On Wed, Oct 03, 2001 at 08:00:59AM -0400, Pete Smith wrote:
>
> My hunch is that when F12 first developed the C-3, the 15M SWR bandwidth
> was a little tight to enable them to stay under 2:1 across this wide band,
> so they specced the antenna on 15 using 100 feet of coax to achieve that
> magic number, which they thought was important for marketing purposes.
>
> And what does this magic number mean? Almost nothing. Without a tuner,
> some radios begin to fold back at SWRs well under 2:1. Some amplifiers
> don't like a load much over 1.5:1. Some radios, like my TS-930, soldier
> happily along into a 2.5:1 load. Some amplifiers will drive loads up to
> 3:1, depending on the band (like my SB-220). The practical advice is
> "don't worry about it." Use enough feedline to get from the antenna on the
> tower to your rig, no more and no less (hi).
>
Stated somewhat differently, use as much tower as the length of the
feedline will allow.
--
Bob Nielsen, N7XY nielsen@oz.net
Bainbridge Island, WA http://www.oz.net/~nielsen
IOTA NA-065, USI WA-028S
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
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