Tom .... I think everything is real quiet while a bunch of folks are busy
looking at manuals and crunching numbers with their analyzers. Someone
wants to find a mistake in your opinion.
Stand by.
----------------- Wes Attaway (N5WA) -------------------
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-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Tom W8JI
Sent: Monday, September 10, 2012 8:29 PM
To: topband@contesting.com
Subject: Re: Topband: electrical wavelength
> Run the numbers and for RG-6 we see that sq root of L/C is good above a
> couple hundred kHz.
>
> Dave WX7G
I just ran it in MathCAD and it showed a Zo and Vf slope starting down
around 150 kHz, but I assumed the conductors were solid copper. Conductors
have to be in the thousands of a inch range thick to cause an HF slope,
because skin depth is .00256 inches on 1 MHz for copper.
I cannot understand the HF and higher numbers at all, where it is all pretty
much set by the dielectric constant slowing the TEM wave.
I don't even think it would be a practical concern down to 100 kHz or so
where copper skin depth is .0081 inches and we might be getting into the
steel core, or am I missing something here? :-)
73 Tom
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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