On Sun, 23 Apr 2006 09:57:09 +0100, Ian White GM3SEK
wrote:


If anyone wants to try a modern correlation, there's lots of data in
the VE7BQH collection:
http://www.ifwtech.co.uk/g3sek/diy-yagi/ve7bqh.htm

VE7BQH's data are all for yagis that might be useful for VHF/UHF
moonbounce, so boom lengths start at 1.8wl and range up to 8wl. (This
turns out to be no use to Reg - see later - but it's an interesting
topic in its own right.)

If anyone is interested in doing it, use the L(WL) and GAIN(dBd)
columns. With Excel, it should take all of ten minutes to get the data
from the web page and into a "scatter X-Y" graph.


Ian, I have plotted the data in VE7BQH's table, along with a
polynomial (1) curve fit and also the function given by K0TAR for
comparison.

The plot is at http://www.vk1od.net/lost/VE7BQHYagiGain.htm .

It would be dangerous to assume the fit function applies much below
the limits plotted.

Owen
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