Why a high-frequency radio needs a ground plane and no VHF radio?
I wonder what a counterweight or balun is in the context of marine ecosystems of high frequency radio and why the board is required for HF radio equipment but is not required for VHF radios. Thanks
Scale. If scaled HF VHF antenna size, would work as well as VHF antenna does. But scale antennas means wavelengths. If VHF is ~ 300 MHz, we talking about a wavelength of 1 meter. If the IC is 30 MHz, which is a wavelength of 10 meters. This means that the extension of the HF VHF antenna size means multiply all lengths of 10, including height above the water. That's not really practical for IC. A common antenna is a vertical dipole. But instead of the dipole HF full, you can replace the bottom of the dipole with a plane and get almost as good performance. # Radio_antenna_theory http://en.wikipedia.org/wiki/Ground_plane wave, the extra half is not as big a problem, why sacrifice the gain of the antenna when not to? As to the question balun, which depends on the type of antenna, cable type, and source and destination of the signal. One balun converts the balanced signal (Ni landside) for unbalanced signals (one side is ground) http://en.wikipedia.org/wiki/Balun
WLO Radio on 17022.5kc CW
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