[TowerTalk] Cushcraft 40-2CD and M2 15M6 on the same mast - crossedor not

[Dave Hachadorian]

----- Original Message ----- 
From: "Jorge Diez - CX6VM" <cx6vm.jorge at adinet.com.uy>
To: <TOWERTALK at contesting.com>
Sent: Thursday, December 31, 2009 3:44 PM
Subject: [TowerTalk] Cushcraft 40-2CD and M2 15M6 on the same
mast - crossedor not

> I removed now the TH7 and replace it with a M2 six element
> monobander
> (15M6). Still must go crossed (90 degrees offset) or may I put
> them pointing
> both in same direction (booms in parallel)?
-------------------------------


I would try the booms in parallel, and then do front-to-back
measurements on the two antennas. If the front-to-back ratio is
near spec, you can be pretty sure that the gain is ok too. F/B
ratio is the most sensitive test for interaction, and is easy to
measure. Instructions here:
http://lists.contesting.com/archives//html/Towertalk/1998-11/msg00502.html

If f/b is degraded, try the booms at 90 degrees.

Sometimes the 40M feedline dangling off the 40-2cd will make the
DE near-resonant on another band. Lengthening, shortening, or
shorting the 40M feedline can cure this problem.

Because of its loading coils, the 40-2cd is not resonant on 15M.

Happy New Year to all!

Dave Hachadorian, K6LL
Yuma, AZ





























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