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[TowerTalk] Force12

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Subject: [TowerTalk] Force12
From: (Pete Smith)
Date: Wed, 03 Oct 2001 08:00:59 -0400
At 05:58 AM 10/3/01 -0400, Gary J. Ferdinand  W2CS wrote:
>I'm surprised Force 12 doesn't recommend you just replace their antenna with
>a dummy load. BW will be improved still further and cost will be kept to a
>minimum, although gain and F/B might suffer a tad :)
>Sounds like their BW  quote depends on there being enough loss in the
>feedline to achieve it.  Rather strange to say the least!

I think F12 is being treated a little unfairly on this issue.  Their specs
in general are the most honest, specific and verifiable of any antenna

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).

73, Pete N4ZR

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