Considering shortened elements and the wide band required from 7 to 7.3, a
driven and reflector has three advantages.
The Rr is higher thus loading losses are a bit less critical, the antenna Q
is less, and a director parasitic element at 7 Mhz doesn't reverse as a
director in the high edge of the band.
Correctly building coils to minimize losses and placing loading devices
where it's most proper, there is not an advantage or a disadvantage using
them instead of linear loading.
In the other hand, often a linear loading system is easy and practical to
build and easily withstand power.
73,
Mauri I4JMY
----- Original Message -----
From: "Peter Sundberg" <sm2cew@telia.com>
To: <towertalk@contesting.com>
Sent: Saturday, May 12, 2001 5:36 PM
Subject: [TowerTalk] 40 mtr yagi
> A couple of questions for the group;
>
> What is better when building a 2 el yagi for 40 with shortened elements,
> driven + director or driven + reflector ?
>
> Linear loading is easy to accomplish, but does large diameter loading
coils
> out on the elements give better perfomance ?
>
> /Peter SM2CEW
> www.qsl.net/sm2cew
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