First ! Thank you all for your comments ... Now to explain the basis of my
antenna . My first antenna for 160 when I moved to the high Desert was the
first tower you saw on my web site . It is 90 feet with 2 yagi on it I shunt
fed with a single wire and only had about 25 kc band width.
Tom if you go back and read my note you will see I never said any thing about
ground loss, I'm not sure where you got that . Herb did say ! we sometimes over
look it . I agree that, when we have large band width, a poor ground system,
the swr seems to be good.. whoa , ! something not right.
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With that out of the way ::: I will try to give everyone a better understanding
of my cage antenna . I have installed the cage antenna for other hams using 2,
3, 4 and 6 vertical wires ::. ( I use the 6. ) They all work well . Once you
pass 6 it does'ent seem to make much difference . With the 6 vertical wires
the impedance come to near 50 ohms , As you know the impendence will change as
you move up and down the band,
(Your rig will tune ok ). My cage is 49 ohm at 1.830. close enough for
Government work . It is fed direct with 50 ohm coax . The cage antenna is a
very forgiven antenna. I found it to be a better performer than my single wire
fed tower .
The 70 foot vertical wires come from the top of the tower to an insulator and
tied off. near ground level . They are held out away from the tower by 3/4 pvc
tubing . I solder all 6 of them to a number 6 copper well wire around the
circumference, ( an 8 foot circle at base of the tower ).. I do the same for
the radial system below the insulator . I use the number 6 copper well wire
and tie all the 1/4 wave radial to it .
The insulators are all tied to a 10 foot 1/2 copper tubing pressure washed into
the ground .
(Easy out here in this sand bed ). The number 6 wire for the radial system is
soldered to the copper tubing .
Then I take a number 4 welder cable from the tower base to an 8 foot ground
rod,. I attach a wire to it and solder it to the wire that ties all the
copper tubing together with the 62 radial .
The cage antenna is a grounded antenna. it is not a new antenna. it's been
around for many years you can find lots of information on it . One that comes
to mind is the arrl antenna compendium volume 2 page 36 .
I have seen many different designs of this antenna and they all work well.
This was my way of making one . mainly because of band width and the high winds
we get here. ( It stays together .) snip snip
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I had 2 of these antennas up. Took one down . Now working on the base for a
larger tower. I also have the receive antennas down . If all goes as plan I
will be back next season with a better receive and TR system
73 Randy W6OAR
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