In a message dated 99-10-19 10:54:04 EDT, W4nf writes:
> My C3E is now assembled and ready for tramming up on Sunday. Can someone
> explain in a little more detail this fix to secure the location of the
driver
> cells on the antenna. Once it is up at the top of the mast it is going to
> stay there awhile. I would think that using some sort of non metallic flat
> material that could be placed on top of the two ten meter drivers and the
20
> meter driver could then be drilled and riveted in place to maintain the
> required spacing. Maybe the spacing device should be placed about half the
> distance out the ten meter elements. The 20 meter driver starts its droop
> from the boom fairly rapidly so any mod to secure the drivers in relative
> position to each other would probably have to be located where the 4
elements
> are in the same relative horizontal plane (prior to the 15 or 20 meter
> drivers starting their droop). Does the 15 meter driver also need to be
> secured? I'm just throwing out ideas. Has anyone completed such a mod
and
> if so how did you approach it. I would like to implement it as this seems
to
> be an area of concern with detuning of the antenna.
Physical placement isn't critical and neither is the configuration.
The factory uses a flat piece of a non-conducting material and a couple of
hose clamps. I would recommend this method over riveting something. The
hoseclamp method is stronger and more reliable.
The driven elements that are the closest together are the critical
ones. Any change in their proximity is what causes the swr change problem.
Cheers, Steve K7LXC
Tower Tech
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