[TowerTalk] bad coax? and EF-240 tuning

leewells@lexmark.com leewells@lexmark.com
Wed, 15 Oct 1997 14:02:14 -0400

I'm having a little trouble getting the elements for my Force-12 EF-240
tuned up properly.  I hauled the driver element up the tower yesterday
to check out the resonant frequency, and found two suprises...the
resonant freq was much higher than expected (7.300) , and the SWR was 2:1 at the

So I lowered the element back to ground level, checked it again and the
resonant freq had shifted up by about 50 Khz (sounds okay).  But then
I changed feedlines (RG-8X), and the freq was down to 7.115 (closer to expected)
but the SWR is still around 2:1.

The original coax is 9913F (about 150-160 feet), its brand new, never
been on the air or outside.  The second coax is some old RG-8X that is 
about 40-50 feet long.

A couple questions:

1)  Should the 40 Meter element have a dip of 1:1?????  If so I've got some
work to do on that element.

2)  How do I figure out if my coax is bad???  Would a bad connector installation
cause what I'm seeing (maybe the dielectric got too warm and the center conductor
migrated too close to the shield?)

Thanks & 73's
--Lee - KT4ZX
Georgetown, KY

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