[CQ-Contest] NAQP Lessons learned

[Bill Coleman]

On Jan 23, 2006, at 2:22 PM, John Geiger wrote:

> Low antennas are less than ideal, but will still work.  I have a 40  
> meter
> DXCC hanging on the way which was earned running 100 watts to  
> pretty poor
> antennas-mainly a long wire at about 25 feet high or a dipole with  
> a max
> height of 30 feet at the apex.  Most small lots will still handle a
> vertical, even if you can't get alot of radials down.  A vertical with
> nothing but a ground rod is better than QRT.

A dipole at a modest height will work well on 40m, but I had a lot of  
trouble with 80m using a dipole at 30-40 feet.

I did some modeling with MMANA, and it's pretty obvious why - at that  
height, just about all of the pattern is straight up. That may be  
useful for NVIS contacts out to a couple of hundred miles. Depending  
on where you live, that may be good for a domestic contest, but it is  
no good for DX. For me in Georgia, most of the domestic ham  
population is going to come in at angles below 50 degrees, and  
certainly all of the DX.

I've had much more success the last couple of years by shunt feeding  
my 15m tower for 80m and 160m. (The matching network has proved to be  
an interesting challenge, as right now I am QRT on those bands  
pending a repair) The models of even short verticals with a handful  
of radials show nearly all of the pattern is below 45 degrees.

Seems like anyone in a small lot with trees or a modest tower can  
have an effective vertical on the low bands. Plan for 20-30 radials,  
as long as you can make them, up to about 1/4 wave.

Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net
Quote: "Not within a thousand years will man ever fly!"
             -- Wilbur Wright, 1901