, wait a few seconds for automatic tuning of the antenna and go. No trying, no lost notes on settings, no checking with the SWR meter. The current frequency and SWR is shown on the LC display. Maximum power load is 250W with the automatic control unit! A 230V power supply is included in the control unit.

Loop Antenna Presentation and Instruction Manual
We have a small but extensive, 50 pg. booklet (english) about our Loop antennas, with explanations about the antennas, diagrams, sizes, installation tips etc. If you are interested pls. send a letter with your adress and 5,00 Euro in cash to our adress, we will send you the booklet right away.

Or download this manual booklet nowLoop-Manual (PDF, 5MB, english).

BABY Loop: 6.6 to 29.8 MHz

The smallest and most popular selling loop-antenna. Diameter is only 1m (ca. 38 inch). For this antenna space is not a problem: on the balcony, on the roof. The gapless frequency-range is 6,9 up to 29,7 MHz. It comes ready to use with mast clamp. Please order the control unit separately.

MIDI: 3.5 to 14.5 MHz

Midsize antenna, ideal for 80m up to 20m with continuous covering, manufactured on a stable aluminium reed with a diameter of 75mm (ca. 3 inch). Loop diameter is 2m (ca. 78 inch), can be mounted without radials, like all loop-antennas.

Controlwire for Loop antennas

The Magnetic Loop antennas with manual tuning require four wire for control, the antennas with the automatic controller require two wires. The smallest cable we offer is a six wire cable. With this cable you could 2x2 wires in parallel for manual tuning, or 2x3 in parallel for automatic tuning. Due to the enlarged diameter very long cable runs are possible.