[TowerTalk] The Care and feeding of an 80 meter Zepp

[Jim Brown]

On Sun, 27 Mar 2005 20:13:33 -0900, Justin Burket wrote:

>I settled on an end fed cut for 80 meters. 

Others may disagree, but I recommend you end feed the wire against 
some sort of counterpoise arrangement. Perhaps the counterpoise 
could be a wire dropped out the window on the opposite side of the 
house from the wire. Yes, your shack will be hot with RF, but that 
should be no problem if you do other things right. 

Forget this silly stuff with the 300 ohm line and the coax. Simply 
run a wire from one end of the antenna to the center conductor of 
a coax input of your tuner. Then connect the chassis of both the 
tuner and the rig to the counterpoise. 

What's a counterpoise?  It's nothing more than the other side of 
the antenna -- someplace for the RF current to flow to complete a 
path for the antenna. See photos of what I did in my QTH in a 
Chicago mixed residential/business neighborhood. See the link 
below.

http://audiosystemsgroup.com/K9YC/k9yc160TopLoad.htm

My counterpoise is the wrought iron fence running around the front 
of the house, plus some wire radials running every which way. This 
antenna works quite well on both 80 and 160, but quite poorly on 
higher bands. 

The noise you hear is probably a combination of all the electronic 
gadgets in your house, all the wall warts, Ethernet wiring, 
computers, printers, etc., as well as those of your neighbors. 
Welcome to the 21st century.  You want to get rid of it?  First, 
find a 12v battery big enough to run your radio as a receiver 
only, then kill power to your own apartment only, and see if any 
of the noise goes away. If it does, chase it down by the process 
of elimination. The rest you're stuck with. 

The only ways to reduce what's left is with special receiving 
antennas like shielded loops, and with a noise canceller. The 
problem with both of these is that they can only kill noise coming 
from one or two directions, and you still hear the rest of it. 

Jim Brown K9YC