Hi Steve Steve Attfield wrote:

when doing a phase line for a crossed yagi to give it a circular polarization. how do you make sure that you have electrically 1/4 wavelength of line? it strikes me that this would greatly matter or else the antenna wouldn't be fully circularly polarized.

I would say that it's as simple as multiplying the actual wavelength of the frequency you are making the antenna for, with the velocity factor of the cable. It's the length of the braid on the cable that's important.

More info on cross-phasing of yagis can be found on DK7ZB, Martin Steyer's homepage at http://dk7zb.fox28.de Direct link: http://dk7zb.fox28.de/Cross-Yagi/crossyagi.htm

Good luck OZ1TMM, Martin