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Old 7th Oct 2013, 2:36 am   #52
ntscuser
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Join Date: Mar 2013
Location: Coventry, West Midlands, UK.
Posts: 279
Default Re: 405-Line VHF Aerials in 2013

Quote:
Originally Posted by Fezziwig View Post
Shades of the Jay-Beam Multibeam (think it was was) for UHF. J-Beam claimed high gain figures but tests showed them to be very poor.
Ours was certainly a poor performer. I think J-Beam's claim to fame was the 'skeleton slot' (as they called it) or 'trifold' (as others call it) active element and reflector? This necessitated the use of a helical balun transformer to match the very high impedance.

The only advantage of a Band-I X-array over an "H" that I can see is mechanical strength at the attachment point and reduced wind resistance.

It has to be said that a skinflnt uncle used a Band-I X-array for many years to receive not only Band-I but also Band-III transmissions from Sutton Coldfield about twenty miles away. There was no noticeable degradation in picture compared to our H+5-element yagi aerial mounted on a three-strorey chimney!
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