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Old April 20th 07, 01:55 AM posted to rec.radio.amateur.antenna
merlin-7 merlin-7 is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 41
Default Multi-band dipole question

I use a fan type dipole. The wires are 66' 33' and 16' each side so double
that for total length. (befor I tuned them but thats close) with an air
wound choke at the feed point.
Fan is not exactly right for my antenna ...here is what I did...

I used pvc as a spacer between each wire, the first spacer is 12 inches
from the feed point (I wanted to get the wires apart from each other as
close to the feed point as possible to minimise interaction between them)

They are separated 12 inches apart over the whole length and hang under
each other, the longest being on top.
The top wire (the 66') is the one that has rope connected to it (via
insulator) to tie the ends of the dipole to whatever. in my case, It is an
inverted V so I used 2 20' poles to anchor the ends of the dipole to.

Since the ends of the 33 and the 16 footer were just hanging from the pvc
spacers attached to the 66 footer, I placed a weight at the ends of them to
keep it all from twisting up in high winds.

I also ran a line from the ends of the 33 footer down to my poles (a few
feet below where the ends of the 66 is tied off, for the same reason. ( I
find that weed eater string holds up really well for this and it is cheap)

I can use it on all bands from 10 to 80 meters and even right around 1.8
mhz on 160 with a cheap mfj tuner. (not sure why it will work at 1.8 mhz, I
never worked out the math)

I get great signal reports with it on my ts-440s (bare bone at 100 watts)
and as a general rule, if I can hear them, I can work them.
"Roy Lewallen" wrote in message
...
wrote:
So would a 80/40/20 be the thing to make? For whats it's worth, I
don't have a tuner right now.
I just want to cut each for the middle of the band for General phone,
and accept whatever bandwidth
I get.


That'll get you on those three bands and, as I mentioned, you can
probably get a reasonable impedance on 15 as well by fiddling the 40
meter antenna a bit. It won't be quite resonant on 40, but probably
close enough so your rig won't shut down.

Roy Lewallen, W7EL