[TowerTalk] Gizmotchy's

[Michael Keane K1MK]

On 4/9/2009 11:13 AM, Sain'T Tom wrote:
 > Is there any advantage in using the Gizmotchy configuration?

Not really.

Mechanically the configuration represents a 50% increase in wind area 
(and an  significant increase in weight) over simply tilting a 
conventional yagi design at 45 degrees to the horizontal

Is tilting an antenna 45 degrees to the horizontal an advantage? 
Probably not. One would gain a certain degree of polarization diversity 
that would help to fill in those fades that are due to polarization 
(Farady) rotation in the ionosphere. But not all fading at HF is due to 
Faraday rotation.

Om the other hand, because of the way horizontal and vertical 
polarizations reflect, the vertically polarized component doesn't 
receive the nominally +6dB from ground reflection gain at low angles 
that the horizontal component does. Mechanical reasons aside, this is 
the reason why HF yagis are almost universally horizontally polarized.

73,
Mike K1MK