[CQ-Contest] Stubs - 40 & 15 meters

Zivney, Terry 00tlzivney at bsu.edu
Fri Jul 20 04:45:07 PDT 2012

 On 7/5/2012 11:11 AM, Joe wrote:
> The Stubs on this page
> http://www.k1ttt.net/technote/k2trstub.htm
More on these stubs. Say one station is on 15 and another is on 40. 
There is no way for the 15 station to block the 40 station signals is 
there. All one can do is to insert a 15 stub on the 40 station to try to 
block any signals true?
Or is there a way to block with a stub the 40 meter signals without of 
course also killing 15 because of the odd multiple thing?
Joe  wb9sbd
> Joe WB9SBD


Pretty simple - see W2VJN's book on stubs "Managing Interstation Interference"

My copy is not at hand here, but as I recall it involves a quarter wavelength of 
coax at 40m, but 'tapped' up 1/4 wavelength from the shorted end on 15m.
That is, use a Tee connector; on one side of the tee is a 1/4  wavelength shorted
stub on 15 and on the other side of the tee is an open ended 1/2 wave stub on 15.
But, check the book for more details.  I tried it back when I did a book review of
it for NCJ and it worked FB.

Terry N4TZ/9


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