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Old January 23rd 04, 01:14 AM
Richard Clark
 
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On Tue, 20 Jan 2004 20:19:39 GMT, "Jimmy"
wrote:

Is an antenna that is resonant on 10 meters still a 1/4 wavelength antenna
if it is physically only 4ft long


No.

or would this be an 1/8 wavelength
antenna(more or less)


Close enough to say Yes.

I am saying this should be called an 1/8 wl antenna
though I am arguing with those who generally know more more about this than
I. Not all the old timers disagree with me, so I am betting this is a pretty
common problem when discussing antennas.


Hi Jimmy,

If it wasn't before, it sure is now.

The description is the physical size in the applied frequency's
wavelength.

Skip all the sophistries based on resonance because at 10M that could
lead to a foot long loaded resistor being called a 107/4th's
wavelength antenna. (After the first couple of "electrical"
quarterwaves, why stop? Resonance certainly cannot tell which
quarterwave it is at.) The only way to distinguish successive, odd
quarterwavelength antennas is in their radiation resistance which
accumulates with SIZE, not components (unless you are stringing
resistors like christmas tree bulbs). Even then, the cumulative
resistance does not add beyond the 3rd or 5th quarter.

73's
Richard Clark, KB7QHC