[Antennas] Multiple dipole spacing

2002年8月12日 13:27:04 -0400

Hi Rolly,
Try looking at the antennas on the Alpha-Delta web site:
http://www.alphadeltacom.com/
A-D does include some drawings and pictures in the on-line installation
info. It may give you a visual clue about spacing.
The few multi-band dipoles I've seen all seem to space the antenna wires
about 12" or more apart. A few had 36" standoff tubes for three wires,
giving as much as 18" of space. The last standoff was tied back to the top
wire with dacron, kevlar, or other non-conducting rope. If it was my
project, I would be tempted to use another piece of 1/2" pvc. The idea is
to not have this piece of rope/support soak up water and become a conductor
when it rains.
There have been a few similar homebrew projects written up in QST over the
years. The ARRL antenna book may have a few also..
Good luck.
73
Frank
 ._._.
----- Original Message -----
From: "R Goodspeed (W7DGX)" <[email protected]>
To: "Antenna Reflector" <[email protected]>
Sent: Monday, August 12, 2002 9:10 AM
Subject: [Antennas] Multiple dipole spacing
> Gentlemen,
>> I want to build a multiple dipole arrangement with one single feed
> point, and the higher frequency dipoles hanging below the lowest
> frequency dipole. The desired bands are 20 meters, 17 meters, 12 meters,
> and 10 meters.
>> What separation spacing is required to assure no flashover or melting
> will occur using legal limit power. Is PVC pipe good enough to be the
> spreaders to maintain the dipole separation spacing. Ten foot lengths of
> schedule 40 pipe is 1ドル.44. Are one or two feet separations sufficient??
>> >From my reading, the spacing must be greatest at the ends of the
> dipoles, because it is the highest voltage point. Is that true with the
> other dipoles being connected at the same time???
>> How much interaction should I expect? How would that affect the 'normal'
> length of a dipole?
>> Present plans involve hanging the dipole ends from trees with a rope and
> pulley arrangement that will allow lower the antennae for adjustments
> (and repairs if needed).
>> Thanks for reading this.
>> Thanks for any information you folks may provide.
>> Rolly W7DGX
>>> - - -
>> Your moderator for this list is:
> Larry Wilson KE1HZ [email protected]
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