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centos45 Antenna-Theory.com Newbie
Joined: 22 Jul 2015 Posts: 2
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Posted: Wed Jul 22, 2015 8:54 pm Post subject: 45 meter long wire antenna 30/15 |
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| Hi, I came across a a long wire antenna at a flea market the other day, the guy selling it wasn't sure which band(s) it was for, anyway I bought it for a small amount of money and got it home and measured it. its 15 meters on one side and 30 meters on the other side with an OS259 connector between. the question is- is this a multi band antenna? or is it fixed at a specific frequency? if multi-band how will it perform on the various bands? and what is the reason for different lengths on each side? I just want it for listening general coverage 1 to 30mhz and also the 6m band at 50mhz but im interested in knowing which band(s) was this antenna specifically designed for? also what is the best way to mount the antenna considering my garden is only 30 meters by 20 meters. could it go from the ground up and back down? and if I make it in to a V shape with some slight turns how will it effect the performance? thanks |
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admin Site Admin
Joined: 03 Jan 2007 Posts: 247
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Posted: Sat Jul 25, 2015 6:56 pm Post subject: |
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45 meters is a half wavelength for 3.3 MHz. So the antenna probably works well at multiples of 3.3 (6.6, 9.9, etc). The antenna efficiency will probably have several dead spots (1MHz probably won't work well, nor 4.5MHz).....
If the antenna is fed in the center (equal arm sizes), then the antenna only works at odd multiples of 3.3......
If you bend the antenna, keep the bend angle at less than 90 degrees. Keep the antenna as high as possible |
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centos45 Antenna-Theory.com Newbie
Joined: 22 Jul 2015 Posts: 2
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Posted: Sat Jul 25, 2015 8:01 pm Post subject: |
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thanks for the info  |
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