Thread: Multi-band dipole question
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Old April 19th 07, 08:35 PM posted to rec.radio.amateur.antenna
Buck[_2_] Buck[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 118
Default Multi-band dipole question
On 19 Apr 2007 12:17:00 -0700, wrote:

Hello,

Just joined the group and I have a question about constructing a multi-
band dipole.

I plan to construct a 80/40/20/15 band multi-element dipole using
separate dipole wires for each band,
but a single feedpoint. My question is: how important is the spacing
BETWEEN the
individual band wires. I understand that they can't/shouldn't touch,
but is there any distance
that is optimal? or is just keeping them from touching enough?

Thanks,

Mike
KD7VRG

I have used those antennas most of my life. I call mine a
parallel-fan dipole. I usually use 4" spacing for convenience. I use
PVC pipes with holes drilled in them the same diameter of the wire for
spacers.
However, there is a little secret to the parallel-fan. If the spacing
is pretty close to 8 inches apart, then you can setup the 75/80 meter
element and reverse engineer the length to the frequency. THen
substitute the new formula for the 468/f formula and you won't do so
much trimming on the other elements.

The advantage to the 4" spacing is that on 80 & 40 meters, you get a
broader bandwidth.

I really don't know of any better dipole arrangement when there is
room enough for this one.

Buck
N4PGW

--
73 for now
Buck, N4PGW
www.lumpuckeroo.com
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