At 10:55 AM 7/9/2006, John Cowan wrote:
>I would like to have an antenna for 160 meters this fall. I have a 68 foot
>tower that I can use to hang an inverted L from or maybe even shunt-feed.
>I would like suggestions from the group. I live on a lot about 135' by 145'.
John,
W0YVA, who hosts the Collins East Coast First Wednesday net with his KW-1,
and who also works 160, gives me this advice on a transmitting antenna for
160 and 80
Fellows with lots of experience on 160 and 80 claim very good results with
a simple dipole antenna fed with commercial ladder line. The thing is 95
feet on each side of center and put up as high as possible. Wiggles and
bends in the elements do not matter. Dropping the ends down if you don't
have enough space does not matter. Height does matter some, so the higher
the better. A balanced tuner is essential, and you can make one fairly
easily. 7 turns on the input link which is series tuned with a moderate
spacing capacitor. The main coil is tuned by a high voltage cap and is
about 2" in diameter and maybe 10 inches long. Clip leads select the
right two tap points on each side for 80 or 160, Once you antenna is up,
you find the right taps and leave them alone. Roller inductors and vacuum
variables are simply not required. A high voltage, high current RF switch
is not needed if you don't mind using the clip leads to change bands, or
have some banana jacks/plugs to do the job.
Note that this thing is 190 feet end to end, but just put it up as high as
you can and let the ends fall down toward the ground. Bends toward the
ends of the thing would likely cause no trouble. If you can make it into
a Z shape to fit your lot, go ahead.
Do not use traps. Do not use an inverted L. Do not spend big bucks on a
fancy tuner. Do not worry about sags, slopes, wiggles or ups and downs.
Do use ladder line to feed it, and build a tuner.
Roy
- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
NEW: 13033 Downey Mill Road
Lovettsville, VA 20180
Phone 540-822-5911
Cell 301-928-7794
Work: Voice: 301-975-3254, Fax: 301-948-6213
roy.morgan@nist.gov --
Old address: 7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828
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