The personal attacks aren't really necessary. I try hard to make
sure what I say is accurate. The only reason I am involved in
reflectors is to learn or help others lean, not to insult people or be
> Where did I say anything about antenna elements?
> Thicker more lossy conductor (same material)?
> Tom is "right" even when he is wrong, I rest my case (again :-)
> Yuri, K3BU
Factually, a coaxial dipole is more lossy than a typical copper
dipole for a few reasons. One is the conductor is woven, and woven
conductors have significantly more loss than smooth conductors.
That why all the lowest loss transmission lines, for a given line
size, use smooth conductors in the current carrying areas.
Second, there is a poor dielectric coating the wire (the PVC
Jacket) at the area where the electric field ism most concentrated.
Third, coax makes a very low Q lossy stub. Q of a 1/4 wl RG-58
stub is only around 15-25.
If you take the time to read analysis of the coaxial dipole appearing
in QST and other ARRL publications, you will see they also agree
the bulk of the broadbanding by using a coaxial dipole is caused by
added loss, not by stub effects. You can find the efficiency
problems described on 9-4 of the 18th ARRL Antenna Handbook.
That is what I measured here, and what is commonly published by
many sources (like Walt Maxwell in Reflections).
73, Tom W8JI
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