Rod's idea is by far the best. Slopers are weird creatures. While you can
broadband antennas by making the elements with a large diameter (as in a cage)
the mechanical complexity isn't worth it. If they absolutely positively must be
resonant, well...
Kim N5OP
From: Rod Greene via TowerTalk <towertalk@contesting.com>
To: Roger (K8RI) on TT <K8RI-on-TowerTalk@tm.net>; "towertalk@contesting.com"
<towertalk@contesting.com>
Sent: Thursday, August 17, 2017 2:25 PM
Subject: Re: [TowerTalk] Broadbanding 80 meter dipole
Or use an auto tuner at the feedpoint to match the slopers on whatever
band/freq you want to use. That's what I do.
73, Rod/w7zrc
From: Roger (K8RI) on TT <K8RI-on-TowerTalk@tm.net>
To: "towertalk@contesting.com" <towertalk@contesting.com>
Sent: Thursday, August 17, 2017 12:33 PM
Subject: [TowerTalk] Broadbanding 80 meter dipole
I've seen a few possibilities in the past, but I'd like to add a dew
slopers to come up with the 5 used for some directivity, gain and front
to back. Switched coils at the feedpoint with frequency sensing would
likely work. I've had excellent results with just a couple switched
slopers on 40.
To complicate things I'd like to do this and maintain the dual band 75 /
40 meter operation, which would likely require separate feedlines. The
unused line would / could end up as a stub. I could possibly use the
frequency sensing to disconnect the coax for the unused band.
Thoughts?
--
73
Roger (K8RI)
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