Frankly I'm wondering more about the physdcal durability of the
antennas, if they weigh (as some have said) only about 2/3 as much as
the equivalent product from JK or Opti-beam. Thinner-walled tubing?
Anyway, that's why I asked about the RHR Maine site.
73, Pete N4ZR
Check out the new Reverse Beacon Network
web server at<http://beta.reversebeacon.net>.
For spots, please use your favorite
"retail" DX cluster.
On 10/21/2021 8:43 PM, Lux, Jim wrote:
On 10/21/21 2:20 PM, john@kk9a.com wrote:
I would like to put up an isotropic antenna and compare it to my Yagis.
Yes, you could power your measurement system with a perpetual motion
machine as well.
The Hairy Ball Theorem says that building an isotropic antenna is
impossible. (https://en.wikipedia.org/wiki/Hairy_ball_theorem )
Hence, you build a standard gain antenna, the gain of which is
calculate-able from dimensions and materials.
A dipole is easy, and fairly straightforward to calculate the gain
(including ohmic losses). As is a "short dipole".
Or, you build 3 antennas and do a three cornered hat.
The antenna range literature is full of practical solutions.
Free space gain measurements of large antennas is difficult. I have
seen some herculean efforts toward that end (promulgated by people who
should know better).
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