>From the official WWV site, the bottom element is a sloping skirt that also >serves as guy wires. Sort of like a discone with the disc replaced by a >vertical element, I guess.
"The top half of each antenna is a quarter-wavelength radiating element. The bottom half of each antenna consists of nine quarter-wavelength wires that connect to the center of the tower and slope downwards to the ground at a 45 degree angle. This sloping skirt functions as the lower half of the radiating system and also guys the antenna." https://www.nist.gov/pml/time-and-frequency-division/radio-stations/wwv wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Sep 10, 2018, at 11:41 AM, Jim Brown <[email protected]> wrote: > > On 9/9/2018 7:02 PM, Wes Stewart wrote: >> The WWV antennas are center-fed vertical dipoles. > > Thanks for the reminder about this -- I vaguely remember reading about their > antennas years ago. Question -- from the description, is the feedpoint > higher than a quarter wave above ground? A few years ago, I did an NEC > modeling study of HF verticals that showed that doing that improved the > vertical pattern and seemed to suggest that it reduced ground losses. Your > thoughts? > > The study is here. http://k9yc.com/VerticalHeight.pdf > > 73, Jim K9YC > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
