A 33 foot vertical is not a particularly good choice of length for
use on multiple bands. End fed it will have a very high impedance on 20
meters.If you can make it longer it will be an easier match on 20 meters
for whatever tuner you use. I used to use a 40 foot vertical with a
Kenwood TS-50 and AT-50. It worked well for all bands 80 through 15
meters. I used 40 foot length because the MS-44 mast sections are five
feet long. Fourty Three feet might be a nicer length, since that is
5/8ths wavelength on 20 meters. I fed the vertical directly with coax,
and had the AT-50 on the operating table. A remote tuner at the feed
point would have been better. There is no particular reason to make the
antenna self resonant on any band, especially when you are using a
remote tuner at the feed point. The notion that resonant antennas
radiate better is a ham myth. You may be able to keep the SWR on the
feed line low on a band or two by picking a resonant length, which can
reduce losses in the transmission line. The losses should be pretty low
anyway, and if you are using a remote tuner at the feed point you can
forget about that. There is a good reason to to avoid making an end fed
antenna a multiple of 1/2 wavelength long on a band you would like your
tuner to be able to match it on.
What I said about resonance not being important does not apply to
parasitic elements in an array.
DE N6KB
David Humelsine wrote:
I have decided to up grade my ham shack with a Jupiter. My present set up is an Argonaut V with a 33 foot vertical and 36 radials. I have a SGC 237 tuner at the base of the vertical for multi band use. If I order the Jupiter with the internal tuner and install a balen at the base of the antenna how well can I expect it to work. My personal feeling is an external tuner like the LDG 1000 pro would be better. Comments please off line from anyone using the Jupiter and 33 ft vertical antenna would be appreciated.
David N5 WMQ
n5wmqmail@comcast.net
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