ANTENTOP- 01- 2012, # 016

Two Receiving Magnetic Loop Antennas from Old Magazines

Very often it is possible to find something interesting and unusual while going around old magazines. Below there are two interesting design of the Magnetic Loop Antenna.

Loop Antenna with Eight Ferrite Rods

Credit Line: Funkschau # 6, 1958

Figure 1 shows a Loop Antenna with eight ferrite rods. To compare with an usual magnetic loop antenna coiled on to a single ferrite rod the multi- rods antenna has advantage in effective height, diagram directivity and selectivity.

 Figure 1 Loop Antenna with eight ferrite rod

Compact Ferrite Tuned Magnetic Loop Antenna

Credit Line: Radio Electronics, December, 1955

It is very often a magnetic loop antenna is tuned on to the needed frequency by moving a ferrite rod along inside the inductor.

However it is not conveniently because the length of the tuned magnetic loop antenna may be vary in twice. Figure 2 shows a tuned magnetic loop antenna with constant length.

Ferrite core (item 1) of the antenna consists of two ferrite plates (in dimension (W x T x L ) 18x 2.5x 110- mm) that are divided by a thin insulator disk (item 2). When the plates are in one plane the antenna inductor has maximum inductance. When the plates are in cross position the inductor has minimum inductance.

 Figure 2 Tuned Magnetic Loop Antenna with Constant Length

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