Jimmy wrote:
Several years ago some friends and I tried mking some gain measurements on
quads. Found that more than about six elements did not help the gain of
the
antenna to any useful degree.


This tends to give me doubts about the ethics of those who manufactor
the long quads.


I'm sorry that you and your friends weren't successful... but that
doesn't prove it can't be done.

Microwave operators regularly use long quads (loop yagis) with 20, 30
and even more elements. Range measurements *prove* that they work, about
the same as conventional yagis of the same boom length, but the loop
elements do have some constructional advantages for the low microwave
bands.

As with any yagi-type antenna, you need to add significant numbers of
extra elements and boom length in order to see a significant increase in
gain. If you do it right, the gain will come.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek