The
Ferrite Magnetic Loop Antenna works fine at places with heavy
reflected signals-near TV transmitters. It allows get clear reception.
Antenna made on a ferrite rod with permeability 600. Such ferrite
rod use to for internal LW- MW antennas in transistor radio. Antenna
has band- pass not less the 8- MHz because of the losses in the
ferrite on the TV- Frequencies. Figure 1 shows the schematic of the antenna. Left
design is for one- band antenna and right design is for two- band
antenna. Inductor L1 is a coupling loop with TV. It contains 2
turns, with gap between turns 7- mm. Inductors L2 and L3 are tuned
on to working TV- Band. The inductor should have 4- 5 turns (length
11- mm) for 1- 2 TV Channels, 3- 4 turns (length 10- mm) for 3-
TV- Channel, 2 turns for 4- TV- Channel, 1- 2 turns for 5- TV-
Channel. The antenna would work well for FM- reception when would
be tuned to the FM- frequencies. Trimmer capacitors C1 and C2
have 6... 25- pF.
Figure 2 shows design of the
antenna.
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Radio #
7, 1960
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