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The Beverage Antenna is a traveling wave antenna

Updated: Feb 5

The Beverage is a traveling wave antenna like the fast wave Rhombic, if it's not terminated it will be bi-directional, if it's terminated it will be directional and a true beverage.

A BOG (Beverage on the Ground) is not a Beverage, just laying out a couple hundred feet of wire out on the ground is not a beverage antenna, and it will not be very effective for many reasons. Laying a wire on the ground sounds very easy, but there are better solutions for receiving if that is all you're going to install. Single wire beverage antennas are low cost and low noise.

The inventor was Harold Beverage 1921. Harold told me at an IEEE meeting years ago, that his patent for the Beverage antenna needed to be 1 to 4 waves long for the lowest planned frequency, in fact he had one at a RCA site in NJ that was 9 miles long!

Most Hams don't know that a key concept with traveling-wave type antennas is that there are no standing waves on the antenna itself, which means that the current and voltage levels are the same everywhere along the antenna conductors. That type of antenna therefore has the distinct advantage of working over very wide frequency ranges. By using switches to change between antennas there is No waiting for a rotator to turn, just every direction, every band, every time, by selecting the proper antenna. The antenna wire and the ground under it together can be thought of as a "leaky" type of transmission-line which absorbs energy from the radio waves. The velocity of the current waves in the antenna is less than the light speed due to the ground. The velocity of the wavefront along the wire is also less than the speed of light due to its angle

The Beverage antenna uses "wave tilt" for its operation. At low HF frequencies, a vertically polarized RF wave traveling close to the surface of the earth with finite ground conductivity sustains a loss that causes the wavefront to "tilt over" at an angle. The E-Field is not perpendicular to the ground but at an angle, producing an electric field component parallel to the Earth's surface. If a horizontal wire is suspended close to the Earth and approximately parallel to the wave's direction, the E field generates an oscillating RF current wave traveling along the wire, propagating in the same direction as the wavefront. The RF currents traveling along the wire add in phase & amplitude throughout the length of the wire, producing maximum signal strength at the far end of the antenna where the feed-line is connected. Laying on the ground will probably not work will at all, and force you to add an additional pre-amps, but at 6" to a foot things come alive. Induced current and changing ground will definitely affect this antenna. These antennas are all about signal to noise, or Relative Directivity factor. RDF is the antenna gain in the forward direction divided by the gain in all other directions. It is also part of the signal to noise improvement factor (SNIF). The Beverage antenna actually receives less signal than an effective transmitting antenna. The goal of a Beverage antenna is to increas the signal-to-noise ratio (SNR) for better reception. The antenna should increase the signal level (without increasing the noise) or decrease the noise level more than the signal. I have had a number of 1500 foot beverages up over the years, at one time I had six 2 wire switchable antennas up. But remember, that Capture area or Effective Aperture is determined by antenna gain and the wavelength, not by the antennas physical wire size. The E Field is not perpendicular to the ground but at an angle, producing an electric field component parallel to the Earth's surface.

On 160 meters 400 to 800 feet long 4-6 dB RDF 100 degree beam-width

1000 to 1400 feet long 8-10 dB RDF 70 degree beam-width

+1500 feet long +12 dB RDF 50 to 60 degree beam-width

I started putting them at 3 foot high, but the deer always got them. So I hung them up about 10 foot and they would droop to about 6 foot high between supports, which I put up about every hundred feet. I drove steel T posts in the ground to about 4 foot and then put 2" PVC pipe 10 ft long over the top of them, it makes a great support. The 5-6 foot high antennas are not noticeably different than 10 foot high antennas on 160, but the lower ones are

noticeably better on 40 meters. Putting the antenna higher in the air, that would only increase the noise picked up.

They have to be run in straight lines, I find the shortest beverage that is really effective for me was at least 500 feet for 80 meters and 1000 foot for 160 meters, and those are elevated off the ground. Much shorter and you're probably wasting your time, if you don't have the space I would go with a small Magnetic loop, Flag, active vertical and others. Sure you can hear signals on shorter beverages but they're not really a true beverage, if they're much shorter than a one wavelength. You can stack 2 or more shorter ones, and the reception improves and the antenna pattern changes are small, I would start with 1/2λ or more for phased Beverages. You need to think about effective aperture or what hams call "capture area" it has to be large enough for the external noise to override receive system internal noise. Military telephone wire will definitely work, the resistance isn't really going to hurt you much on a traveling wave antenna, after all you plan on terminating them.

You may not want to waste your time if you can't get one or two wavelengths or phase two for directivity on your lowest band, there may be better solutions, like loops, Loop on the ground and others.

Too small of an effective aperture (short antenna) the internal noise starts to dominate the signal-to-noise. Effective Antenna Area, which can also be measured on antennas in the field, by comparison with known antennas. You should also read and understand Friis Equation or the Friis Transmission Formula.

I use a 9 to 1 balun for matching my antennas. Your terminating resistor needs to be a non inductive type resistor (very important). It doesn't have to have a very large value, since you're not transmitting on it, however expect them to burn up in lightning storms, where there's a ton of induced current or differential potential. You're dealing with a very long piece of wire. A standard variable resistor is not what you need, it has to be non-inductive, the value is not too critical somewhere between 300 and 600 ohms will work, it's not critical at all for receive.

The ground system mainly provides an RF and lightning ground. Having a very low ground-resistance is not especially important. The antenna needs a stable ground, not necessarily a low-resistance ground. If you are in an area that has large T-storms you can expect your 9 to 1 matching Network to be blown apart, so I currently use larger toroids and I haven't had any issues in the last few years. I use RG59 or RG6 cable TV coax and F Type connectors which is very cheap, and I have had runs of 500 feet or more to my main control boxes.

Baluns should have an inductive reactance that is 10 times the impedance. Using 50 ohm coax go for 500 ohms. The losses at the terminating resistor end of a Beverage have somewhat less effect on signal output than losses at the feed end of the wire.

A dual-wire variant is sometimes utilized for rearward null steering or for bidirectional switching.

I worked 200 countries on 160 meters and I would not have been able to do it without the beverage antennas. They are still my go-to antennas for use on my diversity receive setup for 160-40 meters.


More good reading, that someone sent me. They said it was maybe from V. Misek, W1WCR?

The secret to the Beverage antenna is that it works against a LOSSY GROUND. Not only will the Beverage not work in free space, but it won't work over a perfect ground, either!

When a vertically polarized wave travels in contact with the Earth, part of the wave is in free space (or nearly so, as air is essentially the same velocity factor as a vacuum), and part of it travels through DIRT, which has a significantly slower velocity factor. Since nature will not allow a discontinuous wavefront to exist, the wave MUST "lean" forward in the direction of propagation. This has two effects. The first is that the wave bends in the direction of the earth, allowing over the horizon propagation, even at low frequencies. The Second effect is that the leaning wavefront NOW has a very small electrical vector in the direction of longer at right angles to it. This VERY tiny vector, causes a small induction IN THE DIRECTION OF in the Beverage wire, which accumulates with distance traveled. SHORT Beverages are totally ineffective....but there is no theoretical limit to gain for very LONG Beverages.

Interestingly, HORIZONTALLY polarized signals CANNOT travel in contact with a dielectric....all TRUE ground waves are vertically polarized. But even if they COULD exist, the Beverage antenna would ABSOLUTELY reject such waves, because there will NOT be a "leaning" effect of the wave since BOTH sides of the wave are traveling through the same medium!

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