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Re: LF: Wire in the Air etc

To: [email protected]
Subject: Re: LF: Wire in the Air etc
From: "Mike Dennison" <[email protected]>
Date: Wed, 6 Jun 2001 12:21:22 +0100
In-reply-to: <[email protected]>
Reply-to: [email protected]
Sender: <[email protected]>
       About antenna .  I wonder if the increase in efficiancy is caused
by the higher antenna capacity which permits smaller coil and therefore
less loss due to coil resistance.  This might also explain the big
signals from  Jack and the OH station.  I am thinking of putting up a 50
ft vertical with a 400 ft long wire from top.   How does that sound?
      John VE1ZJ
You will only save an ohm or two on the loading coil, whereas there is much
more to be saved in the earth resistance. As with most amateur radio, the big
signals have lots of wire at a good height.

Your projected antenna would be the envy of most Eu operators, but if you
can get it higher - even at the expense of length - it will work better. ERP is a
function of effective height squared. The effective height is directly
proportional to actual height, but the relationship between actual and real
height is not affected much once you have a good size top section, so actual
height is the most important. Of course, as Laurie has demonstrated, it also
helps if you can increase the current significantly with a bigger top section, as
ERP is also a function of current squared.
Mike, G3XDV (IO91VT)
http://www.lf.thersgb.net



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