Jim wrote:
I need help in building an H type of tracking antenna for use around 166-167
mhz. This is for wildlife tracking. I have a couple of handheld 3 element
Yagi's that I built using YagiCad to do the math, and they work well, but
they are big and clunky.

There are times when I am willing to sacrifice the good f/b ratio of the
yagi for convienience, for instance when working in brushy woods. I have
used an H for tracking at 151 mhz, but of course, I can't use that one for
166.

I would think you could simply scale all the dimensions of your 151MHz H
down by a factor of 151/166.

For example, if the "crosspieces" of the 151MHz H are 39" long.. then
for a 166MHz H, they'd be 39*(151/166) = 35.5" long. You'd likewise
scale the distance between the two crosspieces.

Depending on how it's assembled (and whether you still need it for 151)
you could just cut down the 151 antenna.
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com