Charles,
Here are some direct answers to your questions:
On Tue, 21 Oct 1997, Charles H. Harpole wrote:
> 1. just how long should it be (not in wavelengths, not in meters, but in
> gud ole American FEET) for 160 meters????
Based on computer models, and on-the-air experience, good choices are 580,
880 and 1160 feet. If these are inconvenient for you, use what you can.
Lengths less than 500 feet perform significantly poorer than longer
lengths.
> 2. what should be on the far end? a carbon resistor? or what? and of
> what wattage value? and of what resistance value?
Use a 470 ohm carbon composition resistor. If you have an antenna
analyzer, you could optimize the resistor value for flat VSWR across the
range 1.8-10 MHz. If you don't have an antenna analyzer, don't worry
about it, just use 470 ohms! VSWR flatness indicates minimal reflections
from the far end. Wattage value is not critical, I've used everything
from 1/2 watt to 2 watts and none have ever failed at my QTH.
You will need a 9:1 transformer to feed the Beverage, and suitable ground
rods at each end.
Lay the feedline on the ground or bury it. If you must raise the feedline
above ground it will also behave like a Beverage and you will need to take
special precautions to isolate the antenna currents on the feedline shield
from the Beverage feedpoint ground.
73!
Frank
W3LPL
donovanf@sgate.com
--
FAQ on WWW: http://www.contesting.com/topband.html
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|