See below... 73, Guy.
On Wed, 23 Sep 1998 22:20:45 -0700, zeitler@ibm.net wrote:
>
>Colleagues,
>The determination has been made: I will be forced to run a form of an
>inverted L for 160. I will be using my neigbhors 45 foot pine tree to be the
>main support. My pine tree that is located in the front yard will be the far
>end support. There is (very) roughly 90 to 110 feet in between.
>
>My question: is a 1/4 wave the optimum length for an L? Some folks have
>suggested going with 3/8 wavelength instead.
If you just use it for 160, the length is not so important as the
ground & whatever radials you can install. The ground and radials will
be 90% of the performance. The lengths you have quoted would put the
current max in the middle of the vertical section which is cool.
If you use it for 80/40, then the length will change
matching/performance drastically on 80/40.
>It will not be a symmetrical L. The vertical part will not be 90 degrees
>perpendicular to earth. It will be more like 50 to 70 degrees approximately.
>So the L will look like this:
>
> __________
> \
> \
>Vertical angle will be slightly less than this
>
>Approx. 45 to 60 feet vertical and I can run around 100 feet horiz.
>
>So is it better to run it longer than a 1/4 wave?
>
>Also I would like to use this as an all band antenna. For those of you who
>do have L antennas have you tried them on 80, 40, etc??
You have not told us where the base of this antenna is, eg at the
shack, where you can attach a tuner directly to it, or at a distance,
and you were just going to hook a piece of coax to it, or what...
If it's at the shack, and the tuner can stand it on those bands, then
length still doesn't matter. If it won't tune, then shorten the
horizontal piece a little bit at a time until it will tune all bands.
Before I get into a discussion of remote matcing of an end-fed
160/80/40 L antenna (which I have and works very well), would want to
know whether it applies to your situation.
>
>Comments encouraged.
>
>Lane
>KM3G
>San Diego
Guy L. Olinger
k2av@qsl.net
Apex, NC, USA
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