I did a simulation with EZNEC. Took less than 15 minutes.
10 wavelengths and beyond was far field. At 5 wavelengths,
the signal strength was 15% higher than far field. At 2.5
wavelengths it was 100% higher.
This was for a 4 square transmitting array and a movable
receiving vertical.
73
Rick N6RK
On 9/5/2021 3:29 PM, Gary wrote:
Maybe an EZNEC grandmaster could do it in 10 minutes, but for the beginner
nothing can be done with any NEC program in 10 minutes.
73,
Joe kk0sd
-----Original Message-----
From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of Richard (Rick)
Karlquist
Sent: Sunday, September 5, 2021 2:36 PM
To: TowerTalk@contesting.com
Subject: Re: [TowerTalk] Field Strength comparison
Instead of using rules of thumb from ancient history, you can get a far more
precise answer by simply modeling the antennas under test and the test source
on EZNEC. Should take 10 minutes or less. If you can't go far enough to get
into the far field, you will at least know the correction factor at the
distance you can do. The modeling results also provide a sanity check on your
actual measurement.
73
Rick N6RK
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