Topband: Shunt fed T

[John G3PQA]

From: "john" <jb at beaumonts.karoo.co.uk>

> Could anyone advise me about top loading when 4 wires are use as an 
> alternative to 2 with this type of antenna. My present antenna is 82ft 
> vertical with 4 top lading wires each 35ft long,  I have been told only 1 
> wires counts as the loading/lengthening on this type of antenna which I 
> dont fully agree/understand. Is it not that a 2 wire tee you calculate the 
> missing portion of your vertical lets say I needed 127 ft for 1.83mhz and 
> my vert is 82ft so 45ft too short, so lets say 60% of 45ft = 27ft I would 
> need 2 top wires 27ft or maybe 70% of 45ft = 2 x  31.5 ft.


According to EZNEC a tophat of 4 x 35ft wires gives resonance on about 
1.6MHz , assuming single wire vert.
If the wires are shortened to 22ft resonance is 1830kHz
John 
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