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VK3XL · May 30th 06, 10:35 AM

Quote:

Originally Posted by Sal M. Onella

"VK3XL" wrote in message
...[color=blue]

Hi all, I am currently building a new 2 meter beam for SSB. I am using
the DL6WU design on a 6 meter boom. While working on the antenna last
night a thought struck me "why not interlace a 70 cm beam on the same
boom"?
"snip"
Some help: I saw one for sale at HRO a few years ago. Might have been this
one:

http://www.eham.net/reviews/detail/3297

Note also that many VHF TV antennas are this way; the low-band elements for
55 - 88 MHz share the boom with the high band elements for 172 - 216 MHz.

These two bands are approximately in a 1 : 3 ratio, as are 2M & 70cm.

Thanks for the reply. All very interesting, but I am thinking of something a bit bigger ie 12 elements on 2 meters on a 6 meter long boom and up to 27 elements on 70 cm on the same boom. I fear that because 70 cm is almost exactly the 3 rd harmonic of 2 that the 2meter elements will act as unwanted directors in the 70 cm beam, any thoughts welcome.....
Mike
VK3XL