I recently put up an inverted vee for 80 and 40, hung off the top of my
LM-470E 70' crank-up tower. I noticed that when I went to listen on it, I had
a horrendous 20 dB over 9 noise level that was not there on my other, lower
I tried putting in 10 dB attenuation on the TS940 and the problem went away!
This antenna has proven to be a good performer, as long as I put in 10 dB
attenuation on the 940. This holds true for 80m as well as listening on 20 and
The other antenna, which does not exhibit these problems, is a Hygain Explorer
14 with a 40m kit mounted on a tripod on the roof at about 25 feet. (BTW, the
inverted vee whips the shortened 40m rotatable dipole by as much as 2 S-units,
I know that there is a strong AM broadcast station about 2-3 miles from me,
which has interfered with the telephones, but I haven't had any trouble from
it in a couple years.
I am assuming that I am experiencing an overload situation, which must be
pretty severe, since when I add the attenuation, the S-meter falls from 20 dB
over 9 to a more normal noise level of S-2 or 3. The overloading signal must
be really driving some receiver circuit "crazy" to generate that much
I am interested in any opinions on what is going on here. Is my 940 broken
(bandpass filters not working, other circuit problems)? I am considering
adding a high-pass BCI filter to see if that helps. Any recommendations on
If this is not the right place to discuss this, sorry. Thanks for any ideas.
K7NT@aol.com or MConatore@yahoo.com
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