----- Original Message -----
From: Tom Rauch<mailto:w8ji@contesting.com>
To: k8do@mailblocks.com<mailto:k8do@mailblocks.com> ;
topband@contesting.com<mailto:topband@contesting.com>
Sent: Friday, December 31, 2004 7:12 AM
Subject: Re: Topband: Re: Increasing bandwidth 160m L
> Can't be done... If you intend to cover the band get busy
building
> either a remote tuner or switched/tapped networks for
matching..
A thicker element will increase bandwidth.
An element that is self-resonant will increase bandwidth
over one that is intentionally too long or short.
A very low reactance parallel L/C circuit across the
feedpoint will increase bandwidth. (The reactance of each
component has to be a low value, that's why stubs like
coaxial cable stubs used in coaxial dipoles and such won't
do much of anything unless they are very low Z or you
parallel multiple low-loss low-Z stubs.)
I'm reasonably sure a combination of these three techniques
would easily cover all of 160 meters without retuning.
73 tom
Another approach would be to use a series/paralllel reactance to tune out the
reactance and then use a toroid transformer to transform the impedance. This
should be broader.
John K9DX
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