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[Towertalk] It ain't the fence any more.

To: <towertalk@contesting.com>
Subject: [Towertalk] It ain't the fence any more.
From: k2av@contesting.com (Guy Olinger, K2AV)
Date: Sun, 18 Aug 2002 01:40:08 -0400
How about one burned contact in the Comtek box? Or a contact not quite
closing.

You've solved the fence problems. The individual SWR tests proved
that. What's left is unrelated.

Would appear that the only thing that is left is the wiring and stuff
in the Comtek box.

Here's how you prove it.

Unconnect the coaxes from the Comtek hybrid unit to the verticals.
Take the NW coax and hook it to the NE port on the Comtek. Connect the
NE coax to the SE port, etc.

Now rerun the power dump tests. See whether or not the problem has
miraculously rotated 90 degrees clockwise, that the 2% and 20% dump
switch settings on the Comtek control box have changed.

If the problem rotated, then it's in the antennas and we still have
something interesting to discover, no matter how improbable.

If the problem did not rotate it's in the Comtek box, and you need to
have it looked at.

73, Guy.

==================================
I have a very nice looking three rail wood fence that now runs along
my 4SQR.
 Removing the goat wire for over 350 feet, then putting up then fence,
then
adding wood braces that acted as insulators breaking up the goat wire
for
another 100 feet on either side of the wood fence, has had an awesome
affect
on the individual SWR's of the antennas.  They are all now perfectly
match
with 5KHz of one another- right around 3.540MHz-  The SWR of the
antennas
with the fence was up ranged from 3.540-3.640MHz-

But the bad news is that I am still seeing the problems with the
varying
power port figures.

They remained unchanged ranging from 2% up to 20% at the same
frequency but
switching antennas.  They direction of how the array was pointing also
showed
varying resonant points at different frequencies as it relates to
minimum
power dumped into the Hybrid power dump port.

So the main problem remains-But I've discovered something else.

The power meter on the 756 Pro shows 100 watts output unless the VK
antenna
is on.  On the VK antenna, I can only get 50 watts out.  I switched
feedlines
and the problem remains. How can it do this with a dummy load attached
via a
hybrid coupler device?? So now I'm getting close to figuring it out by
narrowing down things with the fence-  The problem with the array has
to be
between the rig's output and Comtek control box at the antenna-  All
else has
been ruled out-

Can anyone tell me why the max power out to the VK antenna is 1/2 of
the
power out the other antennas?  What possiblities can cause this in a
hybred
coupler?

What could the problem(s) be?? Or am I barking up the wrong tree
thinking its
the coupler?   The F/B on this antenna is awesome between what I am
hearing
and the reports I get--  If not for monitoring the power port watt
meter, I
would never of suspected a problem-

That's all for now- I have several emails with good suggestions and
requests
that I update people on my progress-  So there you have it-  Open to
any
ideas on solving the power output problem-


73  Paul  N0AH





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