In the last summer I experimented and hung up of the antenna behind my balcony at 1.5 meters from a wall. I have received a significant improvement of the work of the antenna The antenna does very good operation in the ether, better than others indoors antennas. It gives low industrial noise and kills all TVI.

Reference:

I. Grigorov. Antennas for radio amateurs. - Majkop, 1998.

http://www.cqham.ru/

As it is seen, the "umbrella" top load (Figure 1e) gives the most effect on the resonance of a vertical antenna. For example, if to use an umbrella load for a vertical antenna in five meters height, the antenna quarter wave fundamental resonance wavelength would be changed from 20 to 50 meters!

Reference:

1.     Polyakov V. Technique of radio: Simple AM receivers.- Moscow, DMK-Press, 2001.

73! I.G.

http://www.antentop.org/

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