[TowerTalk] JK Mid Tri 15M Issue

[Jim Brown]

Jack's suggestion is a good one. If there IS interaction, what happens 
when disconnecting that feedline will strongly depend on the length of 
the feedline between the antenna and where you disconnect it.

Our contesting trailer for county expeditions and FD has the feedpoint 
for 80, 40, and 20 antennas within about 3 ft of each other. We run 500W 
from a KPA500 on each station, so we have double stubs on both the 40 
and 80M feedlines, optimally placed on each feedline with respect to the 
antennas. That placement is discussed in great detail on my website, in 
a piece published by National Contest Journal, and with a pdf of slides 
for a talk I've done at Visalia, Pacificon, and to several clubs.

k9yc.com/publish.htm

When two antennas closely spaced antennas are related by their second 
harmonic, the lower frequency antenna can screw up the pattern of the 
higher frequency antenna. It so happens that the optimally placed stub 
nearest the antenna is also optimally placed to kill that pattern 
distortion!

73, Jim K9YC

On 9/4/2024 1:16 PM, john simmons wrote:
> How about opening/shorting the 40M feedline whilst testing 15?