I would do the same thing I have been doing for 30 years and the same thing
I have told you to do many times:
DO WHAT YOUR FRIEND SUGGESTS!
Go look at my Inverted-L picture again.
There is no difference in the theory between the Vertical and Inv.-L when it
comes to matching and efficiency.
I am doing EXACTLY that.
I make the antenna about 15% longer and shorten it electrically with a
capacitor.
This raises the feedpoint impedance to 50 Ohms (in the ideal case).
Unfortunately I made mine too long and it is at 73 Ohms, so my SWR is 1.5:1.
Your friend is SPOT-ON!
73
Rick
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Richards
Sent: Friday, November 08, 2013 9:18 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] 160 M antenna
Interesting commentary, Ken.
I DO have a 40m ground plan with 65 radials. And it has that textbook
38 ohm low SWR you mention. It seems to work swell... but your comment
suggests it could be better.
A friend suggested I make it slightly taller and add some capacitance until
it presents a an inherent 50 ohm load. (I think that is what he said...
let's assume HE said it right, if this is not a good idea... and presume I
remember it wrong...)
So - What would YOU do with my antenna to make it work better?
(This is NOT an argument - it is a very serious question to me.)
-------------------- K8JHR -----------------------
------ Original Message ------
From: "Ken Brown" <ken.d.brown@hawaiiantel.net>
A quarter wavelength vertical over an excellent ground counterpoise system
has an impedance of about 37 ohms. If you don't need a matching device to
get a 1:1 SWR at the resonant point, then it is likely you have about 13
ohms of loss resistance (the kind that produces heat, versus radiation
resistance, the kind that produces a radiated signal) that added to the 37
ohms of radiation resistance makes a perfect match to your 50 ohm coax. Very
convenient. Not very effective. What would you rather have? A low SWR or a
stronger signal? Many hams have chosen (perhaps unwittingly) a low SWR.
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