Hi everyone:
One of my antennas is a dipole ~30 feet up that's a 1/2 wave at around 5.3
MHz (88' long). I feed it with 600 ohm open wire feed and use it on 75
meters where it's around 1/3 wave long. One midday a few weeks ago, I
transmitted a 10 - 15 watt carrier for several minutes in a dead part of the
80 cw band and walked around under the dipole with a cheap field strength
meter. While the whole undertaking was crude, it was pretty clear that the
field was strongest at the ends of the dipole and weakest near the feed
point. I was not expecting this, mainly because with a 1/2 wave dipole I
understand the current is max at the feedpoint. while this antenna is
shorter I did not think that would matter that much. I was wondering if
someone with modelling software could tell me (explain) the current
distribution on a 1/3 w. dipole and if possible tell me the modelled swr for
an 88' dipole at 30 feet, fed with 600 ohm open feed on 3.75 MHz and the
resistance/reactance. Since I've never used any of the antenna packages, I
don't know if I'm asking a great deal or not, so if it's a big hassle I
apologize--please disregard. I use this antenna on 17-80 m.
tnx & 73,
Rob
K5UJ
k5uj@hotmail.com
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