Topband: WWV Antennas

[Terry Conboy]

At 06:20 PM 2008-03-10, Garry WR4R wrote:
>I wonder why the antennas at WWV are using ground planes with 9 radials?
>Nine just seems like an odd number and I wondered if there was a reason for
>this number as I don't see any explanation on their website.

In addition to the 9 drooping elevated radials, there are 120 radials 
on the ground, each 0.412 wavelengths long.

See Fig. 11 on page 16 of http://tf.nist.gov/general/pdf/1420.pdf for details.
A description of the antenna design starts on page 11.

73, Terry N6RY