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Subject: Odd behavior of my C-3SS
Author: Eric Rosenberg/Jennifer Gruber <wd3q@erols.com>
Date: 09-Mar-2000 11:56:11
This retreads some old territory, but as I haven't been able to
get to the antenna (yet)< I thoughtI'd throw out some more
information.

- The antenna has been up 1-1/2 years.
- The antenna is mounted ~10 feet above the roof of my 75 year
old house on a Alinco roof tower.
- The feedline is 75 feet of Belden 9913, with a short (6 ft)
jumper of 9913 from the F12 balun to the main feedline.
- A 2m short vertical is mounted to the mast just above the yagi

The antenna has worked well for quite some time. In recent
weeks, its characteristics seem to have changed. The F/S and to
a lesser degree the F/B performance continues to be quite good.

The gain characteristics seem to have degraded. Often times, the
dipole that sits above the yagi by 20 feet outperforms or is at
least as good as the yagi. It's not consistent, but certainly
noticeable. Note that the SWR has changed, too.

The SWR curves seem to have changed.

14.025 = 2.0:1 (was 1.3:1)
14.125 = 1.4:1 (was 1.1:1)
14.225 = 1.1:1 (was 1.25:1)
14.325 = 1.2:1 (was 1.6:1)

21.025 = 1.2:1 (was 1.4:1)
21.125 = 1.2:1 (was 1.2:1)
21.225 = 1.2:1 (was 1.5:1)
21.325 = 1.2:1 (was 1.1:1)

28.025 = 2.8:1 (was 2.8:1)
28.125 = 2.1:1 (was 2.5:1)
28.225 = 1.6:1 (was 2.0:1)
28.325 = 1.3:1 (was 1.8:1)
28.425 = 1.1:1 (was 1.5:1)
28.525 = 1.1:1 (was 1.3:1)
28.625 = 1.1:1 (was 1.2:1)

I'm not certain if I'm splitting hairs here, but the performance
certainly doesn't SEEM to be what it once was.

It has been windy here (40 mph winds were not uncommon in
January and February), and it has been suggested that water
migration in the coax might be a problem.

Any other thoughts or suggestions are appreciated!

Thanks in advance,

Eric W3DQ
Washington, DC

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This Thread
  Date   Author  
09-Mar-2000 David Aslin
* 09-Mar-2000 Eric Rosenberg/Jennifer Gruber
This Author (Mar-2000)
  Subject   Date  
* Odd behavior of my C-3SS 09-Mar-2000