On 12/10/97 4:57 PM, Lee Buller at k0wa@southwind.net wrote:
>One of the things that tick me off about a simple dipole is that the
>bandwidth, say on 40 meters, is very poor. If I cut the thing for 7050 and
>the dipole matches very well at that frequency, by the time I am at 7250 the
>match stinks.
>
>Here is what I have experimented with with a modicum of success.
>
>1. Two dipoles on the same feed line .... upper and lower part of the band.
>
>2. Used RG59 as "wire" for the dipole to increase the thickness of the wire,
>this increasing the bandwidth.
>
>3. Used a tuner (I hate this for various reasons)
>
>Ok, so what have you guys found out that you are not telling me? And, why
>haven't you told me yet?
Use RG-174/U as the feedline. It should improve your bandwidth. (<grin>)
I'd be interested to hear your reasons why you hate using a tuner.
I don't see any clear solution offhand other than those you've suggested
-- multiple elements or thicker elements. You might try creating a
skeletal elements, as in a "bow tie" arrangement (a la Butternut
HF4B/HF5B), or really THICK conductor (as in 2-12 inches). Seems to me
that at 40m, going from .05" wire to .25" wire elements isn't a
tremendous change. (roughly 1/2500 wavelength, and 1/500 wavelength,
respectively)
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@radio.org
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search
|