For several weeks I have been plagued with a comb of extremely stable , clean
RF carriers spaced exactly 4 khz.
At various times the comb might be only 4 or 5 carriers - at other times it
will cover from about 1710 to 1910 khz .
Day after day these carriers will be within a few cycles of the same
frequencies . Typically for instance
1811.955 , 1815.955 , 1819.955 , 1823.955. For a few days when this started
appearing only three to 5 of these
carriers would be there. Then some nights or days there would be a comb
covering 1710 -1910 or so ..
One night I returned to 160 from 40 and was happy to see no carriers at all. I
preset the Alpha tune/load
kicked it on and maybe 3 to 5 seconds of carrier for a touch up. When I stood
by , the band was full
from 1710 to 1910. - carriers at roughly -80 dBm plus minus 5 dB or so.. The
first time
this happened I was not 100 percent sure I had just not noticed the carriers
had popped on before
I fired up. (These carriers appear to stay on for a day or so after the event )
.
This morning , I checked and the band was clear of these carriers . I keyed the
K3 at about 33 watts
a couple times and two carriers popped up 1831.950 and 1827.950 . I keyed again
for maybe 2
seconds and another carrier popped up at 1823.950 then sent Vs for about 5
seconds and another
carrier popped up at 1835.950. As I kept this up each time another carrier or
two would show up
1839.950 etc up to 1851.950 . I just looked and now after about an hour more
have appeared
every 4 khz up to 1817.950 . Strangely the two at 43.95 and 47.95 have dropped
about 8 dB
as has 55.95 ..
WOW - was going to pop on te ALPHA but just for hell of it sent some Vs in the
middle of the
comb - nothing changed - moved below the lost carrier sent a couple V and
another carrier
popped up. Each time I moved down another would pop up .Ahaa - if I key at
freqs just above
the comb - new carriers start popping up but I do not have to move freq -(found
same was true for
low side , carriers popped up below 1800 keying around 1810. )
OK after keying at 1500 watts it spreads for 1727.950 to 1891.950 . I might add
that my 160 loop will null
these sigs NE/SW and that is NOT pointed at my house. I have probed all around
the house - turned router
off . DirecV etc etc . That same heading also drops a broadband noise 10 dB at
that heading .
I built a ferrite rod antenna that tunes 160 so will see if I can snoop outside
some .today with my R10 rx. .
Hank K7HP
What am I looking for ?
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