I have noticed a strange 'group' of signals mainly centered on the 40 meter
band. The signal sounds a bit like power line noise but may actually be at a
higher frequency-kind of a 'growl' more than a raspy 120 hz . The 'noise'
seems to peak every 140KHZ and is detectable from below 6 mhz to about 8
mhz-this range may be greater but I haven't tuned more spectrum yet It does
appear to fade quickly as the freq increases from 8Mhz on. The strongest
peaks are about 20 over s9 in the 40 meter band (which may be due to a
resonant antenna,etc) The noise is relatively narrow band at about 5 KHZ max
before beginning to fade out. Using 500hz filters in the AM position the 40
meter peaks seem to be at (6880), 7020. 7160, 7300. The frequency of these
peaks varies over time by about 5 khz. This interference disappears once in
a awhile but I have found no apparent patterns
I have killed every circuit in the house and am pretty sure it does not come
from inside the QTH (it's always possible I overlooked something) . The next
step is to put the 706 in the truck with the 40 meter ant and 'cruise' the
Any wisdom or ideas will be greatly appreciated.
Merry Xmas and Happy New Year!
zone 4 and 8/ohio/EN81oj
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