Strange how hams like to name antennas. And strange how many hams are
stuck on the notion that if it is a nice 50 ohm load it is a good antenna.
A German ham (he's on the Ten-Tec reflector or the Eagle reflector), DJ5IL,
has pattended a "Shortened End-Fed Dipole".
If it is end fed, then it is NOT a dipole! It might use one end of the
dipole as a feed line, and feed it near the center and then be a dipole.
In that case it is not end fed.
This is significant, because:
* It needs NO RADIALS
* Being a half wavelength long (electrically), it is completely ground
independent. You won't have ground losses due to not enough radials.
*
Sorry this is a fantasy. Any antenna near the ground (meaning within a
wavelength or so) will induce some currents in the ground, and have
ground losses. If the high current portion of the antenna is less than a
quarter wavelength above ground the ground losses are probably
significant, unless the ground is a salt marsh or a good radial field.
Sure you can make a vertical with no radials, that has a low SWR when
fed with 50 ohm (or other) coax. Low SWR does not necessarily mean low
loss.
DE N6KB
|