Hi Kevin,
The W6NL Moxon is pretty simple (no matching components) and it is a 50 ohm
feed.
Check out:
http://www.k3lr.com/engineering/moxon/W6NL_Moxon104.pdf
The VSWR never gets over 1.4:1 from 7 to 7.3 MHz
73,
Tim K3LR
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Kevin Normoyle
Sent: Sunday, July 18, 2010 11:44 AM
To: TOWERTALK@contesting.com
Subject: Re: [TowerTalk] 50 ohm yagis (40M2L) ?
On 7/18/2010 8:18 AM, john@kk9a.com wrote:
> BTW, it is pretty easy to design a 2el
> yagi with 50 ohm impedance eliminating the need for the match.
>
> John KK9A
>
40M 2L 50 ohm impedance? with reasonable gain/f/b/swr bandwidth? I don't
think so, or I couldn't do it
(with my boom length and full length elements)
Am I missing something?
Actually I did create one by accident. If you off-center feed the DE,
you can get a 50 ohm match without too much loss in the other metrics.
I thought that was interesting. I saw someone proposed that elsewhere,
and it actually does work. It would be possible mechanically, but there
is a loss in gain.
Does anyone have a 40M 2L with 50 ohm input, with no matching
components? Well I guess a moxon does it, and maybe some dual-driven
things? what am I missing? I thought a simple 40M2L can't, as far as I
tried.
-kevin
ad6z
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