Input basic measurements at transmitter to see what's really happening at 
the antenna.

        http://www.softcom.net/users/kd6dks/antenna.html

A point that this program demonstrates well is that a relatively small 
amount of loss in a feedline can make very poor SWR at the antenna look 
reasonable acceptable at the transmitter. For example an SWR of 1.5 at the 
transmitter with a 3 dB feeder loss gives an antenna SWR of 2.3 and loses 
73% of the power in the feedline. (50% would be lost with a perfect match.)

Go to a very lossy feedline and the results can be quite amazing.
eg Feedline = 6 dB. Loss in feedline with perfect match would be 75% (=6 
dB). But with SWR. But with SWR = 1.5 at transmitter the antenna SWR = 8.8 
and overall loss in feedline = 96.5%! (3.5 watts of antenna power for 100 
watts transmitter power).


        RM


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