++++++++++++++++++++ Date: Tue, 30 Oct 2001 10:04:28 -0000 From: "Paul Barlow" Subject: [Elecraft] 44' Doublet Dear all, only my 2p worth, but I have a 44' doublet in a bag ready to go up soon. If you don't have an ATU with a balanced output you can use a choke balun. Much happier with mismatches than the voltage transformer type and very easy to build. The W2DU type is described in the ARRL handbook, and the bits are available as a "guts" kit from the Wireman (www.wireman.com) for only a few $$. I used a choke balun with a large loop and Z11 very satisfactorily. I have been a "lurker" on the list for a while, and I ordered my K2 yesterday (hooray). 72/73 Paul M0CDP GQRP 10289 Fists 5579 ++++++++++++++++++ Date: Tue, 30 Oct 2001 08:26:04 -0600 From: fkamp at home.com Subject: Re: [Elecraft] 44' Doublet I suspect you guys might be dissapointed in a 44' doublet's performance if you do not use an antenna tuner. It is not a matter resonance but impedance matching. Match the impedance and you get the maximum amount of power tranferred to the antenna. That works on receive as well as transmit. So, if you don't have an antenna tuner, get one. Or make one. They are trivial in cost and effort for QRP power levels. I use a 44 foot doublet as well as an 88 foot doublet but only with an antennna tuner. Frank Kamp K5DKZ +++++++++++++++++++++ Date: Tue, 30 Oct 2001 06:46:07 -0800 From: Phil Wheeler Subject: Re: [Elecraft] 44' Doublet fkamp at home.com wrote: > > I suspect you guys might be dissapointed in a 44' doublet's performance > if you do not use an antenna tuner. His transmitter might be disappointed, too :-; But I think the original poster mentioned he wanted something to use with his K1 with KAT1. So, as long as he feeds it with a balun, he should be happy with that antenna for 40-10. 73, Phil +++++++++++++++++++++ Date: Tue, 30 Oct 2001 08:14:23 -0700 From: "Bruzenak George" Subject: Re: [Elecraft] 44' Doublet Phil is correct. I have the KAT1 installed and even with that I will be trying either a 1:1 choke balun or a 4:1 current balun with the 44' doublet. I'll let the list know when/if/how it works. Then, when I get my 4-band filter board built --- we'll see if I can make any decent QRP contacts. My current 51' G5RV is sorely lacking any performance on 30meters. My Kenwood TS570 can't even make it well. 73 de George K0CNT FISTS 8506 FP 369 ++++++++++++++++++++++ Date: Tue, 30 Oct 2001 09:21:44 -0800 From: "John Moriarity" Subject: Re: [Elecraft] 44' Doublet - ----- Original Message ----- From: "Phil Wheeler" > His transmitter might be disappointed, too :-; But I think the original > poster mentioned he wanted something to use with his K1 with KAT1. So, > as long as he feeds it with a balun, he should be happy with that > antenna for 40-10. And don't be afraid to try it *without* a balun! I know, a balun is the *right* way (I'm an E.E.), but I've been using a 54 foot inverted-V fed with window line, connected *directly* to my K2/KAT2 for six months, with excellent results. Maybe I'll get around to trying a balun someday ;-) 72, John, K6QQ +++++++++++++++++ Date: Tue, 30 Oct 2001 18:50:10 -0000 From: "Dave Johnson" Subject: Re: [Elecraft] Another Antenna Question George K0CNT, wrote asking about ladder line antennas and the K1 ATU. George (and others), from the diagram of the K1 ATU it appears to have less combinations than the K2 ATU. I have neither, but my Z-11 ATU is a similar design to the K2 ATU and tunes my 100 foot top, open wire line, doublet on all bands from 80m to 10m. On 80m it's a little touchy and sometimes needs a nudge of the "up/down" capacitance and inductance switches to obtain a better than 2:1 SWR, on the other bands it's fine. I've worked 68 countries using the K2 since March this year on this antenna, including JA on 40m. The antenna is in inverted V with the apex at 30 feet. The ladder line fed doublets work well over a reasonable number of bands, mine is "short" for 80m operation and is a little awkward to tune as a result. On bands above 20m the radiation tends to fire off in odd directions so the performance can sometimes be poorer than a dipole depending on direction. I feed mine via a 4:1 ferrite balun on the outside wall of the shack, there's a hole drilled straight through the brick wall with around 3 feet of RG-58 coax to the ATU. By keeping the ladder line fairly tight you reduce the number of spreaders needed and minimise the risk of wires fracturing due to constant movement in the wind. I use 1mm cross section, 6 amp insulated hook-up wire. Try one, they are simple and if it's too difficult to tune on one band, adjust the length of the top section and try again. Several people use doublets of various lengths, just try one you have little to loose. 73's Dave, G4AON K2 #1892, KIO2, KSB2, KBT2 and LDG Z-11 +++++++++++++++++++++ Date: Tue, 30 Oct 2001 15:19:20 -0600 From: "Stuart Rohre" Subject: Re: [Elecraft] 44' Doublet George, Even a full size G5 does not do well on 30m. The impedance is so high there, and I imagine the length of antenna also makes a very lobed pattern that does not have a lot of power in favored directions. 73, Stuart K5KVH ++++++++++++++++++++++ Date: Tue, 30 Oct 2001 16:29:36 EST From: JohnK1JD at aol.com Subject: Re: [Elecraft] 44' Doublet Running A/B tests here, a 30m dipole is multiple s-units better than a 105' G5RV. 73, John, K1JD Jamestown, RI K2's #139 & #583 ++++++++++++++++++++++= Date: Tue, 30 Oct 2001 13:49:11 -0800 From: "Ron D' Eau Claire" Subject: RE: [Elecraft] Another Antenna Question Dave, G4AON wrote about doublet antennas fed with open wire line: "On bands above 20m the radiation tends to fire off in odd directions so the performance can sometimes be poorer than a dipole depending on direction." True, and in the directions those radiation lobes point a K2 will be as loud as many 100 watt rigs feeding into halfwaves and verticals. A 120 foot long doublet between 30 and 60 feet up will show a number of lobes at very low angles with a gain of between 7 and 10 dbi on 20 meters and up. Great gain for little money. It's just a real pig to rotate. Ron AC7AC K2 # 1289 +++++++++++++++++++ Date: Tue, 30 Oct 2001 17:05:43 -0600 From: "George, W5YR" Subject: Re: [Elecraft] 44' Doublet Not to beat on a dead horse, George, but the simple truth is that your 51 ft wire will radiate as well or better than a 44 ft wire if you feed each with ladderline and a tuner. The difference in radiation efficiency between those two lengths would be trivial for amateur purposes even if it could be measured. Your problem with the "G5RV" is with the feed system, with its hybrid twinlead or ladderline and coax, not the length of the flat-top. I use two 88 ft doublets (at right angles) each fed with ladderline and a tuner. Excellent performance and loading on all bands 80 - 10 meters. Plus 3 db gain on 20 meters and gain above a dipole on all bands above 40. Four lobes on 10 but each lobe has more gain than either lobe of a 10-meter dipole. - -- 72/73, George W5YR ++++++++++++++++++++ Date: Tue, 30 Oct 2001 17:54:15 -0600 From: "Stuart Rohre" Subject: Re: [Elecraft] 44' Doublet If I remember L. B. 's paper correctly, his point was that the 44 foot length had more "dipole" like radiation pattern, ie, off the sides of the wire at right angles to it. That was Cebik's objective, to model a smaller than resonant wire, that preserved most of the traditional two dipole lobes. 72, Stuart K5KVH The 51 foot antenna may have more lobes, and smaller ones, thus favoring narrow directions rather than two main directions. Both types would be greatly affected by elevation over earth as L. B. points out. ++++++++++++++++ Date: Wed, 31 Oct 2001 00:27:23 +0000 From: Larry Cahoon Subject: Re: [Elecraft] 44' Doublet > >51 ft G5RV .. just unconvinced that 44 ft is not better than 51 ft, both >with ladder line, tuner, etc. The answer to this is in Cebik stuff and what you want to do. The longer antenna divides into multiple lobes as a lower frequency. That is why Cebik uses 44 ft for 40m to 10m. Make it any longer and you get multiple lobes on 10m. The 88 ft version goes to multiple lobes at a lower frequency. On something like 20m the 44ft and 51 ft won't make a lot of difference. The 51 ft will have a little more directivity and gain off the sides of the antenna and perform less well off the ends of the antenna. If you only have one antenna using the 88 ft version for 20 meters might do great off the sides of the antenna but is like to do a lousy job off the ends. The real issues is what do you want to do, and how much gain to you want to have in some favored direction at the expense of poorer performance off the ends of the antenna. I've got a 20 m dipole fed with coax running east west and a 44ft version with ladderline running north south. Each has it's advantages and disadvantages. I've heard FL at 599 from the dipole and nothing from the 44 ft job. I've worked Doc in ND with the 44 ft job at 500 mW and could hardly hear him on the dipole. Best game in town is multiple antennas. If I had only four I'd run two each of the 44 ft and 88 ft doublets with one of each running north-south and east-west. Then I'd start playing with the elevation of each to get the "best" takeoff angle for the lobs so I could get the area of the county/DX I wanted. 73 de Larry.............WD3P in MD\ http://www.qsl.net/wd3p/ +++++++++++++++++++++ Date: Tue, 30 Oct 2001 22:06:21 -0500 From: "Mark J. Dulcey" Subject: Re: [Elecraft] 44' Doublet Phil Wheeler wrote: > >>Not to beat on a dead horse, George, but the simple truth is that your 51 >>ft wire will radiate as well or better than a 44 ft wire if you feed each >>with ladderline and a tuner. The difference in radiation efficiency between >>those two lengths would be trivial for amateur purposes even if it could be >>measured. >> > > I'm not sure, George. Cebik has quite a bit of analysis data at his > website that indicate 44 ft to be a good choice for 40-10 m and 88 ft > for 80-10. His recommendations and analysis are usually very good. The advantage of the 44' length (or the full 88' version for 80-10) is that the direction of maximum radiation is basically constant on all bands - in other words, you can set it up broadside to your favored direction, and it does the right thing everywhere. The 51' antenna does not have that property. Either antenna will be an efficient radiator when fed with open-wire line. The only question is - an efficient radiator to where? Of course, if the direction of your antenna is dictated by property constraints rather than chosen direction of radiation, it's possible that the lobes of the 51' antenna on the higher bands would be more favorable for you than the lobes of the 44' antenna. (As usual, neither antenna will be very directional on the lowest band of operation, especially if it's not up high.) ++++++++++++++++++ Date: Tue, 30 Oct 2001 20:16:50 -0700 From: "Len Koppl" Subject: [Elecraft] Wire antennas There is a lot of discussion of 44 ft vs. 51 ft, etc. The full sized G5RV was set to 102 ft because that was the size of Louis Varney's (G5RV) lot. He did a little analysis to determine a 300 ohm feed line length that would allow his tuner to adequately transform some crazy impedance to 50 ohms on 80 - 10 meters, allowing his rig to put out full power. As it turned out, the antenna system was resonant on 20 meters. Louis recommended against a balun, as the impedance being transformed was different on each band, so a 4:1 might be right on some bands and a 1:1 correct for another (20 meters in his case), and he felt it would probably add loss. The 51 ft length came from the 'half sized' G5RV that allows for a smaller lot. It is not a magic or even preferable length for an antenna, it is just a convenient length. I read Louis' article (someone copied it from a magazine and sent it to me. Sorry, I don't know which mag). I decided that there were no critical values involved, so I bought two 50 ft lengths of Radio Shack antenna wire, some dog bone insulators, and 100 ft of 450 ohm window line. I assembled it, and put it up about 30 ft high, sloping off both sides, one side more than the other, with a bend in the last 10 ft of one leg. I cut enough feed line to reach the house (40 ft?), then directly (i.e. no balun) tied the window line to about 15 ft of 50 ohm RG-8. I wound about 10 turns of the RG-8 into a 6 inch circle to provide a choke to keep RF out of the shack. As it turned out, without measuring any antenna or feed line lengths, it came out resonant on 40 meters, and I can run there without a tuner over most of the band. All other bands 160 - 10 work fine, but need a tuner. (I just got lucky on the 160...) It works everywhere, but does not perform like my beam so it really only gets used on the lower bands. For camping, Field Day and the like, I built a similar antenna. It is 200 or so ft long (100 ft per leg), fed with el-cheapo hamfest special 300 ohm twinlead. I simply clip-lead the twin-lead to the coax, and let the KAT2 tuner do its thing. It works really well, costs next to nothing to build, and took less than an hour to round up the parts and solder it together. Moral of story: Beams work WAY better than wire antennas. Simple antennas work. Longer is better. Higher is better (except when working close-in...). Don't angst over a few feet of wire one way or the other. The KAT2 tuner is *AMAZING*. 73, Len Koppl, KDØRC K2 #2239 ++++++++++++++++++ Date: Wed, 31 Oct 2001 17:35:41 -0800 From: Phil Wheeler Subject: Re: [Elecraft] 44' Doublet There is a configuration called a Skelton antenna which is two inverted Vees in that configuration. The last time I was there, Doug Hendricks had one on his house .. several years back. It's not really a cruciform but more of an X. I don't recall the element lengths. Ah .. here is a web site describing it: http://home.pacbell.net/serazin/cone.html I learned about it in the NorCal QRPp. 73, Phil +++++++++++++++++++ Date: Thu, 01 Nov 2001 10:13:31 -0800 From: Vic Rosenthal Subject: Re: [Elecraft] 44' Doublet "George, W5YR" wrote: > > I failed to point out that a major problem turned out to be keeping the > lines from tangling with the clamps on the push-up RS mast. My experience with antennas has led me to believe that there is a special set of corollaries to Murphy's law regarding this sort of thing. With apologies to the physicists, I call it 'string theory'. 1) Anything longer than it's wide is a string. 2) Any string that passes within a minimum capture distance of another string will be attracted to it. 3) Any two strings that touch WILL tangle. 4) Although tangles occur when both ends of both strings are constrained, it's almost always necessary to free one end of a string to untangle it. 5) No matter how neat a coil is, and no matter how careful you are in unrolling it, you will get a major tangle. 6) Copperweld belongs to the Devil. You get the idea.... 73, Vic, K2VCO Fresno CA ++++++++++++++++++++ Date: Mon, 12 Nov 2001 22:18:27 -0500 From: brickle To: qrp-l at lehigh.edu Subject: [111413] Re: 88'/44' Doublet antenna questions Message-ID: <3BF09103.3459FE38 at pobox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Rod -- > Before investing a lot of time to reproduce already available results; > for the 44 foot version: I'd like to know if heights below 20-30ft are > workable with this design, and if the K1 can tune it. If so I might > like to try this antenna. While I'm asking, has anybody tried this > doublet implementation in a sloper or Inverted-V configuration? I've used several versions of the 44-footer for the last seven months. Variants include -- inverted-vee, feedpoint up 25', fed with 300-ohm twinlead -- inverted-vee, feedpoint up 20', made from one piece of zip cord -- flattop, up 15, twinlead -- flattop, up 20', all zip cord -- flattop, up 20', fed partway with homebrew shielded balanced line (RG-59 so 150 ohms), remainder with 300-ohm twinlead -- flattop, up 25', 300-ohm twinlead. The last version I put up to use on Field Day and have left it up ever since as my only QRP antenna. (Contests too, since I'm only doing contests QRP anymore.) All the others were portable in the wild -- woods, NE mountaintops, etc. with improvised suspensions. Can't speak to the K1, but all of them tune just fine with the Z-11 and a 4:1 balun on all bands 40-10. Most effective on 30 and 20 meters. Didn't do too badly in the IARU event on 15 and 10 QRP SSB, either. Tunes on 80 but I haven't really wrung it out there. The open-line version is probably much preferable, since changes in moisture and temperature do affect the tuning quite a bit from day to day with the twinlead feed. 73 Frank AB2KT ++++++++++++++++ Date: Tue, 13 Nov 2001 09:30:33 -0500 From: Bill Coleman To: , "Low Power Amateur Radio Discussion" Subject: [111432] Re: 88'/44' Doublet antenna questions Message-ID: <1011013093033.JAA28770 at gate.iterated.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" On 11/12/01 8:49 PM, Rod N0RC at rod at n0rc.com wrote: >Before investing a lot of time to reproduce already available results; >for the 44 foot version: I'd like to know if heights below 20-30ft are >workable with this design, The key dimension in any horizontal antenna is height above ground in wavelengths. Whether it is 44 or 48 or 40 feet long won't matter nearly as much as how high it is above ground. LB specified 88/44 feet because the resulting pattern is still close to broadsided at the highest / lowest bands of use -- there are no deep broadside nulls -- AT A SUITABLE HEIGHT. Look at the tables in the article carefully. The first set is for free space. The next set is at 70 feet, and the remainder all at 100 feet. This is all for the 88 foot design -- similar results would be had for the 44 foot design at 35 and 50 feet. If you place these antennas at significantly lower heights -- they won't perform the same. The end nulls will disappear, and the entire lobe will go upward toward higher angles. If your goal is short-range communication, that might not be too bad. But if you want to work DX, getting height is more important. -- Frankly, it disturbs me that LB Cebik's article seems to be taken as a magical formula -- just cut the antenna for 88 or 44 feet and it will be great. This neglects the antenna wisdom that the most important aspect of any horizontal antenna is the height above ground in wavelengths. Bottom line: (for any horizontal antenna <1 wavelength above ground) Getting the antenna up high will do more for its transmitting and receiving qualities than any particular change in the length. Footnote: I have a 105' doublet at 35 feet I use on 80m. Yes, I'd like it to be higher, but no, I don't have suitable supports. I do the best I can. You should, too. Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr at arrl.net Quote: "Not within a thousand years will man ever fly!" -- Wilbur Wright, 1901 ++++++++++++++++++ Date: Tue, 13 Nov 2001 09:43:20 -0500 From: Bill Coleman To: , "Low Power Amateur Radio Discussion" Subject: [111433] Re: 88'/44' Doublet antenna questions Message-ID: <1011013094320.JAA00251 at gate.iterated.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" On 11/12/01 10:18 PM, brickle at brickle at pobox.com wrote: >>While I'm asking, has anybody tried this >> doublet implementation in a sloper or Inverted-V configuration? Oh, and Rod, a sloper or Inverted-V configuration will change the pattern dramatically. A sloper exhibits gain not so much in the broadside direction, but more toward the low end of the sloper. An inverted V tends to rob gain from the broadside direction, and fill in the nulls off the ends. An inverted V doesn't offer the maximum gain of a flattop at the same height, but it does have more omnidirectional coverage. Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr at arrl.net ++++++++++++++++++ Date: Sun, 17 Mar 2002 13:44:50 -0500 From: "Pastor-KC1DI" To: , "Low Power Amateur Radio Discussion" Subject: [122351] Re: Antenna question... trap dipoles ----- Original Message ----- From: "Mike Yetsko" To: "Low Power Amateur Radio Discussion" Sent: Sunday, March 17, 2002 11:09 AM Subject: Antenna question... trap dipoles > Time for a more serious QRP question... > > I have a 40M dipole up that works gangbusters on 40M. I feed it with > 300ohm twinlead from my K2 equiped with an ATU. > > Now, I'm really pleased with what it does. > > But... > > I was just wondering... While the K2 can bring it in to at worst case > an SWR of 1.3:1 on ANY band from 80 through 10, there's gotta be > wierd feed line radiation and looses. So, if I were to put up a TRAP > dipole... > > I know, make all those little coil-and-cap arangements for 10-40... > PITA. > > But will I see a REAL difference in performance? Inquiring minds want > to know! Or at least have an idea of a reasonable expectation before > I start scrounging for caps and winding toroids. > > Mike > > Mike , You may and may not see a difference.. your going to trade some power to change the antenna pattern. your forty meter dipole fed with 300 ohm line ( I'd Change to 450 or home-brew some real open wire if the run was more than 50 ft or so.) Will exhibit some gain on every frequency above the fundamental (in your case 40 M). Now here the catch in order to get gain at one angle or direction you must steal it from another. So as you go higher in frequency you will see lobes of greater gain in some directions (with respect to the wire) But at the same time you will loose that effectiveness in another direction. What the trap dipole will do for you is even out these lobes and make them nearly the same at all the frequencies you desire to work.. (By the way the loss in the mismatched line is minimal compared to the lose in coax that is miss- matched) In order to get this uniform antenna pattern you must be willing to trade off , a little power (lost in traps) and a narrowing of the bandwidth) Just a suggestion instead of changing to the trap dipole.. leave the one you have up (again I would go to other than 300 ohm line if possible) and put up a vertical to fill in the radiation pattern on those bands where there may be a null in some specific direction.. You will get more mileage that way I believe.. Or better yet if you have the room put up a 500 Ft. Loop at 30 ft or above fed with open wire line and enjoy operating.. I love the 500 ft loop I have.. and with a vertical to fill in the nulls on the upper bands it makes a great combo. Hope to CU on the Bands, 73/72 Dave KC1DI ++++++++++++++++++++++ Date: Sun, 17 Mar 2002 11:41:53 -0800 From: "Bob Tellefsen" To: Subject: [122357] Re: Antenna question... trap dipoles Mike As long as you maintain decent balance in your 300 ohm TV twinlead feeder, you will not have feedline radiation. That's the whole point of balanced feedlines. RF goes in at one end and comes out the other. Any losses along the way are due to physical characteristics of the line, not radiation. If loss is a concern to you, shift to 450 ohm window line. You won't see any improvement by going to a trapped dipole configuration. For example, with traps, each band has just a plain dipole to radiate from. With the 40m dipole run on higher bands, you actually have a gain antenna. On 30m, it's a about 1.4 halfwaves long, and has a small gain. On 20m it's two halfwaves in phase, with about 2 dB of gain. On the higher bands, there will be more gain, but the pattern will develope lobes pointing in other directions than at right angles to the run of the wire. I advise you stay with the tuned 40m dipole and enjoy the results. 73, Bob N6WG ++++++++++++++++++ Date: Mon, 18 Mar 2002 00:14:03 -0600 From: "Adrian Weiss" To: qrp-l at Lehigh.EDU Subject: [122400] Re: Antenna question... trap dipoles Hi all: Mike asked: "I have a 40M dipole up that works gangbusters on 40M. I feed it with 300ohm twinlead from my K2 equiped with an ATU. Now, I'm really pleased with what it does. I was just wondering... While the K2 can bring it in to at worst case an SWR of 1.3:1 on ANY band from 80 through 10, there's gotta be wierd feed line radiation and looses. So, if I were to put up a TRAP dipole... But will I see a REAL difference in performance? Inquiring minds want to know! Or at least have an idea of a reasonable expectation before I start scrounging for caps and winding toroids". No. In fact, given that traps introduce loss into the system, it is possible that you may notice a decrease in performance -- although not likely. The main difference that you will notice is a difference in radiation pattern. With the trap dipole, the radiation pattern will be broadside on all bands. With the 40m dipole, the main lobes begin splitting into four-leaf and then more lobes which mean extra coverage on the high bands. In addition, the gain of the 40m dipole increases as you move up the high bands. So, in addition to introducing loss, you will be lessening your high band coverage. You could give it a try anyhow. 72, Ade W0RSP +++++++++++++++++ Date: Mon, 18 Mar 2002 00:35:29 -0600 From: "Adrian Weiss" To: qrp-l at lehigh.edu Subject: [122401] Shortened Dipole Concept -- SPRAT Autumn 1990 Hi gang: Shortened horizontal antennas are a frequent topic here, so Gus Taylor, G8PG's article in SPRAT Autumn 1990 might be of interest to apartment dwellers and other space-challenged QRP'rs. Gus notes that the concept goes way back beyond 1975 when he first wrote it up for the second issue of SPRAT (took up where THE MILLIWATT left off). The concept is simple: an end portion of the radiator on each side is folded into a non-inductive set of "U" shaped folds. This end loading has the benefit of raising the feedpoint impedance, which is always low or very low on a shortened ant. His model antenna is designed for 20m, so a pair of 16.5ft wires are cut (dipole = 33ft total). As usual, the inner ends are attached to some sort of center insulator to which the twinlead also is attached. He chose a reduced length of 10ft, which means that each side has an inner radiator of 5ft length, leaving 11.5ft to be folded. The folding technique employs a flat piece of cardboad 14in x 12in. Nine holes are punched along the two 12in sides. The holes are 1in apart. They can be numbered, for illustrative purposes, as follows: TOP ROW (12in edge) 1-4-5-8-9-12-13-16-17 BOTTOM ROW 2-3-6-7-10-11-14-15-18 The extra 11.5ft is fed inthru hole #1, stretched 14in across the baord and thru hole #2, looped to hole #3, across the board to hole #4, looped to hole #5 and so on until the extra 11.5ft is all in place. Gus used 15ft of cheapie twinlead -- don't roll it. If it is too long, then zigzag it with curved bends etec. Naturally, it is fed with a balanced tuner. Gus was surprised that he could make many 40m QSO's with it although it is rather inefficient on that band. The attractive feature of the antenna is that it will tune up and work on the higher bands as well. At 10ft, it will find space in all but the smallest apartments. If anyone tries it, let us know how it does. 72, Ade W0RSP +++++++++++++++++ Date: Wed, 17 Apr 2002 10:11:29 -0400 From: "Hartwell, Martin E, ALINF" To: Subject: [124949] Doublet antenna Hi >From my personal experience a Doublet of about 80 feet per side, fed with window 450 ohm line at 60 feet in the air in inverted V fashion has both vertical and horizonal properties and worked well. So I have to agree with Bill on this, I had tried the multiple dipole elements and=20 found better results with the single doublet, and easier to manage with the single support too. Marty kd8bj PS. Wish I could do the same at my present location. When I want to operate now I use the same antenna at a local park again easier to hang. +++++++++++++++