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Re: Topband: Impedance of inv l?

To: topband@contesting.com
Subject: Re: Topband: Impedance of inv l?
From: Wes Stewart <wes_n7ws@triconet.org>
Date: Sun, 18 Nov 2018 12:31:38 -0700
List-post: <mailto:topband@contesting.com>
That also drives up the current in the horizontal wire with attendant increased horizontal radiation.

I chose for a couple of reason to do the opposite; shorten the wire to make the feedpoint capacitive and use a shunt inductor to get a 50-ohm match.  This really doesn't improve the 2:1 VSWR, that I consider acceptable, however.

Wes  N7WS

On 11/18/2018 8:55 AM, F Z_Bruce wrote:
That sounds about right. As you put a good ground system under it, that value 
will come down, and the efficiency will come up.

Many add extra antenna wire that pushes the current up the wire, this also 
raises&nbsp; the impedance, hopefully to near 50 ohms with the right length.
A capacitor (variable, then fixed) in series at the feed point can cancel the 
added inductance.

73
Bruce-k1fz
https://www.qsl.net/k1fz/beverage_antenna.html

&nbsp;
On Sun, 18 Nov 2018 10:41:36 -0500, WW3S wrote:

What should the Z be for a 1/4 wave inv l, with the radials attached to a 
radial plate? Mine seems to be 60 ohms or so....

Sent from my iPad
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