Pete, I think you're (and they) are right. I was thinking the difference in
phase velocity between coax and air made the compensation unequal on the
different bands, but I think I now see the (speed of) light. I stand
corrected.
--Dave
K0QE
----------
From: Pete Smith [SMTP:n4zr@contesting.com]
Sent: Thursday, December 16, 1999 9:08 AM
To: Dave D'Epagnier
Subject: RE: [TowerTalk] Re: The Ultimate One Tower System
At 08:49 AM 12/16/1999 -0700, you wrote:
>
>The velocity factor in the coax is the same on all bands (of
course), but
>the amount of phase shift between the two antennas will be
different on
>different bands if unequal line lengths are used. The horizontal
offset
>between the two antennas can only be compensated for on one band
with this
>technique.
Dave, I think Guy and Jay are right -- because a 5-foot offset, for
example, induces twice the phase shift on 10 that it does on 20.
Inserting
a 5 x VF length of coax would introduce the right amount of
compensation on
each band.
73, Pete N4ZR
Don't forget to update your entry in the contest station database
http://206.102.70.3/search.htm
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