++++++++++++++++++++++++ See also Covert Antennas ++++++++++++++++++++++ Date: Fri, 30 Mar 2001 16:57:07 -0700 From: Larry East Subject: Re: [Elecraft] Am I getting out???? At 02:38 PM 3/30/01 -0600, Stuart Rohre wrote: >Toby, >I maybe did not make clear; my random wire did make local contacts, but DX >is what we all want, right? For DX, a single wire has a directionality that >greatly limits what you can do. On the bands 20m and up, we all can likely >put up some dipole, even if short, and thus benefit from a balanced antenna >independent of an earth connection except in the reflection. I have a end-fed 450 length of wire up 20 feet (more-or-less, depending on droop and the lay of the land) running up a small hill behind my house in an easterly direction. It is a darn good DX antenna on 20M and up (sometimes for 40 and 30 as well -- depending on direction). A wire that long has multiple lobes for the higher bands so one is not confined to working in one or two directions. Of course, it might be a little difficult to string up something that long in an "urban environment" unless your are really, really sneaky! :-) 73, Larry W1HUE/7 PS -- "How do you feed it" you ask? I have a 9:1 transformer at he base and feed it via RG-8X against ground (just a ground rod -- no counterpoise). I get a good match on all bands from 40 thru 15M, but the feed impedance bounces around quite a but on 12 and 10M. But the K2 auto-tuner handles it with no problems. It even works as a transmit antenna on 160 and 80 in spite of its low height. +++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Sat, 31 Mar 2001 23:43:26 +0100 From: "David Johnson" Subject: [Elecraft] Stealth antenna Of the various cheap and simple antennas I've used over the years, a doublet seems to perform as well as any. It depends on circumstances, but they can be made very inconspicuous if needed. You will need an ATU of some sort as well as a 4:1 balun. My doublet seems to work very well on the K2, it's got a 100 foot top, elevation 30 feet, about 25 foot of open wire feeder, feeder and top section single length (for each side) of 32 strand black pvc insulated hookup wire, 4:1 balun in plastic box, hole through wall into upstairs shack, 3 feet of UR-76 coax to VCI ATU. Tunes 80 to 10 with no problems and gives plenty of DX contacts. Dave, G4AON K2 #1892 ++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 1 Apr 2001 10:19:53 -0400 From: "Francis Belliveau" Subject: Re: [Elecraft] Stealth antenna Lamar et. al. An antenna that takes the shape something like ---- -| <--> radiation ---- Allows a full sized 20 meter antanna in a 10x10 room. Preferred radiation pattern is also indicated. Obviously 10 and 15 meters can also be supported from such a configuration. If you are lucky and have a convenient door nearby you might combine 2 rooms to get 40 or 80 metters worth of wire. To complete the picture above run your feedline up the center of a wall to the ceiling. Secure that location as your feedpoint and run an equal amount of wire out from there. How much wire you can put up depends upon room geometry. You can go out along the wall containint the feedpoint or straight toward the opposite corners. I ran a 15 meter resonant antenna from a first floor room for my HW-8 and it worked quite well. Measure out the space you have, add up the available places you can run wire and see what fits. From the second floor I expect that a dipole or doublet are your best indoor bets. I used transformer wire supported at the ends by common pins and it was virtually invisible. I used a poster to hide the feedline. Fran ++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 1 Apr 2001 14:23:44 EDT From: Edgerhardt at aol.com Subject: Re: [Elecraft] Stealth antenna Lamar, I live in a condominium populated largely by elderly condo commandos who would be delighted to catch me operating from my 2nd floor QTH. I have experimented with the B & W portable that I would hang out the window, with inside dipoles and a few other ideas involving loops. My advise to you is simple. Get a roll of 26 gauge wire from Radio Shack and string as long of a run as you can get out to the nearest tree or similar structure. Mine runs about 70 feet in a slope from my second story window to a tree on the bank of a lake. I had also tried a longer run up to the roof. No one can see it and best of all, it works surprisingly well. I use a ZM2 tuner with counterpoises for each of the bands. I have worked over 30 States and 35 countries since completing the K1 on 2/23/01 in casual operating. Some highlights include Easter Island and the Gambia, somehow getting through big pileups both times. Many times the DX station seems amazed at the power. This setup is very directional on 20.....I get into Central Europe quite well, often getting 599 reports.....I must have a million Croatian and Macedonian contacts in the log. I do not get out that well to South America on 20, despite the relative proximity (Miami, Fl). 40 also works well on this antenna into Europe and of course into the Caribbean, which is really a local contact. I have used it on 80 with my venerable HW-8 and in fact have worked Northern Europe on a couple of occasions. I have done some comparisons with using 100 watts into the B & W antenna versus 5 or less into the random wire. The random wire does a lot better, even at lower power, than this short, coil loaded antenna sticking out of my window. Of course I have to tip my hat to the Elecraft design team and say that much of my success has been the great RX and easy operating features in the K1, not to mention the Mojo which comes for free. Bottom line, IMHO if you can put anything outside, you are better off by far. The drawback to this approach is that one feels rather conspicuous putting the antenna up. I generally wait until the sun goes down. Also, put it high enough so that someone will not accidentally walk into it. You will find that you will have to replace it occasionally as it will break, but so what, it is not expensive. 73 Ed N4EJG In a message dated 3/31/01 10:16:03 AM Eastern Daylight Time, n3at at enter.net writes: << In May I will be moving into a second floor apartment, and will likely need an indoor antenna for my K1 and K2 rigs. Is there anyone who has experience with any of the available antennas that can be used indoors who could give me some advice as to which one would be the most disirable to use? There is one that uses a "slinky" style of wire, and then there is the MP1 that may possibly be used on a tripod, and hamstick has an arrangement that used 2 hamsticks as a dipole. Are there any thoughts about one of these that might steer me in that direction? Or are there some others that I am not aware of? Any advice would be greatly appreciated. 72 de Lamar, N3AT +++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 1 Apr 2001 19:55:33 -0500 From: "David Bixler" Subject: RE: [Elecraft] Stealth antennas Hi Lamar: I've been watching this thread with interest. The suggestion I wanted to make is a source of "invisible wire" that I have used for years when stealth antenna were needed. I found that the ringer coils in old fashioned mechanical telephone ringers have hundreds of feet of small gauge wire on them. Not sure of the wire gauge, but it is probably 32 gauge or so. Really thin stuff and makes for very hard to see antennas. I used this wire successfully when I was living in boarding rooms at college and later many times at hotels for undercover operating. The old telephones are often found at yard sales and go for a quarter or fifty cents around here. Look for the phones that "ding" when you tap or shake them and have a mechanical ringer loudness adjustment on the bottom. 72 and good luck, Dave David Bixler W0CH - VK2IQX Seneca, MO Main Web Site: http://www.qsl.net/w0ch Mirror Site: http://showcase.netins.net/w0ch QRP: Little Radios, Big Fun! ++++++++++++++++++++++++++++++++++++++++++ Date: Mon, 2 Apr 2001 09:30:07 -0700 (PDT) From: Clark Savage Turner Subject: [Elecraft] Stealth Antenna - large, invisible loops Just a note about loops.... I have a medium sized pine tree in my backyard (of the duplex.) I took my fishing pole and cast monofilament (maybe 10 lb test) over the top and ran thin wire over it, bringing the wire together under the tree inside the bottom branches. Some coax running up the trunk to the loop to feed it. Got 130 feet of wire around the perimeter of the tree, full wave for 40. Vertical polarization. Coax up trunk and along the ground. Can't see a thing. Gets out quite well. I'm happy with that one. Clark WA3JPG +++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Mon, 2 Apr 2001 09:48:12 -0700 From: alta Subject: [Elecraft] Stealth Antenna - House Wiring is a Shield My experiences with apartment stealth antennas: To make a long story of many experiences short, I came to the conclusion that the house wiring forms a kind of a shield that can seriously get in the way of a transmitting antenna. Two things that worked for some degree for me. This was 7 years ago, so the memory is a little rusty: (1) Inductive coupling to the aluminum gutter. I think I used a loop from the antenna tuner to couple to the gutter. As I recall, about 4-6' along the gutter. I was able to do this with some difficulty by reaching out the apartment window. (2) I discovered how to get into the attic of the apartment, and put a dipole with curved ends along the top ridge of the roof. I expect it was cut to 1/2 wavelength. This was at least 6' above any romax (110v) wiring. This worked best of all the experiments. (3) This was one of the experiments that did NOT work all that well for communications, but did have the advantage of lighting up nearby fluorescent lights, a real crowd-pleaser: A double Spyder antenna, with the top half in the attic, and the bottom half in a spare room. (not recommended). I did not try any fine outside wire to trees, which I expect would have worked as well or better than anything else I tried. Another 2 cents worth ... Reed K7FLY ALTA RESEARCH . www.alta-research.com . alta at alta-research.com . 541-929-5738 (Running Linux . Caldera 2.4 Technology Preview release) ++++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Mon, 2 Apr 2001 14:43:15 -0500 From: "Stuart Rohre" Subject: Re: [Elecraft] Stealth antenna When you are using very fine wire, a whole raft of insulators come to mind, parts of plastic picnic pak forks and spoon handles, Coat buttons, and ball point pen plastic case parts. 72, Stuart k5KVH +++++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Wed, 30 May 2001 19:08:36 -0400 From: "Morrow, Michael A." Subject: RE: [Elecraft] rubber ducky > A rubber ducky comes to mind, for, although inefficient, at least I > can make some local contacts to bring up my code while I address my > antenna problem. But I know nothing at all about them. Do they exist > for, say, the 10-20 meter bands? Has anyone had success using them > with the K2? Any recommendations? I didn't see anything in the list > archive. > - -- > Haines Brown > Haines, The closest thing I've ever seen to an HF "ducky" would be the "Slinky (sp?) Dipoles" that were marketed for years in the ham magazines. These had each leg made from a "slinky"-type of coil (considerably larger in diameter than the toy slinky). It was actually quite well made. I bought one in 1980, and used it in a couple of apartments. It would actually work, somewhat. In any case, it worked better than a reasonable person would have expected. Using my TS-120S with it tore up other people's stereo in the adjacent apartments, for sure (which was not necessarily a negative feature). I don't know if these are still made or not. 73, Mike / KK5F +++++++++++++++++++++++++++++++++++++++ Date: Wed, 30 May 2001 21:35:53 -0400 From: Subject: Re: [Elecraft] rubber ducky Julian, Thanks for the reply. > I've never used a rubber ducky with the K2 but I did work from the > UK to Malta on 29.4MHz using one with 4 watts of FM and a hand-held > CB type transceiver. I wouldn't honestly recommend a ducky > however. It's probably easiest to work DX on 10 FM than on any band > when conditions are open. But the K2 doesn't do FM and I doubt if a > ducky'd cut the mustard on SSB. Yes, that seems to be the consensus of the many kind replies I've received. Also, on lower frequencies with larger "duckies" or loaded whips, mechanical stress becomes a concern. > The MFJ magnetic loop would certainly fit on your balcony and > performs comparable to a full size dipole or vertical. While a loop can be small and perform well, I don't know that I can use it. I live eight floors up on the side of a steel building and access the sky from a steel balcony below another steel balcony. My understanding of a loop is that it is particularly sensitive to conductors located in its near field. I'm afraid that with steel above, below and behind, it won't perform at all well. But permit me apply this perspective to a long wire antenna. I could probably get away with a full half wavelength #30 or thinner wire dropped straight down with a fishing sinker at the end (that is, when the wind does not blow). I know that such an end fed long wire should be over a quarter wavelength from the steel building it parallels, but that seems impractical at 20 meters or below. How do I calculate the loss resulting from a passive element (the building) located less than a quarter wavelength from the fishline driven element? Another question concerning such a "fishing line antenna" if you will allow. Ideally I guess I should feed it with 450-ohm open wire twin lead from the KAT2. But how does one hook that feedline up at the K2 end and at the antenna end? - -- Haines Brown brownh at hartford-hwp.com www.hartford-hwp.com KB1GRM ++++++++++++++++++++++++++++++++++++++ Date: Wed, 30 May 2001 22:12:48 -0600 From: Larry East Subject: Re: [Elecraft] rubber ducky At 09:35 PM 5/30/01 -0400, KB1GRM wrote: >But permit me apply this perspective to a long wire antenna. I could >probably get away with a full half wavelength #30 or thinner wire >dropped straight down with a fishing sinker at the end (that is, when >the wind does not blow). ...etc... Another possibility is a "helix" wound around a fiberglass (or even bamboo) fishing pole. I used such an antenna once when living on the fifth floor of a reenforced concrete building. The pole was about 12-ft long and wound with #14 insulated wire to resonate (as a 1/4 wave monopole) against ground on 40M. I clamped the pole to my balcony, with the pole sticking over the balcony at about 15-20 degrees above horizontal. For a "ground" connection, I used the steel balcony railing which appeared to be grounded somehow (probably thru the building structure). The antenna worked quite well on 40 and 15M (but I did use a tuner). When not in use, I simply unclamped the pole and laid it on the balcony. :-) 73, Larry W1HUE/7 ++++++++++++++++++++++++++++++++++++++++ Date: Thu, 31 May 2001 06:50:21 -0700 (PDT) From: Jeff Burns Subject: Re: [Elecraft] rubber ducky Date: Wed, 30 May 2001 21:35:53 -0400 From: Subject: Re: [Elecraft] rubber ducky "While a loop can be small and perform well, I don't know that I can use it. I live eight floors up on the side of a steel building and access the sky from a steel balcony below another steel balcony. My understanding of a loop is that it is particularly sensitive to conductors located in its near field. I'm afraid that with steel above, below and behind, it won't perform at all well." The loop may work better than you think. The building will effect the radiation pattern but the antenna will still work. An electrostatic shield on the antenna may be helpful. Before you spent the money on a commercially made loop you can make a prototype for $20. Get some aluminum foil duct tape. I just bought a 2.5 in. wide role for $12. Then get a flat board. Foam-core dry mount board works. Cut the corners of the bard off at a 45 deg angle. Wrap the foil tape around the edges of the board. Start the tape near one of the edges, but all on the first face of the board. At the corner wrap the tape around the 45 deg cut so that the tape continues around the board on the second face. On the last side of the square overlap the tape with an insulator in between. The insulating material can be wax paper, Mylar film, a plastic transparency, etc. In the overlapped section the first piece of tape is stuck to the board. The second piece of tape is stuck to the insulating material. The second piece of tape needs to be stiffened. To do this use double sided tape to stick the flap of tape to a small piece of board material. Tape one end of the board down. This creates a hinged flap. By varying the opening of this flap the capacitance is changed and the loop is tuned. Make a second loop from wire that is about 1/5 the diameter of the bigger loop. This goes inside the bigger loop, and connects to the transceiver. "But permit me apply this perspective to a long wire antenna. I could probably get away with a full half wavelength #30 or thinner wire dropped straight down with a fishing sinker at the end (that is, when the wind does not blow). I know that such an end fed long wire should be over a quarter wavelength from the steel building it parallels, but that seems impractical at 20 meters or below. How do I calculate the loss resulting from a passive element (the building) located less than a quarter wavelength from the fishline driven element?" You can try a resonant sleeve dipole. Hang a section of coax off the balcony that is half the length of a dipole. At the far end attach a wire to the center conductor that is the length of the other half of the dipole. At the point were the coax should stop acting as half of a dipole and start acting as a feed line make a small coil of the coax. You can use a pole to hold the antenna out form the building. Jeff Burns AD9T ++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Thu, 19 Jul 2001 14:09:29 -0500 From: "Stuart Rohre" Subject: [Elecraft] Stealth long wires, and more successful radiation antennas Hi, This is a common problem, someone needing to operate with little attention to themselves, and low visibility antennas. First of all some mechanics: No. 26 enamel wire is going to be pretty flimsy, and will easily be broken in friction of limbs blowing in the wind. You may want to live with having to splice pieces back together every few days, if in a windy area, but there are MUCH BETTER solutions both mechanically and electrically. You could go with a slightly heavier gauge, such as 24, and for low observability, spray paint the wire with flat black paint. Once high enough in the air, it will fade into the sky background, and the only thing you will see is a bird perching in mid-air! I have a local friend who does this with his low band dipole. Now as to length, and height. You need to have it up high enough that folks will not see it, but also, if you make a wire a wavelength or better, at a frequency, it is too directional to the far end of the wire, limiting your contacts to one direction. The longer the wire is, the more directional it becomes, and you likely would like more than one direction, unless you are on the tip of FL and can direct the wire NW or N! Bending the wire might help, but can cancel radiation, as I found out with a quarter wave on 40m. In general, I have had single wires from quarter wave on 15m and 40m to 400 feet long, and none of them worked worth a flip! The key was in not having an adequate counterpoise. You can use the 40m counterpoise on 15m, but you MUST have full length for 40m to work well. It needs to be run as straight as you can, but around the base boards of the apartment if no other way is possible. Better to also have it outside, running along the side of the building. Again, you may need to paint it a stealth color. However, my preferred stealth antennas are dipoles, using buttons as insulators. Or even synthetic fishing line. Run the center back to the eaves of the apartment or under the balcony where you can use TV twin lead to feed it. Anyone seeing twin lead will think TV, and not give it further thought. Even better, is to run around under the eaves with a loop making it a wavelength at 40m if you can. Circle the building if at all possible to install. If not, you will be using a tuner anyway for other bands, so it will do what it can to make it useable. Even run one side under the edge of the roof, or in a plastic gutter, and three sides out to the woods. You can support the wire, (if no plastic gutter), either on TV standoffs, or Electric fence insulator standoffs hung under the eaves. Screw in TV insulators are available at Radio Shack nation wide. Again use small wire, such as 24, and paint it to match the eaves color. The center of the dipole is low impedance thus can be brought close to the balcony, or a window for feeding without much loss. The window can have a thin board inserted at the bottom or even a piece of flexible pipe foam insulation. Poke a hole thru it for the twin lead, and simply close the window sash collapsing the tubing to a flat oval and you are in business. Cross the window sill at right angles, and there will not be losses even if it is metal sash. Another idea is to operate from a balcony if there is one, using headphones to avoid neighbor notice. When done, disconnect the feedline, and take it inside, and no one is the wise with the thin wire. If you operate with a 15m twin lead or ladder line fed dipole and tuner, you can make it work on 20m and 10m. Giving up 40m in the summer is no big loss, what with summer thunderstorms. Again, if possible avoid just running a wire straight out from the shack/rig, as that will limit your possible contacts to mainly one direction. Been there, done that, both as a US station and as a DX station with the 400 foot long wire. GL, and a low loop gave me over 6500 points in this last field day, it was only 20 feet high, about eave height on average building here. Of course, it was 849 feet around! But that is another story. 72, Stuart K5KVH To spray paint small wire, make a half circle from a piece of cardboard to confine the overspray, and make the spray reach all sides of the wire. Slide it along behind the wire as you spray, and you can paint a length, let it dry, roll it up, and unroll the next section to be painted, until all is done. +++++++++++++++++++++ Date: Sat, 21 Jul 2001 06:00:54 -0700 From: "Jerry T Dowell" Subject: [Elecraft] RE: Stealth long wires etc Stuart Rohre wrote: ""You could go with a slightly heavier gauge, such as 24, and for low observability, spray paint the wire with flat black paint. Once high enough in the air, it will fade into the sky background, and the only thing you will see is a bird perching in mid-air!"" My experience in active visual countermeasures (making aircraft disappear visually by judicious placement of lights of the right intensity) tells me that you don't want to paint the wire black for low visibility against background sky. You want to match the brightness of the background sky as closely as possible, so you want the wire to reflect as much light as possible, not absorb it. A dark color would be appropriate if people were looking at it against a dark background. It is amazing how bright the sky really is! A dark object really stands out! I have had good luck with long wires using wire as small as #36 or 38. You don't want to use anything smaller than 32 or the birds won't see it and they will fly into it. Circumventing CC&Rs is easiest with a dipole under the eaves. I used such a setup with about 105' overall length and it was good for over 280 countries from near the bottom of a canyon. 73 de Jerry AI6L +++++++++++++++++++++ Date: Wed, 15 Aug 2001 17:16:56 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] Question about a hunk o' wire Mike: As a Field Tester for the KAT2 and the KAT1, I threw just about anything I could think of at them and with VERY few exceptions, they tuned it with no complaining! I did, in most instances, have a 'counterpoise' wire attached to the case of the rig (more difficult with the K1 since It doesn't offer a ground terminal per se). But even when it wasn't connected, the ATU generally tuned to 1.5:1 or less. When no counterpoise was provided, I did find a much higher incidence of "RF in the shack" however. when I give presentations of the K1/K2, I usually take a 70' and a 30' length of wire. The 70' length (if I can get it stretched out), is usually connected to the center lead of a 15' length g-174/U coax thru 35 ferrite beads (a la W2DU 1:1 balun), and the 30' goes to the shield of the coax and often lays on the ground or over nearby bushes. When I've really cramped for space, I'll omit the coax/balun and go directly to the back of the ATU and to a ground on the rig. 73 - Tom Hammond N0SS >>I guess I should have clarified my question. I fully realize that actual >>performance of this hunk o' wire is more than likely dismal at best. I >>was just surprised at how easily the K2 loaded it up, particularly >>without any ground or counterpoise. I had expected the tuner to need >>some type of ground or counterpoise to effect such a good match. >Mike Boice, KW1ND ++++++++++++++++++++++++ Date: Fri, 17 Aug 2001 23:44:39 -0400 From: "Carl Morris, WN3DUG" Subject: [Elecraft] Fw: OT: Hanging wire from house soffit - ----- Original Message ----- From: Carl Morris, WN3DUG To: Sent: Friday, August 17, 2001 11:39 PM Subject: RE: OT: Hanging wire from house soffit Hi Mike, KW1ND, I'm also antenna restricted (Seems to be a lot of us out there), and recently came across an article from Craig LaBarge, WB3GCK, entitled "The WB3GCK Downspout Antenna". He uses his aluminum gutter and downspout for an antenna (It's now his main antenna!). His web site for information on this antenna is as follows: http://www.qsl.net/wb3gck/spout.htm I'm only passing this along for what it's worth. Take note of the safety measures mentioned in the article! By the way; I got tired of the "Covenant Police" and recently put up a nice Hustler 6BTV 10 - 80 Meter Vertical, mounted on a 4' piece of pipe in the back yard! I think it looks nice! First four contacts were 2 - Italy, 1 - France and 1 - Germany, on 20 Meters, so I think it's working! The K2 received stations on all bands, 10 - 80 Meters, with this antenna. No connection with Hustler, just a satisfied Customer. Good Luck! 72/73, Carl, WN3DUG K2 S/N: 1320 ++++++++++++++++++++++++++ Date: Sat, 01 Sep 2001 18:49:04 -0700 From: n3at2 Subject: [Elecraft] slinky A week or two ago, when I asked a question about an antenna for indoors, a "thread" started, and still seems to be continuing. With the help of Kb3BYT I tried a slinky on 20 meters, with good results, considering the fact that it is strictly an indoor antenna. My apartment manager doesn't want any outside antennas. We then tried using two slinkies as a dipole, strung out on two walls in an L shape. That did not work very well. I suspect that the soffit outside those walls was detuning the antenna. Today, with the help of K3PH, the slinky dipole was strong diagonally across the room, and there has been a great improvement in its performance. Contacts have been made on 40 meters, with S 4 and S5 reports from contacts made. With my LDG automatic antenna tuner, the swr was way down all the way across the band. And when I took the tuner out of the line, I was still able to get good results across the whole 40 meter band. The next project with be to try a loop around the room, near the ceiling. That was suggested by N3ZIL, who has some unique features built into his. After that, maybe we will give the old downspout antenna a whirl. But to do that, I must first finish the NJQRP rainbow tuner that I started building quite some time ago, and never finished, because I was then living in the woods, and had a great windom antenna that I wish I still had and could use here, But that won't happen. So I will keep on trying verious things until I come up with the ultimate solution for an antenna that will work best in the confines of an apartment. My thanks to all of you who have helped and encouraged me in my search for a solution to the apartment dilemma. 72 de Lamar, N3AT +++++++++++++++++++++ Date: Sun, 02 Sep 2001 12:53:10 -0700 From: lhlousek Subject: Re: [Elecraft] Antenna for hotels <<>> Pretty similar to the setup I use. I a have 40/20/10 meter dipole made from stranded ribbon cable. They run in parallel but the last half of each one is separated from the others. I use a 20' SD20 fishing pole (collapses to ~48") and have the center feed at the base of the pole with one leg of the dipoles running along the pole and hanging from the end. The other leg of the dipole is strung out in the hotel room serving as the other end of the dipole or a counterpoise depending on how you look at it. When traveling light I use a 14' fishing pole that collapses to 15" (Cabela's). This setup will tune on 80 thru 10 with the K2 and certainly 40 and 20 with my K1. Lou W7DZN ++++++++++++++++++++++ From: "Stuart Rohre" To: "Gay Family" , Subject: Re: [Elecraft] Stealth Wire Antenna Wisdom? Date: Mon, 4 Feb 2002 15:05:46 -0600 Besides the Les Moxon book, and the Bill Orr Antenna Handbook, a lot of information is on the Force 12 Web site. MFJ has reprinted a number of books and 73 Wire Antennas (Ed Noll) is one of the best. 72, Stuart K5KVH ++++++++++++++++++++++++ From: "Dave" To: "Mike Walkington" Cc: Subject: Re: [Elecraft] Stealthy Antenna Date: Mon, 20 Jan 2003 21:34:20 -0000 Hi Mike I've used a 100 foot doublet (dipole fed with open wire line) for several years and it works reasonably well. I have a 4:1 voltage balun in a plastic project box (the plastic version of a diecast box), it's mounted on the wall right outside the shack with 3 to 4 foot of coax straight into the K2/KAT2. I have sealed the box with silicon sealant and provided a small drain/breather hole at the bottom. The feeder connects via a pair of brass bolts/nuts with one on each side of the box. Not only does it look quite neat, it's given no trouble at all. I guess the open wire line is around 20 odd foot long. The "advantage" of the 4:1 balun is in it's centre tap to earth that drains any static from the antenna to an earth rod. The KAT2 tunes it to a reasonable match on most bands, but the feed impedance can be quite fierce on some frequencies. If there's a band you want and can't match, alter the antenna or feeder length to get a better match. You can model wire antennas quite easily with the free demo version of EzNec at: http://eznec.com There is a good description of the doublet by one of the most respected antenna modelling hams (L B Cebik, W4RNL) at: http://www.cebik.com/aledz.html Have fun Dave, G4AON K2 #1892 ----- Original Message ----- From: "Mike Walkington" To: "Elecraft Reflector" Sent: Monday, January 20, 2003 3:50 AM Subject: [Elecraft] Stealthy Antenna > All, > > I'm planning to use a short piece of co-axial cable (6-7 feet) to get from > my K2 (with KAT2) through the wall of the house to an externally mounted 4:1 > current balun (the W1CG model). From the balun I plan to run twin feed > (20-30 feet) to a doublet or loop mounted under the eaves of my two storey > house (to avoid the anti-antenna covenants). I have some questions about my > proposed configuration that I'd appreciate some advice on: > > 1) Can anyone offer some experienced advice on how long or short the co-ax > can be? > 2) Is it OK to mount the balun in a plastic box? > 3) Would you recommend a doublet or a loop? > > Mike > AC7MZ > K2 #2599 +++++++++++++++++