General Antenna
Posted on September 14, 2011
The title “General Antenna” refers to the fact that I am not right now concerned with 3-meter antennas, but with general antenna performance.
The title “General Antenna” refers to the fact that I am not right now concerned with 3-meter antennas, but with general antenna performance.
Over on the Big Talker thread(part 15 on shortwave) I said that today I changed the dipole antenna and had radically different results. Let me explain a few ongoing confusions.
WHEREAS most antenna books tell us to cut the length of an antenna to specific measurements, i.e., half wavelength, I found something different in a book by Edward M. Noll, W3FQJ, “73 DIPOLE AND LONG WIRE ANTENNAS,” where he writes, “Physical length is shorter than calculated wavelength by about 5%.”
Wow. 5-percent is a lot. Shorter.
AND another discrepancy has been noticed where some writers say the transmission-line should be a multiple of the wavelength, but another writer says the transmission-line should be an odd multiple of the wavelength.
Please close the gap on these seemingly different sets of instruction for calculating antennas. What say you?
