You guys keep talking about coax-fed antennas. Yes, although it may be easy to wind coax around a toroid and put it up at the antenna midpoint, that's not so easy with open-wire line. This discussion was very coax-centric and I wanted to open your minds that not everybody feeds their antenna with coax.
Balanced feedlines ("window line" or "open-wire" line) can have significant common-mode current. They're not immune to the effect. (I know you know this; I'm saying it for the benefit of all.) A device with high common-mode impedance, located right at the output of the tuner, suppresses common-mode current on a (balanced) feedline. That's it's purpose. I'm in agreement with you about the 1/ cause of common-mode current and the 2/ cure for it. I'm simply saying that for convenience's sake, consider putting the choke at the tuner output. A choke with high Z to common-mode current, external to the tuner, in a non-conductive box, with as short a connection to the tuner as possible, does quite well at suppressing common-mode current. I'll be happy to share my measurements with you. There is no coax anywhere in my antenna system. So my solution was to put a choke with high impedance to common-mode current right at the output of my antenna tuner. I encourage users of open-wire line to do that. Al W6LX >>> In all cases of a radiator fed with coax, ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com