[SECC] NAQP...40 Meters

K4SB k4sb at earthlink.net
Mon Jan 12 18:04:55 EST 2004


"Macie, Gordon" wrote:
> After sweepstakes and naqp I am convinced my weak area is 40 meters. I will
> be putting up another 40 dipole soon. My current one is at 30 '..
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I have mentioned this before, but at a height of 30 feet, radiation
will be almost 90 degrees in all directions. In effect, "40
lengthening out" simply will not occur.

There are 2 solutions for this problem.

1. Use the height of 30 feet for a vertical T antenna, and increase
the top of the "T" to a point where radiation resistance is high. Or,
plant a 33' vertical and radials.
I don't really like the idea of this, but you can also pick out the
tallest tree within
reasonable distance, and rig a horizontal mast as high as you can get
it. Just tie the mast into position.


I believe Macie does not have a tower, but for those that do, the best
solution is to extend the mast above any antenna mounted on the tower.
If you can get an extra 10 feet, it then becomes a simple geometry
problem to determine how high the end supports of the dipole, or
whatever you put up there, to clear the beam as it rotates. All you
need is a thrust bearing mounted at the TOP of the new mast, and
locked to the mast in such a manner that the "outer" portion ( which
usually mounts to the top section base plate )
spins. Then, as you turn the beam, the antenna rotates beneath the
wires.
 
Now, I have to go climb a 70' pine and put up the last of 4 rope and
pulley arrangements.
Then, a wire Moxon on 40 will go up.

73
Ed

PS Still can't get the OMNI to transmit.


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