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#11
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Reg, was that 30 meters and 90 feet or 60 feet and 20 meters? Just
for us mathematically challenged. W4ZCB =================================== Harrold, To be exact, 30 meters = 98.43 feet. It was NOT a deliberate mistake to check on how much interest would be displayed in the experiment by readers. But it could have been. ;o) I did swap the connections between antenna and counterpoise and, as you can guess, it didn't make a scrap of difference. The underground antenna ended up in a bunch of other radials. But the best radial I have is the incoming domestic water main which is terminated at its other end by 100,000 miles of underground pipes feeding the whole of the Black Country (where it all began) and the Great City of Birmingham (which yesterday suffered a tornado due to Earth warming climatic changes caused by American pollution of the atmosphere). It was only the day before that life in the city was disrupted by police raids on houses alleged to be occupied by unsuccessful suicide bombers. Birmingham, in opposition to Manchester, will do anything to get into the news! ---- Reg. |
#12
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In message , Reg
Edwards writes Reg, was that 30 meters and 90 feet or 60 feet and 20 meters? Just for us mathematically challenged. W4ZCB =================================== Harrold, To be exact, 30 meters = 98.43 feet. It was NOT a deliberate mistake to check on how much interest would be displayed in the experiment by readers. But it could have been. ;o) I did swap the connections between antenna and counterpoise and, as you can guess, it didn't make a scrap of difference. The underground antenna ended up in a bunch of other radials. But the best radial I have is the incoming domestic water main which is terminated at its other end by 100,000 miles of underground pipes feeding the whole of the Black Country (where it all began) and the Great City of Birmingham (which yesterday suffered a tornado due to Earth warming climatic changes caused by American pollution of the atmosphere). It was only the day before that life in the city was disrupted by police raids on houses alleged to be occupied by unsuccessful suicide bombers. Birmingham, in opposition to Manchester, will do anything to get into the news! It has to. Mike |
#13
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I've used an antenna made of buried radial wires for many years, with a
vertical counterpoise, and AM broadcasters have been using this technique for the better part of a century. Works fine. Hm, maybe I should add another column to the wire specification table in EZNEC so people can specify whether the wire is an (A)ntenna or (C)ounterpoise. . . A related antenna was described many years ago in one of the amateur magazines. The author explained that when we construct a vertical antenna, an image antenna appears in the ground. So he simply dug a hole in the ground in put his vertical below ground. The image antenna did the radiating, of course. I did a pretty thorough search of QST and couldn't find the article -- I'd be indebted to anyone who can recall where this appeared. My guess is that it was around the early '60s. In an April issue of course. Roy Lewallen, W7EL Reg Edwards wrote: Some years back I buried a 30 metre (60-feet) auminium wire one spade depth in my back garden. Wire was 1.5 mm in diameter. Soil resistivity about 100 ohm-metres. To scientists that's 10 milli-Siemens. The near end of the wire came up in the shack. That's under my kitchen sink. It's still there. Open-circuit at the far end. As a counterpoise, something essential to tune it against, I erected a wire in the form of an inverted-L. This was about 30 feet high and overall length about 140 feet. I chose this length because it fitted nicely into my back garden. The front garden is too short even for an underground antenna. On the 160m band I fed into it about 30 watts from a home-brew transceiver so I can't provide for the record a manufacturer's type and serial number. However I still have the transceiver which can be inspected. Despite a high local noise level of S-6 I was able to communicate up to 60 miles with mobile stations in broad daylight on SSB. After sunset I could easily communicate with most of Europe on CW. I think a record of these buried antenna experiments should be kept for posterity, alongside the famous biblical work of B,L & E. By the way, as you see, I did remember to measure soil resistivity. It was the first thing I did. What buried wire do you think I used to measure it? ---- Reg, G4FGQ |
#14
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I agree that it was an April issue and I think my old friend W8DMR
(Bill) may have written it. However, I was thinking it more in the mid 60's. de W8CCW On Fri, 29 Jul 2005 12:51:56 -0700, Roy Lewallen wrote: I've used an antenna made of buried radial wires for many years, with a vertical counterpoise, and AM broadcasters have been using this technique for the better part of a century. Works fine. Hm, maybe I should add another column to the wire specification table in EZNEC so people can specify whether the wire is an (A)ntenna or (C)ounterpoise. . . A related antenna was described many years ago in one of the amateur magazines. The author explained that when we construct a vertical antenna, an image antenna appears in the ground. So he simply dug a hole in the ground in put his vertical below ground. The image antenna did the radiating, of course. I did a pretty thorough search of QST and couldn't find the article -- I'd be indebted to anyone who can recall where this appeared. My guess is that it was around the early '60s. In an April issue of course. Roy Lewallen, W7EL Reg Edwards wrote: Some years back I buried a 30 metre (60-feet) auminium wire one spade depth in my back garden. Wire was 1.5 mm in diameter. Soil resistivity about 100 ohm-metres. To scientists that's 10 milli-Siemens. The near end of the wire came up in the shack. That's under my kitchen sink. It's still there. Open-circuit at the far end. As a counterpoise, something essential to tune it against, I erected a wire in the form of an inverted-L. This was about 30 feet high and overall length about 140 feet. I chose this length because it fitted nicely into my back garden. The front garden is too short even for an underground antenna. On the 160m band I fed into it about 30 watts from a home-brew transceiver so I can't provide for the record a manufacturer's type and serial number. However I still have the transceiver which can be inspected. Despite a high local noise level of S-6 I was able to communicate up to 60 miles with mobile stations in broad daylight on SSB. After sunset I could easily communicate with most of Europe on CW. I think a record of these buried antenna experiments should be kept for posterity, alongside the famous biblical work of B,L & E. By the way, as you see, I did remember to measure soil resistivity. It was the first thing I did. What buried wire do you think I used to measure it? ---- Reg, G4FGQ |
#15
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Reg:
I can't even dream of burying a perfectly good, working, beautiful, sleek antenna! .... I shall refrain from burying any antenna, before its' time ... John "Reg Edwards" wrote in message ... Some years back I buried a 30 metre (60-feet) auminium wire one spade depth in my back garden. Wire was 1.5 mm in diameter. Soil resistivity about 100 ohm-metres. To scientists that's 10 milli-Siemens. The near end of the wire came up in the shack. That's under my kitchen sink. It's still there. Open-circuit at the far end. As a counterpoise, something essential to tune it against, I erected a wire in the form of an inverted-L. This was about 30 feet high and overall length about 140 feet. I chose this length because it fitted nicely into my back garden. The front garden is too short even for an underground antenna. On the 160m band I fed into it about 30 watts from a home-brew transceiver so I can't provide for the record a manufacturer's type and serial number. However I still have the transceiver which can be inspected. Despite a high local noise level of S-6 I was able to communicate up to 60 miles with mobile stations in broad daylight on SSB. After sunset I could easily communicate with most of Europe on CW. I think a record of these buried antenna experiments should be kept for posterity, alongside the famous biblical work of B,L & E. By the way, as you see, I did remember to measure soil resistivity. It was the first thing I did. What buried wire do you think I used to measure it? ---- Reg, G4FGQ |
#16
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My brother quit the power company when they were switching to "underground
utilities" - he got tired of burying those telephone poles so deep! And I had to give up chicken farming because the county extension agent said I was planting them too deep - I think I must have been planting them too near the underground power lines. "John Smith" wrote in message ... Reg: I can't even dream of burying a perfectly good, working, beautiful, sleek antenna! ... I shall refrain from burying any antenna, before its' time ... John |
#17
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Sometimes it works if you unplug it, turn the plug 180 degrees, and plug it
back in. ground loops get hairy sometimes. |
#18
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wrote:
Reg Edwards wrote: Some years back I buried a 30 metre (60-feet) auminium wire... Hi Reg, Interesting, but isn't a 30 metre wire more like 100 feet instead of 60 feet? ... Perhaps Reg took into account a velocity factor for sub-ground aluminum wire? Irv VE6BP :-) -- -------------------------------------- Diagnosed Type II Diabetes March 5 2001 Beating it with diet and exercise! 297/215/210 (to be revised lower) 58"/43"(!)/44" (already lower too!) -------------------------------------- Visit my HomePage at http://members.shaw.ca/finkirv/index.html Visit my Baby Sofia website at http://members.shaw.ca/finkirv4/index.htm Visit my OLDTIMERS website at http://members.shaw.ca/finkirv5/index.htm -------------------- Irv Finkleman, Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP Calgary, Alberta, Canada |
#19
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Hal:
:| - confused, stiff upper lip I'll recover by the time of your next post. grin John "Hal Rosser" wrote in message ... My brother quit the power company when they were switching to "underground utilities" - he got tired of burying those telephone poles so deep! And I had to give up chicken farming because the county extension agent said I was planting them too deep - I think I must have been planting them too near the underground power lines. "John Smith" wrote in message ... Reg: I can't even dream of burying a perfectly good, working, beautiful, sleek antenna! ... I shall refrain from burying any antenna, before its' time ... John |
#20
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the Great City of Birmingham (which yesterday suffered a tornado due to Earth warming climatic changes caused by American pollution of the atmosphere). Birmingham, in opposition to Manchester, will do anything to get into the news! ---- Reg. Hi Reg, I live in the Great City of Birmingham, and there was no tornado yesterday due to Earth warming climatic changes caused by American pollution of the atmosphere. We do have tornados here from time to time and have even before the American pollution of the atmosphere. Of course I live in B'ham Alabama USA so I am closer to the pollution than you are. The company I work for has spent billions on environmental projects as has a number of other companies. It is starting to make a big difference in the air quality over here. I doubt seriously the B'ham tornado was anything out of the ordinary (1 every 100 years). If you want to see who is really cranking out the pollution, look at third world countries who are attempting to progress, which takes energy that they can not afford, much less any pollution control. China comes to mind. Gary N4AST |
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