++++++++++++++++++++ Date: Wed, 25 Jul 2001 06:50:39 -0500 From: Mike Subject: Re: [Elecraft] 26 AWG, 19 strand copper-clad steel wire Jeff Burns wrote: > > I am considering using 26 AWG, 19 strand copper-clad steel wire for a > > new portable antenna. Mark J. Dulcey wrote: > You don't want to use copper-clad steel for this application - it's too > hard to roll up. The stuff tends to have a mind of its own. Regular > copper wire would be a better bet. I've been playing with portable backpacking/camping antennas for more than 25 years, and I agree with Mark about staying away from any kind of steel wire. It also is very subject to fatigue failure due to work hardening as the wire is manipulated (i.e., rolled/unrolled). I have found the FLEXWEAVE copper-strand wire to be the best wire for portable antennas that I've ever found, by a large margin. (There may be a similar product called SUPERWEAVE out there too.) Flexweave is sold at http://www.wireman.com, among other places. It's not cheap but its more than worth the price. If you've never seen this wire, you'd be surprised at it's extreme flexibility. It's almost like fine gold chain, even in the larger diameter AWGs. I'd recommend the 14 AWG version (consists of 168 individual strands) with or without the flexible jacket (there's a heavy jacket version that you probably would NOT want) for your application. The stuff is so flexible I use the larger 12 AWG bare product (259 individual strands!) for my portable dipoles. Mike / KK5F +++++++++++++++++++ Date: Wed, 25 Jul 2001 08:24:19 -0500 From: Jim Speck Subject: RE: [Elecraft] 26 AWG, 19 strand copper-clad steel wire Jeff Burns wrote: > > I am considering using 26 AWG, 19 strand copper-clad steel wire for a > > new portable antenna. Mark J. Dulcey wrote: > You don't want to use copper-clad steel for this application - it's too > hard to roll up. The stuff tends to have a mind of its own. Regular > copper wire would be a better bet. Well, I've had good luck using 18 ga. copperweld (single strand) for a portable antenna. It's self-coiling, and you don't want to crimp it, but it rolls up nicely in 5- or 6-inch diameter and lasts forever. I use waxed tie-cord for insulation and support. What I use I got at an aircraft electronic shop - they use it for sense antennas and HF for light aircraft. Jim Speck W5AI K2 #2019 ++++++++++++++++++ Date: Sun, 30 Sep 2001 00:47:22 -0500 From: Dave Gingrich Subject: Re: [Elecraft] QRP G5RV? At 15:05 9/29/2001 -0700, Stephen E. Stuntz wrote: >What's "Flexweave" wire and where do you get it? Is it like aircraft >antenna wire? >72/3 - Steve, K6FS Flexweave is most similar to the plain old 14 gauge, 7 strand copper antenna wire.. Except that it is 168 strands. Available from http://www.thewireman.com/ It is advertised as "tangle free" which is a bit of a stretch, but it is much more flexible and handles more like rope. You can tie a knot in it easily. As antenna wire goes, it is the nicest I've ever used, although it is a bit pricey. ===================== Dave Gingrich, K9DC +++++++++++++++++ Date: Sun, 30 Sep 2001 11:52:28 -0500 From: Dave Gingrich Subject: Re: [Elecraft] QRP G5RV? >Then, Dave Gingrich, K9DC, wrote: > >>Flexweave is most similar to the plain old 14 gauge, 7 strand copper antenna wire.. Except that it is 168 strands. Available from http://www.thewireman.com/ >> >>It is advertised as "tangle free" which is a bit of a stretch, but it is much more flexible and handles more like rope. You can tie a knot in it easily. As antenna wire goes, it is the nicest I've ever used, although it is a bit pricey. At 09:15 9/30/2001 -0500, Tom Hammond NØSS wrote: >Agreed... though, being a frugal (my kids call it 'cheap') kinda guy, I've found that, once in the air, the RF doesn't care whether its 7-strand of 168-strand. > >If you're only gonna handle it one time (putting it together and into the air), it's NOT gonna matter at all. > >If you're gonna make something that can be 'traveled' with, and routinely installed, taken down, wound up, and re-installed elsewhere, FlexWeave makes a bit more sense to me. It has MUCH less 'memory' with regard to wanting to re-coil when unrolled, and sometimes this is a BIG plus... esp. when it's a traviling antenna. Yep... In the same order I also bought 1000 ft of their single strand 18 awg, copper clad steel wire for $.037/ft. for my permanent antenna. You definitely don't want to mess with that stuff for portable jaunts. It's a great way to ruin a perfectly good vacation! ===================== Dave Gingrich, K9DC Indianapolis, Indiana Dave at dcg.org ++++++++++++++++++++ Date: Mon, 01 Oct 2001 01:30:36 +0100 From: "J. Ellis" Subject: [Elecraft] antenna wire Hi Folks, At the suggestion of Tom, N0SS, would like to suggest that any of you considering using "flexweave" antenna wire, consider your location. I tried some of that years ago, it didn't make it a month before falling apart due to corrosion from the salt air. Also, this "copperweld" antenna wire has some of the same problems. If the copper coating gets nicked, it exposes the steel, which soon turns to rust and the next thing you know, your antenna is all over the ground. Probably works fine in Kansas City or El Paso, but worthless in the Caribbean! For a fixed station antenna wire, ordinary 12 or 14 gauge THHN insulated stranded house wire is hard to beat if you are near the coast. John, NP2B K2/1645 (mature) K2/2281 (embryonic) +++++++++++++++++++ Date: Sun, 30 Sep 2001 22:17:40 -0500 From: Mike Subject: Re: [Elecraft] antenna wire J. Ellis wrote: > ... any of you considering > using "flexweave" antenna wire, consider > your location. I tried some of that years ago, > it didn't make it a month before falling apart > due to corrosion from the salt air. I'm sorry to hear that. I'm not sure I'd use flexweave for a permanent installation even inland, just because it would be extra expense for no good return. I think the 12 awg uninsulated stuff runs about $0.18 per foot. On the other hand, there is absolutely nothing I've run across in 30 years of making portable wire antennas that works better than the flexweave I started using about five years ago. It is *extremely* flexible, even in the 12 awg size that I use for all my camping dipoles. I've never found anything more durable, less subject to fatigue failure, or easier to handle than flexweave. It is the ONLY wire with which I've had no failures in any antenna I've ever built using it. Great stuff in the right application! 73, Mike / KK5F ++++++++++++++++++ Date: Mon, 1 Oct 2001 07:39:58 -0400 From: "Bob Lewis \(AA4PB\)" Subject: Re: [Elecraft] antenna wire One thing you've got to watch on ordinary copper wire is that it stretches. When I have used it I pre-stretch it before cutting it and putting it up in the air. I made an error in my last order for Copperweld and ended up with solid Copperweld wire. This turns out to have the advantage that it wants to unwind and lay pretty flat which makes it easier to work with than the stranded Coperweld. I've had stranded up for years and when I take it down it coils back up into knots. ++++++++++++++++++ Date: Mon, 01 Oct 2001 09:14:39 -0400 From: "David A. Belsley" Subject: Re: [Elecraft] antenna wire I note that there is a corrosion-resistant version of the flexweave wire. best wishes, dave belsley, w1euy +++++++++++++++++++ Date: Mon, 1 Oct 2001 11:16:58 -0400 From: Tim ORourke Subject: [Elecraft] Flexweave Wire There is a another type of flexweave available that has a strong core of sometype of fiber, may be kevalr but not sure. It is much lighter than Flexweave and makes great backpacking antennas. I have both types and the fiber core is much less likley to strech and more flexible. Problem is I can not remember who I got it from. I will look back over some receits. I have also used it for quads and it works great for this also. Tim O'Rourke KG4CHX +++++++++++++++++++ Date: Mon, 01 Oct 2001 09:57:33 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] antenna wire Bob, et al: >One thing you've got to watch on ordinary copper wire is that it >stretches. When I have used it I pre-stretch it before cutting it and >putting it up in the air. That's why I always do my level best to ensure that all my dipoles are supported from the CENTER, rather than being hung from the ENDS. This relieves virtually all of the stretching stress on the wires, and I can 'lift' the ends of the antenna without feeling I have to pull them tight within in inch of their lives. A little droop in the wires seems to not negatively effect the performance of dipoles. I get the center as high as possible and then lift the ends as high as practicable. Since the majority of the actual electromagnetic (radiating) field is concentrated from the feedpoint to about 50%-60% out to the ends, THIS is the part of the dipole I try to get as high as possible, and I don't worry too much abou tthe ends. Thus, little, if any, 'stretching' forces on the wires themselves. 73 - Tom Hammond N0SS +++++++++++++++++= Date: Mon, 01 Oct 2001 14:32:01 -0400 From: "David A. Belsley" Subject: Re: [Elecraft] antenna wire Tom: No, it's not coated. TheWireMan sells something they describe as FLEXWEAVE? 14 AWG 168 strand bare tinned ultra-flexible antenna wire. Highly corrosion resistant in reactive environments. It is their item number 549 under antenna wire. I've never used the stuff, and I have no idea how much it costs. best wishes, dave belsley, w1euy ++++++++++++++++++++ Date: Fri, 5 Oct 2001 22:38:30 -0400 (EDT) From: George Gingell To: QRP List Subject: [108143] Free (Almost) Antenna Wire Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Earlier, Uncle Brucie (W6TOY) mentioned use of #30 (Antother # was typed :^}, But the idea was to use Small Gauge Enameled wire for temporary or portable "No See 'em Antennas". By now everyone knows that an old TV yoke will yeild a nearly lifetime supply. #30 is a Good Choice. A Small Sinker and a length of Nylon Fishing line spliced to the end of the wire, a wrist rocket and you are in business. If you are in an area where a "Slingshot" is not allowed or desirable, Consider a Small rubber ball or even a Tennis Ball A Darning Needle and the Nylon Leader will skewer the ball and make for a good fastener. A small Dress Shirt Button will secure the Line to the ball. I thiink the tennis ball is ideal for Portable use as it has enough weight and is not likely to damage any Cars or Windows. Although they tend to be a bit curious hanging down the side of a tall building. :^} Another good source of very small gauage wire is in Telephone Relays or Solenoids. I have also used wire from a defective Telephone REceiver Unit. Some of the relay wire is about # 40. Wire Wrap Wire (Often available at Radio Shack) is generally #36 Guage. +++++++++++++++ Date: Sat, 6 Oct 2001 00:11:51 EDT From: KB9OCE at aol.com To: k3tks at u1.abs.net, qrp-l at lehigh.edu (Low Power Amateur Radio Discussion) Subject: [108151] Re: Free (Almost) Antenna Wire Message-ID: <41.11e5501f.28efde87 at aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Another source for small gauge durable wire is WalMart's closeout section. I picked up a 500 foot roll of wire for an invisible dog fence. Cost? $3. Since it's designed to be buried you know it has to be weather proof. 73 Mike +++++++++++++++++ Date: Wed, 3 Oct 2001 09:11:27 -0700 From: Vaclav Sal Subject: RE: [Elecraft] antenna wire How about "old fashioned" telephone drop wire? Twin steel copper clad, insulated. Have been using it for my 500 plus feet horizontal loop for over 8 years now. Definitely not a portable stuff! Little hard to work with - cuting with hacksaw is best. Does not tangle. Allegedly rodent resistant! I lost one support made from the same stuff to squirrels! The "new" four wire ( two pairs ) is only copper and no steeel. Have not used that for active element, just for support. Best of all - it was all FREE!!! PS. What do they use in Caribbean for telephone drops??? 73 Vaclav AA7EJ +++++++++++++++++ Date: Sun, 7 Oct 2001 10:57:16 -0400 From: "Francis Belliveau" Subject: Re: [Elecraft] Antenna Wire On: Monday, October 01, 2001 5:26 PM "Terry Kniffen" wrote: > For antennas exposed to the elements (or not), I have not heard or read much > about the difference between insulated wire and bare wire in terms of > physical or electrical properties. Is there a difference; and if not, why > not use insulated wire? > Okay so I am a bit behind in reading the mail. This one I had to respond to. Insulated wire alters the resonant length just a bit. This can easily be taken into account when trimming for resonance. However, if you are building one from plans this will make a difference just as using a different gauge wire will. I have had a dipole set for 80 and 40 in the air for about 10 years now. I live in Massachusetts so it has seem its share of snow and ice loads along with a fair quantity of solar radiation. The feedpoint is at least 50 feet up and it is made from 14 gauge solid insulated electrical wire. This may not be the best or most cost effective choice, but it was free wire. Bottom line is that if you are willing to trim things after they are together, then just use what you can find for wire. Copper is the best conductor that is practical for antenna use. Tom's concern about water intrusion by capillary action is real. The solution is to use something that will also be absorbed by capillary action while things are dry. I would suggest the thin crazy glue be applied after the ends have been trimmed and dressed to their final configuration. For sealing things against water intrusion, I have used two-part epoxies where things will not flex at all. Where I want a partially flexible seal I use low temperature hot melt glue. It holds up well and can be removed better that silicone caulk. However, the silicone is the only thing I have found that can handle points that are prone to significant flexing. Any suggestions along this line would be greatly appreciated. Just my experience with making antennas last. Good luck to all experimenters. Fran, KA4FRH ++++++++++++++++ Date: Fri, 15 Mar 2002 14:30:08 -0500 From: "Fancher, Mark (GEAE)" To: "'deni at gm3skn.fsnet.co.uk'" Cc: Low Power Amateur Radio Discussion Subject: [122176] RE: Wire Antenna materials your VIEWS? Deni, I can imagine that the Shetland environment could take a terrible toll on wire antenna materials! I live in Kentucky, so my environment isn't nearly as bad. Nevertheless, I did purchase some FLEXWEAVE(tm) wire from: http://www.thewireman.com/ It's great to work with, like working with rope. Its a bunch of fine strands woven together and its tinned for corrosion resistance. A little pricier, but much easier to work with and much more durable than solid wire. Mark, AA4MF -----Original Message----- From: DeniGm3skn [mailto:deni at gm3skn.fsnet.co.uk] Sent: Friday, March 15, 2002 2:22 PM To: Low Power Amateur Radio Discussion Subject: Wire Antenna materials your VIEWS? What is the current informed opinion on wire antenna materials? Wire and insulators? Solid copper versus stranded? 16 SWG copper. Covered or bare? If bare wire is used especially stranded does the inevitable corrosion on the copper strands cause any appreciable degradiation in perfomance? PVC or similar covering insulaton invariably fails somewhere and then of course water enters and unseen corrosion takes place! I wont even consider using any form of copperclad steel wires, bad experience with these! I have constructed many wire antennas in the past with whatever I had available but right now I want to fit and forget the 'Ultimate low loss Doublet' using the best materials I can get, it also has to be rugged to survive weather and wind. It's to be around 132' top with open wire line feed, probably home brew line as I hate that 450 ohm copper clad steel windowline stuff! Any comments or suggestions considered with much interest. 73, Deni, Gm3skn Shetland Islands UK ++++++++++++++++ From: Jim Eshleman To: deni at gm3skn.fsnet.co.uk Cc: Low Power Amateur Radio Discussion Subject: [122177] Re: Wire Antenna materials your VIEWS? Hi Deni, I like the #13 insulated copper-clad steel (19 strand, I think) that most vendors sell. I'm interested what bad experience you've had with copper-clad steel? 73 Jim N3VXI ++++++++++++++++ Date: Fri, 15 Mar 2002 13:55:03 -0600 From: Chuck Carpenter To: Mark.Fancher at ae.ge.com, qrp-l at lehigh.edu, deni at gm3skn.fsnet.co.uk Subject: [122179] RE: Wire Antenna materials your VIEWS? Deni, The Radio Works also lists Flexi-Weave" wire by Davis RF. #14 - 14 cents per foot, #12 - 17 cents per foot You indicated that you didn't want PVC insulated wire. RW offers this one with PE insulation. #14 168-strand PE insulated, 17 cents per foot. "Jacket is a tough quality .015 in. slick black polyethelyne. It's very tough. Perfect for heavy weather." You might consider latex house paint to cover and seal joints and connections. Chuck Carpenter, W5USJ, Point, Rains Co., TX - EM22cv, NETXQRP #1 QRP-ARCI #5422, QRP-L #1306, SOC #57, 6 Club #201, SMIRK #6275 Zombie #759, QRPp-I #115, COG #11, NETXQRP http://www.netxqrp.org +++++++++++++++ Date: Fri, 15 Mar 2002 19:54:29 -0000 From: "DeniGm3skn" To: "Jim Eshleman" Cc: "Low Power Amateur Radio Discussion" Subject: [122180] Re: Wire Antenna materials your VIEWS? ----- Original Message ----- From: "Jim Eshleman" > Hi Deni, > > I like the #13 insulated copper-clad steel (19 strand, I think) that > most vendors sell. I'm interested what bad experience you've had with > copper-clad steel? > > 73 > Jim N3VXI Jim to expand, my bad experiences with copperclad steel wire is confined to the use of use of 450 ohm windowline. This stuff has something like 22SWG solid wire copperclad steel conductors , the copper inevitably cracks or fails in some way and the steel rusts!! who need a rusty feed line it's awful stuff! Not to mention all the trouble with breakages it's far too brittle. I guess your antenna wire is much more substantial and robust but I dont like steel in my wires :) 73 Deni...Gm3skn ++++++++++++++++++++ Date: Fri, 15 Mar 2002 16:52:11 -0500 From: Dave Fouchey To: deni at gm3skn.fsnet.co.uk, Low Power Amateur Radio Discussion Subject: [122184] Re: Wire Antenna materials your VIEWS? Well being blessed with a fairly large supply of solid #9 hard drawn insulated wire designated for outside installations I use it for antenna work. Not very good for portable antennas but great for LF and MF dipoles with minimal sag... Using copper clad steel for open wire transmission lines on poles I have had numerous occasions in coastal environments where the slightest nick in the cladding lead to the steel core rusting out and breaking at the least opportune moments. I much prefer hard drawn solid copper, I use #9, for antenna work. 73's Dave WA4EMR ++++++++++++++++++ Date: Fri, 15 Mar 2002 17:27:17 -0500 From: W2AGN To: Chuck Carpenter , Low Power Amateur Radio Discussion Subject: [122186] Re: Wire Antenna materials your VIEWS? On Friday 15 March 2002 14:55, Chuck Carpenter wrote: > Deni, > > The Radio Works also lists Flexi-Weave" wire by Davis RF. > > #14 - 14 cents per foot, #12 - 17 cents per foot > -- I made my 40M dipole with this stuff. In 2 years, it broke 3 times. Just finished replacing it with Copperweld! My 300' loop is made with copperweld, and at least 180' of it has been up for 15 years! -------------------------- John L Sielke W2AGN w2agn at pobox.com http://mywebpages.comcast.net/w2agn Trustee: W3IYQ +++++++++++++++++ Date: Sat, 16 Mar 2002 09:20:44 -0500 From: Jim Eshleman To: jce0 at Lehigh.EDU Cc: Low Power Amateur Radio Discussion Subject: [122223] Re: Wire Antenna materials your VIEWS? > I like the #13 insulated copper-clad steel (19 strand, I think) that > most vendors sell. Duh. I should say why I like it. - It is said (somewhere) that insulated wire is quieter vs. bare wire that has become oxidized/pitted/corroded/whatever. - This wire is insulated w/black low-gloss PE coating, which is somewhat stealthly and very tough. - Copper-clad steel (CCS) is 2.5 times as strong as hard-drawn copper. See the table in the ARRL Antenna Book (and maybe the Handbook) where #14 CCS has a recommended tension of 50lbs and hard-drawn copper 20lbs. The recommended tension is one-tenth of the breaking load. - I didn't like the idea of 168/259/whatever very small strands of copper in the Flex-Weave. Seemed to me that the stands would break easily if stressed frequently. - In my experience CCS stretches much less than hard-drawn copper. - In my experience the PE coating has not hardened and chipped-off. My experience is limited to a 40M dipole strung between to 35-40ft pine trees, no pulleys or counterweights, and RG58 hanging from the center, so it gets well-stressed when the wind howls. And don't forget the PA acid-rain which hasn't affected the PE coating that I can tell. This antenna has been up about 4 years. YMMV of course... 73 Jim N3VXI ++++++++++++++++++++ Date: Sat, 16 Mar 2002 09:32:10 -0700 From: "James R. Duffey" To: qrp-l Subject: [122239] Antenna Wire Wire serves two purposes in an antenna system; one electrical and one structural. Electrically, the driving requirement is good conductivity. This requirement, plus the secondary one of cost, usually drives us to use copper as the material of choice. Smaller (numerically) gauge wire has higher conductivity and larger gauge (numerically) wire has lower conductivity. In general any gauge of copper wire that will stay in the air will have adequate conductivity for an antenna, even that 30 gauge used for hidden antennas. Structurally, there are a number of driving parameters. Strength enough to support the antenna. flexibility enough to not work harden, and resistance to corrosion all drive the choice of antenna wire from a structural point. As a side note, the National Building Code calls out 14 gauge hard drawn wire as the minimum size to be used for antennas. Believe it or not, Radio Shack sells good practical antenna wire. A 70 foot roll of 14 gauge (7 strands of 22 gauge) hard drawn copper wire costs $7.00 here. At $0.10 a foot, the price is reasonable, although not cheap. I use this wire a lot, largely because of its wide avaialbility. I don't have any problems here in New Mexico with it. However in an environemnt that is more corrosive, like near the ocean or in a large city, one quickly finds that stranded wire has its problems. The stranded wire quickly oxidizes or sulfidizes (is that a chemical term?). If there are few strands, like in the Radio Shack wire, this doesn't cause much of a problem until you try to repair an antenna. Then you find that the corrsion has reached down in the wire between the stransds, and soldering is impossible unless you etch the copper with a mild acid like lemon juice or a commercial polish like Tarn-X. This should be followed by a baking soda rinse to neutralize the acid. This doesn't sound too bad, but doing it on your roof on a windy day is no easy trick. "What is dad doing on the roof with your lemon juice, Mom? If the strands are very small, like in the flexweave type wire, corrosion can eat entirely through the small strands and bring the antenna down. Copperweld or Copper Clad steel is good antenna wire if it is the real stuff. Some lightly plated steel wire is sold, but it quickly corrodes. Price can be your guide here. The problem with Copperweld is that it is stiff and hard to handle, If you nick the copper through to the steel core, the steel core will rust. I have used soft drawn copper magnet wire for antennas, largely because I received 100s of feet of it as a gift. This makes an acceptable antenna, but the soft drawn wire will stretch over time. Thus it is not too good for resonant dipoles as the resonant frequency will change over time, but if you use an antenna tuner you probably won't notice it. The stretch is less of a problem with an antenna erected as an inverted vee. You can remove most of the stretch before erecting the antenna by securely fastening one end of it and giving a quick hard jerk to the other end. Expect a change in length of a foot or two and strange stares from the neighbors. If you jerk too hard it will break. THHN House wire, stranded or solid, is widely avaialble cheap at home supply stores. It works fine for antennas, although the insulation tends to crack and peel after a few years, at least in my climate. But the electrical performance is largely unchanged. I have also used 22 gauge PBX wire (insulated) for antennas. I have thousands of feet of this that I rescued from a dumpster when the building I was working in was remodeled. It works fine, but hte insulation changes color upon exposure to the sun. The insluated wires are larger diameter than the equivalent bare wire, and this can be a problem if you have icing. I have heard of the use of Teflon insulated wire to alleviate icing, but have not tried it myself. Insulated wire works just as good for antennas as does bare wire. Often we hear the refrain in conjunction that the antenna was " I cut it per the formula in the handbook, but it resonated at a different frequency". Well, the formula in the handbook is not gospel and was determined experimentally. It is shorter than a half wave in free space due to capacitive loading at the ends. This loading will vary according to the antenna's environment, configuration, and end insulators used. So you should expect it not to resonate exactly at the frequency you cut it for. This is a long post, but the long and short of it is that pretty much any copper wire will work for an antenna. - Dr. Megacycle KK6MC/5 -- James R. Duffey KK6MC/5 Cedar Crest, NM DM65 ++++++++++++++++ Date: Sat, 16 Mar 2002 12:36:57 EST From: W2SH at aol.com To: qrp-l at lehigh.edu Subject: [122244] Re: Wire Antenna materials your VIEWS? (Long) In my antennas and my feedlines I DO NOT LIKE: 1. Magnetic materials, e.g., steel. I have experienced rf losses when using steel, and stainless steel as well,=20 for conductors of rf. My steel losses increase when standing waves are=20 present. I first experienced this 30 years ago when trying to match 50-Ohm=20 coax to the high impedance end of an extended double zepp with a=20 quarter-wave, closed stub made of no. 8-gauge, galvanized steel fence wire.=20= =20 My signal reports from all stations in a local net stank. They improved a=20 good bit when I used 14-gauge, solid copper wire for the stub. 12 years ago= =20 I noted that Moxon's wonderful book made a couple of references to the=20 deleterious effects of magnetic substances in antennas. I only wish that he= =20 had stressed this point more than he did. I also avoid copper clad steel because, despite the best insulations,=20 moisture seems to get in through the slightest crack or abrasion. =20 Eventually, through just a single tiny nick in the copper, corrosion works=20 its way to the steel core, and very soon after that, the steel rusts and=20 breaks. For a long time I really liked that 13-gauge, 19 strand,=20 polyethylene jacketed wire. Although difficult to grip with one's bare=20 hands, it had many fine mechanical qualities. However, when my 540-footer=20 came down, a post mortem showed corrosion, not green but black, a=20 surprisingly long distance from the break point. 2. ANY stranded wire where the strands are bare. "The resistance [and here it is rf, not dc resistance which is being treated= ]=20 ratio of n strands of bare wire placed parallel and making contact with one=20 another is found by experiment to be the same as for a round solid which has= =20 the same area of cross section as the sum of the cross-sectional areas of th= e=20 strands; that is, n, times the cross section of a single strand. This will=20 be essentially the case in conductors that are in contact and are poorly=20 insulated, except that at high frequencies the additional loss of energy due= =20 to heating of the imperfect contacts by the passage of the current from one=20 strand to another may raise the resistance still higher." =20 Hey, guys, read that quotation through a couple of times. Stranded wire is=20 fine to power up your desk lamp with 60Hz soup, but not good at "high=20 frequencies." New stuff? Heck, no! That was published in a 300-page book=20 by the US Bureau of Standards back in 1918. If you're not sufficiently OT,=20 an article on these matters appeared in QEX a bit over a year ago. =20 Personally, I also think that the spiral configuration of twisted strands,=20 when they are in imperfect contact with one another, introduces an inductive= =20 effect which further increases the losses. Given the ease with which corrosion manages to penetrate insulations, it=20 isn't hard to see why the degradation of the rf conductivity of even pure=20 copper stranded wire will occur. And if you use stranded copper-clad steel,= =20 you can add in magnetic losses. 3. Bare solid pure copper wire. Obviously, conductivity losses will occur when bare wire touches wet tree=20 limbs, or whatever else. Unlike the stranded wire case, I don't (yet) believe corrosion on the outer=20 surface of bare solid copper wire too harmful. And remember that corrosion= =20 can get easily inside thick insulations and poor quality thin insulations (m= y=20 definitions of "thick" and "thin" appear below). I tend to look at the=20 corrosion as a layer of semiconductive stuff, part way between being a=20 conductor and an insulator. In truth, my feeling is that if the corrosion i= s=20 more an insulator, that's OK, but if it's more of a conductor (and its=20 conductivity is bound to be less than that of pure copper), then that's bad,= =20 as no. 4 below describes . =20 An excellent reason to have the antenna and feedline conductors insulated is= =20 to lower received noise. The source of noise I'm referring to is called rai= n=20 or snow static. Raindrops and snowflakes falling through the sky do not=20 enjoy a frictionless descent. Rather, these particles of moisture develop a= =20 small electrostatic charge which is discharged when they strike a conductive= =20 surface. I would suspect that there is even a small capacitive discharge=20 when they encounter an insulated conductor, but that it is very much less=20 than for a bare conductor. (On the other hand, lots of static in a pair of=20 headphones might dislodge ear wax). 4. Solid copper wire which is plated. Platings of tin, lead, antimony, or whatever else might improve copper wire'= s=20 solderability, all reduce the surface (and that's where skin effect makes it= =20 important to pay attention when dealing with high frequency rf) conductivity= .=20 =20 Over the past 70 or so years, copper smelting and refining has improved to=20 the point where the metal's conductivity has increased. On the other hand,=20 the purity of silver once used to improve the conductivity of poorly smelted= =20 copper has been reduced over perhaps the past 60 years to the point where=20 "silver"-plated wire most likely has less conductivity than the copper=20 underneath. Gold, which does not tarnish, might be a beneficial plating on copper if its= =20 retardation of corrosion were to more than offset its approximately=20 50-percent lowering of the surface conductivity of the copper underneath. I= n=20 any case, using thin insulating coatings, or, better yet, combined thin and=20 thick insulations, is, I would think, a cheaper way to preserve the=20 conductive integrity of copper wire. 5. Solid copper wire with thick insulation. For me, thick insulation means any sheathing whose radius is greater than,=20 say, 10 percent of the conductor's diameter. Any insulation which is thick will reduce the velocity factor of even a=20 single conductor of rf. The thicker the insulation sheath becomes, the lowe= r=20 the velocity factor, and the greater the losses, especially when standing=20 waves are present. For a given radiator length, the lower the velocity=20 factor, the lower the resonant frequency of the radiator. Slip a hot dog on= =20 your 440-mHz quarter-wave whip, and you'll be illegally QRP below the low en= d=20 of the band. (Might be a good way to cook the beast, though). PVC is quite plastic. It adds considerable weight to the wire, but almost n= o=20 strength and not much abrasion resistance. Fabric coverings seem to have=20 disappeared with the advent of "plastic." Polyethylene, especially when it=20 has an additional nylon jacket, is about the best thick insulation I've=20 encountered in terms of its abrasion resistance. Teflon's wonderful=20 insulating qualities aren't needed, and certainly don't justify its high cos= t=20 if the antenna is properly free and clear of foreign objects. 6. Solid copper wire with thin insulation. "Enameled" (a generally applied term) wire is not specifically manufactured=20 for antennas. Rather, it is designed, almost exclusively, for winding the=20 armatures and field coils of electric motors and generators. Here what is=20 needed is an insulation which will not crack when wound with a small radius,= =20 whose abrasion resistance is such that it will withstand being rubbed by=20 adjacent turns during the winding process, and, frequently, it must withstan= d=20 high temperatures. Obviously, enamel insulation is not designed for being=20 stretched over long straight runs, dragged over tree branches, nor to resist= =20 acid rain, bird droppings, and especially, the sun's ultraviolet radiation.=20= =20 Some enamel insulations work much better outdoors than others. It is hard t= o=20 know which are the good ones, but in my experience, they are few and=20 invariably very expensive. =20 You may conclude that I dislike everything having to do with antenna=20 materials, but my distastes vary enormously. In my perfect world, my (truly= )=20 open-wire feedlines, would never be under tension and never drape across=20 foreign objects. This would allow me to have no. 12 or 14-gauge, solid, sof= t=20 (hard-drawn copper has a tiny bit less conductivity than soft copper) wire,=20 with a perfect(!) thin (and therefore light-weight) insulation. For=20 feedlines, my perfect world can pretty much be realized. Alas, I like big antennas. Here strength considerations become very=20 important, as does abrasion resistance because my big antenna rubs against=20 tree branches when the wind blows hard . One recent and quite worthy=20 suggestion called for 9-gauge copper wire. I don't know if it was solid or=20 stranded, nor what, if any, insulation it carried. I do know that it would=20 not stretch very much, but it would certainly be too heavy for my yet-to-be=20 resurrected 540 footer. Again, in my perfect world, I would like a no.12 or 14-gauge, solid copper=20 conductor. I need thick insulation for abrasion resistance, plus thin=20 insulation underneath for corrosion resistance. I very much doubt that such= =20 wire is manufactured, and I am unable to homebrew it. More importantly, I=20 want it to not stretch, be strong, be flexible and not weigh too much. =20 Having all these qualities simultaneously seems to me to be impossible. Therefore, I have decided to not worry about the corrosion if it occurs. I=20 plan to use no.12-gauge, solid copper wire with the best thick insulation I=20 can find. [ For 160, 80, and, maybe some day, 60 meters, I'd use instead a=20 husky litzendraht wire, whose individual strands are always insulated, with=20= a=20 thick outer jacket. This stuff only exists in my dreams]. I intend to spiral it loosely (no more than one turn per meter) on=20 wax-impregnated, 3/16"-diameter Kevlar-cored rope having a braided-polyester= =20 Dacron jacket. I will affix the wire to the rope with widely spaced ties=20 made from 75-lb test, braided Dacron kite line and a thin coating of the bes= t=20 silicone caulk I can obtain. I will work long and hard and not be=20 discouraged when Murphy strikes. (I will not even think about antennas this= =20 coming Sunday--March 17th). The above shows my dislikes, aspirations and intended, but compromised,=20 approach. I'm not going to waste time trying to prove any of the above=20 assertions, and anyway I'm probably not qualified to do so. Yet I welcome=20 all comments and suggestions. I need all the help I can get. May these=20 contain light, not heat, but just in case=E2=80=A6 "Hey, Maw, start puttin' rations in the foxhole, 'cause thar's goin' to be=20 incomin' from QRP-L. And load up ma' Flit gun with a pint of kerosene. Now= =20 lemme see, where did I hang up them danged itchy asbestos BVDs=E2=80=A6" Charles, W2SH ++++++++++++++++++ Date: Sat, 16 Mar 2002 11:07:47 -0700 From: "Francis Callahan" To: , "Low Power Amateur Radio Discussion" Subject: [122246] Re: Antenna Wire I have used 12-3 house wire for almost 25 years just strip the outer casing off and you have 3 wires so you only have to buy 1/3 rd of what you need and it will last for years and years if you leave the plastic coating on . Just streatch it out a bit before putting up 72 Cal KF7ET misplaced Vermonter in Idaho ++++++++++++++++++ Date: Sat, 16 Mar 2002 13:42:11 -0500 From: Dave Fouchey To: W2SH at aol.com, Low Power Amateur Radio Discussion Subject: [122251] Re: Wire Antenna materials your VIEWS? (Long) At 12:36 PM 3/16/2002 -0500, W2SH at aol.com wrote: > >Alas, I like big antennas. Here strength considerations become very=20 >important, as does abrasion resistance because my big antenna rubs against= =20 >tree branches when the wind blows hard . One recent and quite worthy=20 >suggestion called for 9-gauge copper wire. I don't know if it was solid or= =20 >stranded, nor what, if any, insulation it carried. I do know that it would= =20 >not stretch very much, but it would certainly be too heavy for my yet-to-be= =20 >resurrected 540 footer. > Solid Hard Drawn #9 with a thick weather resistant poly insulation. Used specifically for open wire transmission lines/telephone circuits. The stuff is tough, strong, and makes great wire antennas. At HF the change in vf of the wire is minimal. Noise from snow and rain is lowered due to the insulation. I have strung miles and miles of this for telephone work on the Railroad. Yes it is heavy, a minor trade off in exchange for it's strength and durability. It IS harder to work with than smaller gauge wire, but it is a trade I am more than happy to live with for it's ability to stand up to icing and high winds. Have also used #9 Copperweld and in the coastal environs we were using it, it was more trouble than it was worth. Initially stronger then the HD Copper, it was subject to core corrosion through even the most minor nick in the cladding. -- snip -- Happy constructing Charles! 73's Dave WA4EMR +++++++++++++++ Date: Sun, 17 Mar 2002 08:43:36 -0500 From: Parker Buckley To: unlisted-recipients:; (no To-header on input) Cc: Low Power Amateur Radio Discussion Subject: [122323] Re: Wire Antenna materials your VIEWS? I've had some experience with The Wireman Silky, #16, with my quad. Great stuff to work with when new, but after one year up, it's oxidized and I found that I can no longer solder to it without acid core solder, and after two years up, it's badly corroded, brittle, and shredding. Maybe the plastic coated version would be okay, but I don't think the bare version is a good investment. QTH is in Springfield OH, with probably typical midwest air pollution. Parker WD8JOL DeniGm3skn wrote: > What is the current informed opinion on wire antenna materials? Wire and > insulators? +++++++++++++++++++++ Date: Fri, 22 Mar 2002 15:33:33 -0500 From: George Reeves To: QRP-L Subject: [122944] THHN House wire! Message-ID: <3C9B951C.52EBDCC7 at emory.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I answered my own question by finding the following document: http://www.solenergy.org/pdf/PV301/WireRatings.pdf George WA4TNU +++++++++++++++++++++