Does a vertical antenna need a balun?
Contrary to popular belief that only balanced dipoles or balanced antennas need baluns or common-mode isolating devices or systems, verticals and longwires also require “baluns” (more correctly called common-mode chokes or isolators for this application).
What is the gain of a vertical antenna?
In an ideal world, it is found that a five eighths wavelength vertical antenna could exhibit a gain of close to 4 dBd, i.e. 4 dB gain over a quarter wave vertical.
Why do vertical antennas need radials?
Radials contribute to the radiation efficiency of the entire vertical antenna system. The worse your ground conductivity, the more important your radial system becomes.
Why price out aluminum for a home brew portable HF antenna?
I decided to price out the aluminum for a home brew portable HF antenna. The cost savings was just enough to speed things along. I have never once built a home-brew aluminum antenna. Readers of this blog will attest to my affection for antennas made from locally available copper.
What is a 75/80m full-size self-duty quarter-wave vertical antenna?
In our latest installment on DX Engineering HF vertical antennas, we’ll be looking at the 75/80M Full-Size, Heavy-Duty Self-Supporting Quarter-Wave Vertical —a high-performance antenna featuring ultra-wide SWR bandwidth; impressive gain; and either a 3 inch or 4 inch OD base section.
What is the maximum length of a vertical antenna?
Ideally a vertical antenna should not be longer than 5/8 wavelength, or most of the radiated energy tends to fire up towards the sky.
What is the basis of the antenna?
The basis of the antenna is that it is NOT resonant on any of the desired frequencies. It is designed so that the impedance presented by the radiating element on wanted frequencies is close to the secondary impedance of the transformer for maximum energy transfer.