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I am plagued here on the coast by the Loran
station on 100Khz located in northen France .The path to my QTH is mainly over
water so sigs very strong even in our band. I needed to reduce the strength of
the sidebands from this station,so I tried a loop ant. this helped but I lost a
lot of coverage due to the double null of this type of ant.(it was not very
convenient to rotate it due to the remote location.However I remembered the
" EWE" ant used effectively on 160 and 80 and have adapted it for
136.The EWE is basically a pair of short verts spaced about one eigth wavelength
apart there is an elevated phasing line between the verts.On 136 the optimum
spacing would be about 750 feet but I modelled the ant for 300 to 500 feet
spacing and got very good plots.the height is not so important( it affects the
sig strength of coufse)but this is very low in any case and needs an amp.Elnec
predicts about 28db front to back and a sensitivity of -42 dbi.
I put this ant up today among the trees! with
the null on the Loran station.This has improved the sig/noise by 10-20db and I
can hardly hear the "galloping Horses )hi.Will need to do lots of on air
tests to comfirm but its looking good.I would not have belived it possible to
get much directivity on 136 but! for details of EWE ant see Low Band DXing by
ON4UN. 73 to all .G3AQC..
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