I went out today and removed the coax from an 80M dipole. I added, in its
place, about 60 feet of vertical wire, ran six elevated radials, put in a
small ground rod, and hooked it all up. So I now have a "T antenna" for
160M to use as a vertical for the ARRL 160M contest.
My problem is that I have about a 3 to one SWR at resonance. I suspect this
is so because my feed point Z is probably around 15-20 ohms. I put a 3KW
MFJ tuner on it and it wants to arc at about 1100W output. (I know, I know
- but it is the only tuner I have for 160M)
I tried the antenna and it seems to hear everything about 2 S-units louder
than the inverted vee does at 80 feet. So it is going to work good, I think.
So I need a better way to match the antenna and probably should do it at
the feed point. Does anyone have a suggestion as to the easiest way to do
this? Would a coil or capacitor to ground do the trick like I used to do
with mobile antennas? I looked in the ARRL Antenna book and ON3UN's book,
but nothing jumped out at me for matching current-fed T antennas.
I will only have Friday to work on the problem because I have a committment
for Thursday. So I am hoping that the matching task will be simple and
quick. Any suggestions?
Some of you are still waiting for my comments about the 6 element inverted
vee wire beam. I am thinking about what I want to say and will provide
feedback soon.
73, Richard
K5NA@BGA.COM
http://www.realtime.net/~k5na
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