"Jeff Liebermann" wrote in message
...
On Fri, 15 Feb 2013 23:31:52 -0800, "Sal" salmonella@food
poisoning.org wrote:

I'm building a yagi from the measurement tables the ARRL Antenna Book.

Which Antenna Book and which yagi?

snip

Jeff, I have the 18th Edition of the ARRL Antenna Book, copyright 1997.

I'm in Chapter 18, titled "VHF and UHF Antenna Systems." I'm using Table
16, titled "Dimensions for 16-element 3.9-wavelength 222-MHz Yagi."

I'm bugged by something else I'm seeing. Table 16 specifies a 664 mm driven
element (DE) It's longer than the DE of other construction articles. Most
articles call for something between 645 and 648 mm. (Example: On the same
page as Table 16, I see also Table 14, "Free-Space Dimensions for the
222-MHz Yagi Family." It gives a DE of 647 mm.)

Something is indisputably okay. My prototype DE (664 mm) is hanging by
strings above my bench and I'm getting a 1.2:1 - 1.3:1 with a short length
of cable. I can hit a repeater 15 miles away with one watt without even
turning my DE vertical. Too bad neither of my analyzers works at 222.

Yes, I fully expect the match to need adjusting after I add parasitic
elements. The road from here-to-there has so many branches!

"Sal"