[TowerTalk] RF in the shack

[Jim Thomson]

Date: Thu, 9 Mar 2017 05:00:37 +0000 (UTC)
From: <ko7ss at yahoo.com>
To: "towertalk at contesting.com" <towertalk at contesting.com>
Subject: [TowerTalk] RF in the shack

My antennas are all above a metal cabin roof. I had big problems, spent $$$, and now it all works great, even with 1500 W RTTY on 80M:
http://www.yccc.org/Articles/W1HIS/CommonModeChokesW1HIS2006Apr06.pdf

http://www.balundesigns.com/

This should not be a problem!
73 Bill KO7SS on Mt Lemmon, AZ


##  The above  W1HIS article needs a serious re-write. 

##  W1HIS did an article for   jan + feb 2013 NCJ, using 3 turns of 142 around a pair of type 31 beads in binoc fashion.
Works, sorta, but peaks at 15 mhz,  with 2200 ohms of rs,  then drops off  rapidly on either side.   So 2 are used in series.   This 
is the problem with the binoc config, whether beads or torroids used.   Its a real trick to peak the response where u want it. 

http://www.kf7p.com/KF7P/Tech_Resources_files/NCJ%20Jan-Feb%202013%20p1of3.jpg

http://www.kf7p.com/KF7P/Tech_Resources_files/Ecellent%20Choke%20%20p2of3.jpg

http://www.kf7p.com/KF7P/Tech_Resources_files/Excellent%20Choke%20p3of3.jpg

##  U could stagger tune  2-3 of these, so they cover the entire spectrum a bit better, but binoc config is a tough cookie
to work with.   too much stray C. 

Jim   VE7RF