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[Towertalk] KLM Tribanders

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Subject: [Towertalk] KLM Tribanders
From: btippett@alum.mit.edu (Bill Tippett)
Date: Wed, 31 Jul 2002 22:28:57 +0100
K4XS wrote:
>Someone told me a while back that in stacking the KLMs it was imperative to 
keep the + on the same side for the entire stack.  Is this so, and if it is 
what is the reason for doing so?  I know you can check the balun with the MFJ 
259 to determine which side is which and plan to do so but does it really 
make a difference?

        Yes, the marks look like 5 dots making a + sign.  As others
stated, you must keep them aligned to keep the antennas in phase.  I'm
not aware of a way to use an MFJ 259 to check for phasing, but the
following post suggests a good approach:

http://lists.contesting.com/pipermail/towertalk/2000-October/034295.html

KLM apparently was consistent at least from the early 80's until they
went out of business in the way they marked phasing, but I also have
a VERY old balun (but using the new PVC case construction) which has
no marks at all.  For your antenna in the air, you will probably need
to make a visual inspection.  There is another way but it involves
feeding both that one and the new one together, making measurements at
a distance with another antenna at a height half the distance between
the two under test and checking signal strength.  When "in-phase", the 
received signal should be very noticeably stronger than "out-of-phase".

                                                73,  Bill  W4ZV




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