Sorry to hear about your antennas, been there this
year as well. A couple of suggestions that I've had some experience with: Flex Weave wire is very nice to work with and it's quite tough, not particularly cheap, but definitely easier to work with than copperweld. It's coated and I've had branches fall on it without any damage. Another option is old RG58 coax (RG8X, RG59 also, RG8 is heavy and might be too heavy under 30M) I connect the outer braid to the inner conductor on both ends. It's lighter and has a larger diameter, cut it a little shorter (2 to 5%) than the bare wire formulas. Good Luck! Julius n2wn _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Julius Fazekas
N2WN Tennessee Contest Group http://www.k4ro.net/tcg/index.html Tennessee QSO Party http://www.tnqp.org/ Elecraft K2 #4455 Elecraft K3/100 #366 Elecraft K3/100 |
We did this on a mountaintop in the middle nowhere, so there
was no one around to get hurt but us. We tried to use a slow, constant tension, and pulled it until it broke. David had done this before and showed me what hard drawn copper sounds like (rather "springy"), and declared it "good." There is some "backlash" when the wire breaks (but not a lot) so it is a good idea to observe reasonable caution when doing this. I would advise doing this with two people -- one to drive and one to observe. Don't expect a lot of stretch -- 5-10% is enough. And if we didn't have David's SUV, I would have just as readily done it with my Volvo. Jim Brown K9YC On Wed, 8 Sep 2004 18:03:18 +1200, Paul Saville wrote: >Thanks for the information Jim. I've had some copper clad up for about 2 years and it's still working OK, but time will tell. > >I was given a big roll of #8 solid copper a while ago, and >thought about stretching it with my car, but was worried about >the mess it would make if the wire broke! Did you put a >constant tension on it with the SUV or let it boucne back like a >rubber band? Might give it a try, but will lock the kids in the >house first! > >73 Paul ZL3IN > >> And the cladding disappears after a few years according >> to what I hear. >> >> The real deal if you want strength AND good electrical >> performance is hard drawn copper. >> We needed some for W6BX, so I went to Home Depot and >> bought a 500 ft spool of #8 solid copper (about $50). >> David, WA6NMF, hooked one end to a power pole, the >> other to his SUV, and in five minutes we had 10% more >> hard drawn copper than we bought, and one half wire >> gauge smaller (8.5?). It is FAR easier to handle than >> copperweld, it is strong, it won't rust, the copper >> cladding won't fall off, the resistivity is quite low, >> you can easilly solder to it, and it is CHEAP! >> Oh yeah -- figure the weight of copperweld and the >> weight of hard drawn copper and there isn't a lot of >> difference. > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
In reply to this post by Julius Fazekas n2wn
In a message dated 9/8/2004 5:40:06 AM Eastern Daylight Time, Charles Greene <[hidden email]> writes:
>If you live near enough sea water to get an >occasional sea spray, the >copperweld copper clAdding will corrode green, >then the core will rust in >several places. After that the wire breaks if >flexed like. It doesn't require salt spray to do that, either. Just takes longer. What happens is that *any* break in the copper cladding can let in moisture, and set up an electrolytic corrosion situation. The steel core corrodes like mad because it's essentially the cathode in a copper-steel cell whose plates are shorted. Of course salt water makes a better electrolyte than rain water, but any sort of ions in the water help things along. Pretty soon you have a piece of copper tubing and the wire fails. There are different levels of copper cladding, too - some are much thicker than others. There are also versions with insulation, which tends to protect the wire everywhere except joints. Joints can be protected by Plumbers Goop or similar noncorrosive sealer. Some folks swear by copperclad, others swear at it, but it *is* the strongest stuff for a given gauge. In the end, a lot depends on your replacement philosophy. Some folks replace before it falls down, others after... 73 de Jim, N2EY I didn't used to believe all the stuff about acid rain and UV exposure until I saw what my wire antenna hardware looked like after 5 years aloft. Not pretty! _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Time for just a short note -
I have used nothing but copperweld for antenna wire for 40 years, never had a span fail due to corrosion, or for that matter, for any other reason. And, I have always lived in coastal communities. I normally use #12 AWG wire for antennas, #16 AWG for things like open wire feeders (I make my own lines). I agree that there are different quality levels for this wire. The brand I use is Crown Metals, and it has never let me down. As a side note, when I worked for the phone company up this way, we had some open wire spans for telephone service (both direct and carrier). These spans survived harsh Alaskan winters for more than 50 years. They normally used #10 AWG for "regular" spans of up to 250 feet between poles, and #8 AWG for long spans, up to 500 feet. Crown metals brand products are available from AES, the last time I looked, and probably from most of the other vendors of antenna parts you see in QST. Yes, copper clad wire gets an outer layer of copper oxide, but there seems to be no degradation of performance. I dislike insulated wire because water can creep inside the insulation, and that can be bad news for any antenna. Using house wire is not a good idea, as it is not very strong for its weight, and it is carrying the added load of plastic insulation. Stretching regular wire about 10% will harden it considerably, but this only approximates "real" hard drawn wire - which does not stretch appreciably. Also, there is no rule that says you have to use copper. Aluminum electric fence wire works well, but you have to remember to use an anti-corrosive coating at the joints. A typical product is "Noalox". Fence wire is light weight, inexpensive, and quite strong per unit of length. Try to find 14 or even 12 gauge if you can, but smaller sized work for most uses. Larger diameters are better both from a strength perspective and have less ohmic losses. However, in a pinch, any size is better than none. For low power work, I often use 24 gauge magnet wire for temporary antennas, and it always performs well electrically, even if it has trouble surviving storms. Here's a hint for making your own open wire feeders: For spreaders, I use a plastic material sometimes called "UHMW" (stands for Ultra High Molecular Weight, I am told). This is a black UV stabilized material that is nearly indestructible. I get it in 1/2" thickness, and use my standard wood bandsaw to cut it into strips about 1/2" square by 5" long. Drill a couple of 1/8" holes about 1/2" in from each end, and attach the insulators to your feedline with tie wires, spacing then no closer than 3 or 4 feet. 25 of these spreader insulator thus make a 100 foot open wire feeder. Use #16 AWG copperweld for the feeders, #18 for the tie wires. Solder each tie wire to the main feeder wire. BTW - the tie wires go through the holes, not the feeders I have had such a feeder up for 30 years, and it has never failed. It will also take any (legal) level of power you care to use. There is no significant heating or other distress at 1500 watts CW, even when working with high VSWR (8:1 mismatch or more), and in rain or snow. The plastic can often be obtained from your local vendor of plastic products as "cutoffs" for significantly reduced prices. The material is commonly used for sled runners, boat fenders, dock fenders, and so on. UHMW is also suitable for end insulators, Cut a length about 8" to 10" long by 1" wide (from the same 1/2" thick material), drill a 1/4" hole about 1" in from each end, and you're good to go. Such an insulator held a 700 lb test load without difficulty. It might have held more, but the wire I was using to support the weights broke. Good luck, and 73 Jim, KL7CC [hidden email] wrote: >In a message dated 9/8/2004 5:40:06 AM Eastern Daylight Time, Charles Greene <[hidden email]> writes: > > > >>If you live near enough sea water to get an >occasional sea spray, the >>copperweld copper clAdding will corrode green, >then the core will rust in >>several places. After that the wire breaks if >flexed like. >> >> > >It doesn't require salt spray to do that, either. Just takes longer. > >What happens is that *any* break in the copper cladding can let in moisture, and set up an electrolytic corrosion situation. The steel core corrodes like mad because it's essentially the cathode in a copper-steel cell whose plates are shorted. Of course salt water makes a better electrolyte than rain water, but any sort of ions in the water help things along. > >Pretty soon you have a piece of copper tubing and the wire fails. > >There are different levels of copper cladding, too - some are much thicker than others. There are also versions with insulation, which tends to protect the wire everywhere except joints. Joints can be protected by Plumbers Goop or similar noncorrosive sealer. > >Some folks swear by copperclad, others swear at it, but it *is* the strongest stuff for a given gauge. > >In the end, a lot depends on your replacement philosophy. Some folks replace before it falls down, others after... > >73 de Jim, N2EY > >I didn't used to believe all the stuff about acid rain and UV exposure until I saw what my wire antenna hardware looked like after 5 years aloft. Not pretty! >_______________________________________________ >Elecraft mailing list >Post to: [hidden email] >You must be a subscriber to post to the list. >Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft >Help: http://mailman.qth.net/subscribers.htm >Elecraft web page: http://www.elecraft.com > > > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
A foot note to Jim's wire comments: Watch out for fence wire that is
Aluminum clad steel. It will be less ductile than true aluminum and will quickly rust out and fail where scratched or nicked. Sadly, copper plated steel fence wire sold for electric fences, rusts out in about a year in humid climates. 73, Stuart K5KVH _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
I wanted to let the list know that there was a problem in QRP Radio
Comparison Chart in my QRP Community column. http://www.arrl.org/news/features/2004/09/08/1/?nc=1 The row for "Keying method" was accidently color coded incorrectly . Hope fully ARRL will be able to fix tomorrow. Correct color coding for the row should be: K2- Green /// IC-703- Red /// Argonaut- Green /// FT-817- Red. Sorry for the error, I am a very happy owner of a K2 and it definitely gets the most use of all four radios when I operate CW HF from my shack. _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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