Post by Admin on Feb 23, 2013 21:09:06 GMT
In the latest "Mission Critical" communications magazine there is a short article about the EH Antenna for HF operation.
Looks like the EH antenna has changed a bit since the last time I read about them.
These are very short dipole antennas that boast 87% efficiency. The HF antenna featured is for 3.5 to 8 mHz and only 4 feet long.
Most shun these as a hoax but the Ham operators have been making them work. The original write-ups were very involved regarding phasing and tuning. This newer design looks fairly simple.
From the pictures its basically a wire cage type of design that is enlarged in diameter at each end. It has a center loading coil in series with the two halves of the dipole which is link fed. Coax is used for the transmission line. Since it is a dipole it does not require radials.
They state that it can be mounted within two feet of ground zero although higher is better. When mounted 1/8 wavelength above ground they claim it performs as well as a ground mounted 1/4 wave monopole with ground radials.
Looks like the EH antenna has changed a bit since the last time I read about them.
These are very short dipole antennas that boast 87% efficiency. The HF antenna featured is for 3.5 to 8 mHz and only 4 feet long.
Most shun these as a hoax but the Ham operators have been making them work. The original write-ups were very involved regarding phasing and tuning. This newer design looks fairly simple.
From the pictures its basically a wire cage type of design that is enlarged in diameter at each end. It has a center loading coil in series with the two halves of the dipole which is link fed. Coax is used for the transmission line. Since it is a dipole it does not require radials.
They state that it can be mounted within two feet of ground zero although higher is better. When mounted 1/8 wavelength above ground they claim it performs as well as a ground mounted 1/4 wave monopole with ground radials.
