well, I THOUGHT I had a good ground.....16 radials I think, 1/4 long.....so I
thought I'd see around 30-35 ohms impedance.....not sure what to think
now.....I was going to get either a balun and unun at the feed point, was going
be someone else's statement that there inv l was around 22 ohms, glad I
measured mine before I ordered one....
----- Original Message -----
From: "F Z_Bruce" <k1fz@myfairpoint.net>
To: ww3s@zoominternet.net, "Topband" <topband@contesting.com>
Sent: Sunday, November 18, 2018 10:55:47 AM
Subject: Re: Topband: Impedance of inv l?
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 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
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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