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Aluminum spreader quad
I was talking with some guys this AM about building a quad antenna
using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie |
Aluminum spreader quad
"JIMMIE" wrote in message ... I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie A few years ago, I had a Hygain 3-band quad with aluminum spreaders. "Strategically placed" insulating rods divided the spreaders into non-resonant, neutral segments. Philo |
Aluminum spreader quad
On Aug 15, 4:30*pm, "Philo" wrote:
"JIMMIE" wrote in message ... I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie A few years ago, I had a Hygain 3-band quad with aluminum spreaders. "Strategically placed" insulating rods divided the spreaders into non-resonant, neutral segments. Philo I was thinking about a single band quad. I figured that on a single band quad the length of the spreader would be either 1.414 or .707 (depending on how you see this) times the lenght of one side of the quad. I dont think this would be close to being resonant. Jimmie |
Aluminum spreader quad
JIMMIE wrote:
I was thinking about a single band quad. I figured that on a single band quad the length of the spreader would be either 1.414 or .707 (depending on how you see this) times the lenght of one side of the quad. I dont think this would be close to being resonant. Are the two 0.35WL spreaders shorted together in the center or are there four 0.175WL spreaders insulated in the center? Seems to me, this could easily be modeled using EZNEC. I've never done it but I'll bet others have. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
Aluminum spreader quad
On Aug 16, 9:54*am, Cecil Moore wrote:
JIMMIE wrote: I was thinking about a single band quad. I figured that on a single band quad the length of the spreader would be either 1.414 or .707 (depending on how you *see this) times the lenght of one side of the quad. I dont think this would be close to being resonant. Are the two 0.35WL spreaders shorted together in the center or are there four 0.175WL spreaders insulated in the center? Seems to me, this could easily be modeled using EZNEC. I've never done it but I'll bet others have. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com Haven't tried to build it yet, just kicking around the idea since I have the aluminum and not the fiberglass. Jimmie |
Aluminum spreader quad
Hi Jimmie
Some years ago I made a 3 el 10M quad that was actually a bow tie arrangement. ie the spreaders were "driven" and the side "elements" were rope. Probably not what you are thinking about but it did look like a 3 el 20m quad! I should have modeled it in later years but never got around to it. It worked okay at the time but I wasnt exactly doing any extensive testing. Does modeling the metal spreaders give you any ideas? Cheers Bob JIMMIE wrote: I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie |
Aluminum spreader quad
On Aug 16, 7:13*pm, Bob Bob wrote:
Hi Jimmie Some years ago I made a 3 el 10M quad that was actually a bow tie arrangement. ie the spreaders were "driven" and the side "elements" were rope. Probably not what you are thinking about but it did look like a 3 el 20m quad! I should have modeled it in later years but never got around to it. It worked okay at the time but I wasnt exactly doing any extensive testing. Does modeling the metal spreaders give you any ideas? Cheers Bob JIMMIE wrote: I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie Ive never really gotten in to modeling antennas that much. Ill probably just build something and see what happens. Jimmie |
Aluminum spreader quad
On Aug 17, 12:48*am, JIMMIE wrote:
On Aug 16, 7:13*pm, Bob Bob wrote: Hi Jimmie Some years ago I made a 3 el 10M quad that was actually a bow tie arrangement. ie the spreaders were "driven" and the side "elements" were rope. Probably not what you are thinking about but it did look like a 3 el 20m quad! I should have modeled it in later years but never got around to it. It worked okay at the time but I wasnt exactly doing any extensive testing. Does modeling the metal spreaders give you any ideas? Cheers Bob JIMMIE wrote: I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie Ive never really gotten in to modeling antennas that much. Ill probably just build something and see what happens. Jimmie I slid Al tubing over the supports for my two meter quad except for the last two inches toward the tip and I cant tell any difference in operation VSWR is the same. AGC voltage on my receiver is the same as usual for a local repeater. Whether or not the boom ends of the tubing were connected together also had no discernible effect. Jimmie |
Aluminum spreader quad
There is an article in QST april 1992 about building a 5 band 2 element quad
with aluminum tubing KC6T is the one who built it. It also is in 2007 ARRL Handbook. Shows & describes how the spreders are built with dinensions.... "JIMMIE" wrote in message ... I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie |
Aluminum spreader quad
On Aug 19, 2:11*am, "Howard K0ACF" wrote:
There is an article in QST april 1992 about building a 5 band 2 element quad with aluminum tubing KC6T is the one who built it. It also is in 2007 ARRL Handbook. Shows & describes how the spreders are built with dinensions....."JIMMIE" wrote in message ... I was talking with some guys this AM about building a quad antenna using aluminum spreaders. I know that it at least the tips of the spreaders would have to be made of insulating material such a fiberglass but the consensus seemed to be that most of the spreaders should be non-metalic. I was wondering if anyone here had built a quad with almost all of the spreaders made of metal and what was the results. Jimmie- Hide quoted text - - Show quoted text - Thanks, I ll see if I can pull that up in the QST archives. I may even have that handbook. Jimmie |
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