W0BTU Beverage receiving antennas (These are miscellaneous hodgepodge notes about Beverage antennas, from different posts I have made on qrz.com, eham.net, the Topband mailing list, and direct email. Someday I will organizine this and create a decent web page about Beverage receiving antennas.) I have two 2-wire, switchable bi-directional Beverage receiving antennas. Both are 580' long and are supported on 10' high posts 100' apart. I built them for 160 meters, but they work well from the low end of the broadcast band to 20 meters or more. There's some photos of my Beverages on my web site. Looking from the air, my Beverages cross like an X, covering NE (Europe, N. Africa) - SE (S. America, Caribbean, S. Africa) - SW (Australia and Oceania) - NW (Japan, AK). If you have the space, you should consider at least one. Even just a simple single-wire Beverage antenna. Mine are "magic" antennas! On a scale of one to ten, the "wow factor" is an 11. It has been said that Beverage antennas "want to work". In other words, their construction is not critical. If they are not exactly in a straight line, or if their height varies a little (such as if you have to cross a ravine, or go up and down a hill -- even a steep hill -- they will still work. For two-wire bi-directional Beverage antennas, the impedance of the two-wire line should equal the impedance of the two wires to ground. If they do not, then you need to change the ratio of the 1:1 reflection (far end) transformer. I used galvanized electric fence wire, and calculated the diameter (.061") vs. spacing (1.1") so that the feedline impedance was equal to the impedance between the feedline and ground at 10' high. If you construct your Beverage so that those two impedances are significantly different, then you should use a reflection transformer other than a 1:1 as I did. In your case, you are proposing to use 145 ohm line, which at 6 feet above ground has a common mode (both wires to ground) impedance of about 480 ohms. You would need to change the 1:1 transformer to about 3.33 to 1 for optimum performance (F/B ratio) of your Beverage. I fabricated my own open wire line out of plated steel electric fence wire, which is very strong. Using the known values of (1) the wire diameter and (2) the desired height above ground, I then made some plastic spacers with two holes 1.10" apart. This spacing made the common mode and differential mode (line) impedances nearly equal. The 580' bi-directional Beverage I made from this line works absolutely fantastic for receiving weak DX signals on 160 meters. They will also work on 80 and 40 meters, and occasionally on 30 and 20 meters as well. I sometimes play with them on the AM BC band. On some frequencies, I can hear four different AM radio stations on the same frequency as I switch among four different directions. Earl Cunningham, K6SE (SK) swore by galvanized elecric fence wire for Beverage antennas. He said copper was inferior, it did not produce the same F/B ratio. He once put up copper, but took it down and replaced with with galvanized electic fence wire. Sometimes losses are an advantage. One Beverage here has the switching arrangement with a single run of RG-6, but the other has no relays. Instead, there are two runs of flooded RG-6 running all the way to the operating postion. The relays and terminating resitors are there. I can turn a knob here in the shack and select any of four directions (SW, NW, NE, SE) that I want to listen towards. But maybe you ought to start with a simpler Beverage antenna design, and then you can try building something along the line of what I have. All you really need for a simple Beverage receiving antenna is a long single wire, 6 to 10 feet high, between 1/2 and one wavelength long (or more) at the lowest desired frequency, and pointed more or less in the direction you want to receive signals from. If you do a Google search for "beverage antenna", you will find a lot of information on them. Some of the info at http://www.w0btu.com/files/beverage/ might interest you, but a lot of that is just hodgepodge at present. Try http://www.google.com/#hl=en&source=hp&q=beverage+antenna. You'll need coax (any old coax) feeding the near end, a simple matching transformer, a termination resistor at the far end --pointed in the desired direction-- and grounds at both ends. We can help you with those details if you like. Possibly, I could even build the transformers for you. I suggest you Google "Beverage antennas". Where are you located? Unless you are located out west, you might try a Beverage pointed NE towards Europe. How long can you make yours? I have animals (deer) and falling limbs. The galvanized electric fence wire, 10' high, has never broken even when a very heavy limb fell from the top of a tree onto the end of one of them (see the Beverage photos). ----------------------------------- I once knew a ham who, during a local thunderstorm one Field Day night, used a BOG (Beverage On the Ground) antenna to receive for 75 phone. He could hear little on the low dipole he was using, but the coax on the ground really worked, according to him and others who were present. I cannot possibly imagine a BOG working any better than my BIA (Beverage In the Air) Seems like ON4UN has some info about the BOG in his great book. ------------------------------ 03-27-2010, W0BTU Originally Posted by KJ4TIR View Post ... I realize that talking on HF depends on a number of factors but in your experience, how far have you been able to reach someone on 160 meters? If you were in my posistion, the foothills of South Carolina, how far do you think I could reach? ... Adam, I've been on 160 since January 30, and I've worked 28 countries with a wire thrown over a tree (and two elevated radials). I listen using Beverage rx antennas. I've worked Australia and New Zealand, quite a distance from here. Others have done far better than me. -------------------------- There's some spreadsheets ... OpenWireZ(2).xls OpenWireZ.ods OpenWireZ.xls ... at http://www.w0btu.com/files/antenna/ that you might find useful for calculating both impedances. Excel or Open Document (Open Office) format. They were invaluable to me in designing the open wire line for my Beverage receiving antennas, so that I could use 1:1 reflection transformers. Those .ods spreadsheets should probably be moved to the beverages folder. You can open it with the free Open Office spreadsheet. ------------------------------ You could use the two-wire twisted pair for a bi-directional Beverage. See http://www.radio-ware.com/products/sv2bevsys.htm. ---------------------------- Wich is the best 160m antenna ? http://forums.qrz.com/showthread.php?t=260716&highlight=beverage -------------------------------------- external RX antenna overload: http://forums.qrz.com/showthread.php?t=266646&highlight=beverage ------------------------------------ 160 is the only band I currently operate, using CW around 1825. It's a great band, and it's not called the "Gentleman's Band" for nothing. You will find that a vertical with a good radial system will work well for DXing while using a separate RX antenna such as a Beverage or a K9AY loop. I should warn you about something, though. ;-) If you operate 160 meters much, you may get the Topband Disease. Perhaps I should now explain the symptoms of the disease. They are as follows: * Desire to be on the radio at sunrise. * Desire to be on the radio at sunset. * Desire to be on the radio at all times in between Sunset and Sunrise. * Desire to struggle for months to work a single station in a new country. In extreme cases, this might go on for more than a year. A good example is Riki, 4X4NJ in Israel who tried for two years to finish off working all the states in USA. * Never being satisfied with the antenna system and constantly trying new ones. * Only comes down to see the family after working a new country (to gloat). During the rare fantastic opening, will come down after each new country and hold up fingers indicating how many new countries were worked so far. ... * Drinks lots of water before going to bed with the sole purpose of waking up in the wee hours of the morning to see if a new country can be found. * Has problems getting to work on time during the winter months. * Sends equipment and wire to people in unworked countries, hoping that the end result will be their QSL card on the wall. * Spends thousand of dollars going to rare countries just so other people can work it. This is a problem, as they don't get credit for the country themselves!! If these symptoms persist for more than one sunspot cycle (every 11 years), then you should strongly suspect TopBand disease. More info at http://n6tr.jzap.com/tbdisease.html -------------------------------- W8JI: "A vertically polarized antenna with a good ground system will work much better than any horizontal antenna. An Inverted L is one of the best ways to make a good transmitting signal, so long as you have a good ground system. For receiving, a Beverage is simple and easy and very good. If you do not have the room for a beverage, then some small loops will help. Look at K9AY and Flag antennas. Since you cannot have much height, a dipole would be as good or better than an extended zepp or big horizontal loop. Nothing will be as good as an Inverted L or another good vertical for transmitting." ------------------------------------------ I do not ground the coax shields at the Beverage reflection transformer box, nor do I switch them. The only thing you need to ground at the feed end of your Beverages is the transformer secondary. ------------------------------- I also have an as-yet unsorted collection of Beverage antenna information on www.w0btu.com. Click on Files and then browse the Beverage folder. ----------------------------- Absolutely you should consider a 2-wire. Just make sure you use a reflection transformer as in http://www.ae5d.com/bev/bev5.png. That's exactly the way mine are wired and they work great. You can cross other beverages about 90 degrees to each other. Here's what I mean: http://picasaweb.google.com/katie657...79408328319170. They are only about 7 inches apart and do NOT interact. -------------------------------- If you haven't built the transformers yet, get some FB-73-202 binocular cores as in the 4th edition of ON4UN's book. I just changed one Beverage over to those today, and do they ever work great! :-) Of course, the fact that some of the old ones were zapped by lightning (just learned that today) didn't help. ----------------------------------------- Q: And finally, what are the negatives of the 2 wire vs individual single ones? A: I used 580' because W3LPL suggested it was an 'optimized' length. DX Engineering says 600'. It's not critical. I know that I read where W8JI said that it's a waste of wire going much over 500' for a single Beverage. But I read since then he uses some 800' or so long Beverages. The twisted pair is a different impedance, and could require different transformers. The negatives? Complexity (that could be argued against) and perhaps cost. And the open-wire stuff might not last as long as a single wire. That's about it. There is no appreciable difference between pattern and F/B ratio. I think the positives outweigh the "negatives". For 4 directions, only half the required amount of supports and real estate. ---------------------------------- A two-wire Beverage, like this one allows operation in either direction. On mine, there's a relay, two termination resistors, an RF choke, and a capacitor at the feed end, besides the two transformers. Look at http://picasaweb.google.com/katie657...77014482137426. Putting +12VDC on the coax switches one Beverage from SE to NW. Two Beverages cover 4 directions. Don't you think that's simpler? No extra control cable needed. -------------------------------- You can use the coax as a control cable if needed. That's what I do on one Beverage here to switch directions. Signal and DC on the coax, easily isolated with a couple of simple RF chokes and capacitors. You can see them in the photos of my Beverages. I can scan the schematic of the control box if you like. -------------------------------------- Quote: Originally Posted by KA0GKT View Post A beverage works best over poor ground, so I would think that running a return under the antenna may reduce the effectivness of the antenna by at least a little. A: You bet it will. There is a popular book on Beverages that suggests doing that, but just because something is in a book doesn't mean that it is technically sound. Quote: Rather than run a return line, consider a ground screen as opposed to relying on shortened ground rods. Alternatively, a rock drill could be used to make a hole in the granite into which to cement the ground rod(s) with hydraulic concrete. A few short radials at each end have proven to be effective. Works for me and lots of other happy Beverage owners. Check out http://www.w8ji.com/ground_resistance_measurements.htm. Also, the correct ratio transformers will help. -------------------------------- I've never tried one, but there is such a thing as a BOG, Beverage On the Ground. It's described in ON4UN's Low Band Dxing 4th edition. It's for LISTENING. Made from coax, there's a right way and a wrong way to build one. I'll stick with my 9'-10' high Beverages, though. :-) ------------------------------------------- When I put up my first 2-wire bi-directional Beverage (with different transformers than I use now), I occasionally had to 'help' the ground conductivity at the reflection transformer end. Although there were two copper ground rods and three radials, the only thing that made it work right from the feed end was to pour a hot, very concentrated solution of magnesium sulfate (Epsom salts) around the ground rods. That's no longer necessary, as I've made some changes. But it would be cheap and easy for you to try. Epsom salts are available at about any drug store or grocery store. --------------------------------------------------- I have found, like others, that it is unnecessary to terminate the unused cable. But I do anyway. :-) -------------------------------------------------------- I used galvanized electric fence wire, and calculated the diameter (.061") vs. spacing (1.1") so that the feedline impedance was equal to the impedance between the feedline and ground at 10' high. If you construct your Beverage so that those two impedances are significantly different, then you should use a reflection transformer other than a 1:1 as I did. ------------------------- From: Milt, N5IA Subject: Re: Topband: K3NA Loop Array To: "Nick Hall-Patch" , topband@contesting.com Date: Wednesday, June 23, 2010, 9:59 PM In the most simple explanation of the theory of operation of the Beverage antenna you must understand that the single wire above (or on) the ground is 1/2 of an unbalanced transmission line. The earth conductivity is the other "wire" in the transmission line. When the earth 1/2 of the "transmission line" becomes very conductive, the whole array approaches being an actual 2-wire transmission line (perfectly balanced). When that happens there is near ZERO signal received. The more unbalanced the line is, the more signal level is impressed on the wire which can be detected by proper impedance matching to a coaxial feedline going to your receiver. That is why the Beverage works well over poor earth. --------------------------------- An alternative to a Beverage is an array of short verticals, but the Beverage is the easiest to get working. ---------------------------------- Beverages should NOT be erected over metal fences. Why? A Beverage requires a poorly conductive ground (poor compared to the wire itself) under it to work right. http://lists.contesting.com/archives//html/Topband/1997-04/msg00080.html http://lists.contesting.com/archives/html/Topband/2010-11/msg00006.html ------------------------- > I recently built a two-wire switchable-direction beverage > based on the > description in ON4UN's Low-Band DXing (4th edition). [snip] > Currently, I am using two coax runs to > the shack but will eventually use a single coax that is > switched between the > low impedance sides of the two transformers. [snip] > I followed the schematic in ON4UN's book except for two > grounds which I omitted: > > 1) Figure 7-98A on page 7-70 shows two grounds on the far > end of the > beverage. One is the ground on winding n2 of the > transformer, which I > included in my beverage. However, the schematic shows a > second ground (to > the left of T5n1), which is connected to one of the two > beverage conductors. > What is the purpose of this ground? This is a typo, and that ground should not be there. The only ground at the right (far) end of the Beverage should be on the secondary of the reflection transformer (T5a, n2). It appears that this drawing was originally Fig. 7-23 on p. 7-22 of the 3rd edition of the same book. When it was modified for the 4th edition, there was a ground that should have been removed. I'm looking at both drawings, and it it's easy to see how such an oversight crept into the new edition. Nobody's perfect. > 2) Figure 7-98A also shows a grounded connection between > coax J2 and coax > J1. What is the purpose of this ground? Since I am using > separate windings > on my transformer, I don't think it makes sense to > connect these coax > grounds to the ground rod for T1n1. I agree. On my new 580' 2-wire Beverage here, I'm using a single coax, and the shield is only grounded at the station end. I'm using a relay at the feed end of the Beverage that selects the transformer (either T1 or T4) and switches the terminating resistors across the secondaries of the transformers, rather than the primaries as is usually done. Don't think it matters. ----------------------------- Who can verify that used motor oil will keep my Beverage antennas from accumulating ice? I know I read it somewhere. I was ready to coat them using a paint roller, but the ice never came. :-) ---------------------------------------------- You would appreciate the book by ON4UN, John Devoldere about low band dxing, even if you're not interested in working DX. Unless you want to work only stations very close to you, use a 1/4 wave vertical, an inverted L, or a T antenna with about 60 1/4 wave radials. Use Beverage antennas for receiving. -------------------------------- I think if you talk to the people who operate 160, you'll find out that few (if any) of them use a dipole on that band. Most are using verticals or inverted L antennas. They require a modest radial ground system of about 35 radials 50 feet long. And many use separate antennas for receiving; those with the room use Beverage antennas (or phased short verticals), and those with smaller lots use K9AY loops or similar antennas. That's probably an oversimplification, but unless the folks you want to talk to are fairly close, you do really need a low angle of radiation on that band. A dipole is fine on 80 meters on up, but on 160, that's usually not the case. ------------------------------