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Folks:

Roger is spot on with respect to misinformation offered on the Web,
supported by Dave W0LEV's frequent plea to be wary of unsupported wisdom
offered on YouTube.

Two real-life examples come to mind, with quotes from published e-mails:

In the first example, an internet "expert" advises that a full wave
horizontal loop antenna solution will offer the user a 6dB gain over a
dipole., or a signal that is 4X as powerful off the wire as a dipole.
I hope the guy reading the advice didn't really think his KW was going to
sound like 4 KW.

In the second example, the internet "expert" has decided that the
relationship between wavelength and frequency is 1 Lambda = 1005/f.
Wherever this guy is, the speed of light must be different than what it is
in the rest of the world - 983.571056 feet per second. If the author
"forged it himself" he copied the wrong figure.

*Example 1:*








*"Well in that case, the very best antenna (performance-wise) would be a
full-wave horizontal loop for 5 MHz.Unfortunately it is not small and not
inconspicuous. But it will have the best performance for the distance and
directions youwish to cover.The loop must be approximately 200 ft. long,
with 4 equal-sides of 50 ft.The exact length must be adjusted for your
exact frequency.The formula for calculating the overall length in ft. is
1005/f (where fis frequency in MHZ).This will work fine at a height of 20
to 30 ft, but requires 4 elevated supports.Alternative: you can build a
horizontal delta-loop. Sides about 67 ft.Either one of these will give you
about 6dB gain over a dipole."*

*Example 2:*










*"Subject: [Aerial-Talk] Velocity Factor SolvedI have a short explanation
and a long explanation.The short explanation is, all that crap is just
mental masturbation; creating work for the sake of having something to
do.In practice we use a formula, regardless of which one, cut the antenna
longer than necessary, then shorten to get resonance where we want. Most
important is that we have a stake in the ground and then cut it longer.The
Long Answer.1 Lambda = 1005/f? Lambda = 502.5/fThe vf of coper wire is
about 0.98; 0.98 × 502.5 = 492.45 (differs slightly, depending on whether
it is solid or stranded wire).If we put insulation on the copper wire, the
vf is about 0.96 to 0.97, depending on the type of insulation.0.96 × 502.5
= 482.4 (but we still haven't considered end effect).End Effect shortens it
another (about) 3%; 0.97 × 482.5 = 467.93 ... or 468.*
*Never believe a statistic unless you forge it yourself"*

One might just chuckle and move on, but the author actually worked for a
company that made antennas!

Owen will be missed, as will Roger and others like him, when they decide
they've done enough.

Sincerely,

Ed Mccann
AG6CX



On Mon, Jan 27, 2025 at 9:43?AM Roger Need via groups.io <sailtamarack=
[email protected]> wrote:

You can add my name to the long list of readers that will miss Owen
Duffy's blog. There is a lot of misinformation on the Web when it comes to
RF topics and many of his posts were a well written technical rebuttal to
many of these myths and falsehoods. His treatise of a given topic was
always backed up with facts, example calculations and graphics. His
online calculators were very useful and unfortunately no longer available.

Owen reads this group's messages and he had a particular interest in how
to get the most out of a NanoVNA. Many posts were about getting accurate
results and methods to achieve this. His other contributions were his
modifications and bug fixes to the NanoVNA app (which OneOfEleven donated
to the community). He also corresponded with DiSlord and suggested
improvements to the firmware which enhanced the NanoVNA feature set.

On a personal level we communicated several times via email and I enjoyed
the technical exchange. I appreciated his expertise and the mentoring
that he provided to me.

Publishing a blog that is technically accurate and has useful articles
takes considerable time and effort. There is also the financial cost
associated with keeping a domain name. I guess after many years he felt it
was time to move on to other interests. Owen you will be missed.

Roger Need in Canada