Umm...
1. See the smiley.
2. 90 dB? Mathematically achievable. But...
2a. Does the design have margin? Can you move or change the wires more than
a tiny amount without seeing this miraculous notch disappear? If so, you
have design margin. If not, you have a modeling anomaly.
2b. Can you build this antenna in the real world and measure 90+ dB of f/b?
If you can, you have some very nice, expensive instruments. Or maybe broken
ones. And you have an astounding antenna. 90 dB is a 1,000,000,000 X
difference in signal strength. I'm guessing a lot of dummy loads are less
than 90 dB down from a dipole.
An interesting side note:
The current Novice question pool has a question something like:
Q: An SWR of 1:1 means ____.
One of the distracter answers is "Your SWR meter is broken." I about split
a gut laughing over that one! If I were the examiner, I'd give full credit
for this answer. :-)
73, Dave "the skeptical" N6NZ
-----Original Message-----
From: K7GCO@aol.com [mailto:K7GCO@aol.com]
Sent: Thursday, October 21, 1999 12:39 AM
To: david.b.curtis@intel.com
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] Re: 90 + DB f/b
In a message dated 20.10.99 10:34:10 Pacific Daylight Time,
david.b.curtis@intel.com writes:
<<
I think you should file a bug report with the software author :-)
73, Dave N6NZ >>
Dave
Every antenna I have built from Eznec modeling has checked out
perfectly
for pattern and feedpoint Z. No Modeling Black Flag has ever been needed.
If you are having trouble have someone check your procedures.
K7GCO
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