[TowerTalk] Cushcraft X-940 Question

Chris & Bill Shell n6ws@msn.com
Sun, 27 Sep 1998 20:16:43 -0700

Thanks in advance for any responses to this query.

I just finished putting the 40m element, X940, on my Cushcraft X-9.  The
instructions, step 7, have you move the boom-to-mast adapter 30.5 inches to
the rear between the 2nd 10m and 15m driven elements.

My question is, why?  The manual just states, "This is necessary to balance
the antenna on the tower mast."

The center of gravity shifts 14 inches to the rear when the element is
added, to a point between the two 10m driven elements.  It seems to me that
moving the balun to the front of the first 10m driven element and placing
boom-to-mast adapter between the 10m driven elements would be closer to the
actual center of gravity (CG).

Leaving the mounting point in the original place, 14 inches in front of the
CG is just about the same as moving it 16.5 inches behind the CG.  Is there
another reason that the adapter should be moved that is not readily

TU es 73, Bill

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