beverage antennas


here is some more information on beverage antennas w8ji thanx

beverage antennas link


My History With Beverages

I originally began experimenting with long, low, wire antennas in the 1960's. Even though I had a working mostly homebrew station, I now realize I had only a small idea what I was doing, and almost no understanding of what made antennas work.

My entry into Ham radio was from modified broadcast radios, and the very active 160-meter mobile group in Toledo, Ohio. I always thought the longer the antenna, the better the "pickup". was fascinated by the distant AM broadcast, lower shortwave, and 160-meter signals heard with long antennas. My early antennas were nothing more than hundreds or thousands of feet of very thin magnet wire, strung over tree limbs and along telephone poles (which had steel climbing pegs), all through a typical crowded 1950's suburban neighborhood. Unfortunately my early experiments were hampered by lack of room. Thin magnet wire, unwound from early-radio speaker field magnets, strung in the middle of the night through a crowded suburban neighborhood across neighbor's small lots, doesn't stay up long.

In the early 1970's, I moved to a house with several acres of woods. The soil was a very wet, sandy, black loam. A neighbor just north of me, W8FPU (Parker) was actually working a couple of VK's on 160-meters, something very rare at the time. Using information from a series of engineering lectures by John "Jack" Kuecken (now SK) and correspondence with Stew W1BB, I installed my first "real" Beverage antenna. I was delighted to find a large improvement in weak-signal reception from very simple, inexpensive, easy-to-install wire antennas. Eventually, that system evolved from a few long single wires to a two-wire reversible system. The two-wire system used two Beverages, oriented 90 degrees from each other. This gave four direction coverage. That system, with the addition of an in-phase and out-of-phase combiner, evolved into a forced-null system using just two reversible antennas. This was before binocular cores were available, and ferrite beads were just appearing. At the early date, I used a series of 73-mix beads to make my transformers, even publishing a few articles in small newsletters.

I continued to improve or refine my Beverage antennas over the years. Virtually all of my Beverage antennas now are arrays of multiple Beverages, not just single wires. While my large circle arrays of verticals, or broadside endfire arrays of verticals, are about even with two long phased Beverages, the Beverage arrays are simpler systems. Arrays of broadside Beverages remain my primary DX receiving antennas for the lowest bands. There isn't any other receiving antenna that is as simple, as easy to construct and maintain, and as foolproof as a Beverage! The only significant Beverage disadvantage is the long physical length required, and maintenance of a very long antenna. If we want significant directivity, Beverages (like all long wire arrays) require a great deal of space .

Testing and Comparing Antennas

I work a little different than many or most people when experimenting, always A-B testing and comparing antennas over time. This is partly because a newer, bigger, or better looking antenna always feels better. Even before something is used, especially if the "something new" involved effort or expense, we can "like" it and become emotionally invested in it. We want something new to work better, so we look for everything "good".

I credit a 7th and 8th grade science teacher for educating students about this phenomena. Early in school, a science teacher at Olney middle school in Northwood, Ohio demonstrated how easily and often false conclusions are reached, based on feelings about results or past performance memory. One year of science with Mr. Kohler, when I was 12 or 13 years old, changed how I look at many things in life. Because of Mr. Kohler, I almost always retain a reference or control, try to use direct measurements of what I actually want to know, and use multiple methods when possible. Mr. Kohler demonstrated how easy it was to reach false conclusions, unless we use valid measurements.

Most antenna myths and misconceptions, many making it into print in articles, come from repeating feelings or unsubstantiated claims, or are based on improper measurements or models. I've seen comparisons years apart, going on memory of how signals were on some other antenna that was long gone!

I presently have a great deal of room, with wiring in place to install multiple antennas, and reasonably good test equipment. This allows installation of multiple antenna systems at the same time, which allows direct comparisons over time, as well as measurements. I constantly refine antenna systems by comparing systems against each other for extended periods of time, usually more than a year.

there are more pictures and documents please go to link above



Popular Posts