On 11 May 2014 at 19:35, Don Kirk wrote:
> I think you need to take a step back. No matter were you look you will find
> sources of interference.
Yes, but THIS one is a jim dandy.
> The question is what source of interference is causing
> your problem. Therefore the first questions that I would expect you to answer
> would be as follows :
>
> 1) Is it broadband (like 100 khz wide or more versus located on a very
> specific
> frequency or frequencies), and what is the frequency range that you hear it?
VERY broadband: covers every ham band although there is a very BROAD
peak at about 3600 KHz where it is 20db over S-9. I have taken 18 readings
on every ham band, and other than an anomalous "dip" at 24 MHz (which I
"feel" is caused by either a receiver or an antenna fault), a graph shows a
very gradual fall off in the noise above, and below 3600 KHz. At 30 MHz it is
still S-8.
> 2) Is it on continuous or does it sometimes go away?
24/7/365. I DID happen to catch an approximately 30 second-long dip when it
went completely away, but then returned in force. Furthermore, it seems to be
getting slowly worse.
> 3) If broadband does it go away when it snows or rains?
Absolutely not!
> 4) Is it local (groundwave)?
It appears to be groundwave. Propagation makes no difference.
> 5) What direction from your house is its heading.
I have been unable to exactly determine that, but so far, it appears to be west
of me.
> You are a very smart guy, and if you have not answered the above questions
> then
> you need to do so before you go any further.
See above.
> It does not matter what you think
> the source is at this time, and don't depend on "he said she said" stuff that
> people are saying around town. What matters is identifying what direction it
> is
> from your location and then narrowing it down to within a city block or
> smaller
> via DFing. Until you have done this there is no point wasting resources (FCC,
> power company, etc.).
>
> Note : when determining what direction from your house it is heading you
> really
> need to make sure existing antennas and other metal structures are not fooling
> your DF antenna. I normally walk out to the center of the street (making sure
> I
> don't get hit by a car) or large field with my DF antennas to make sure nearby
> metal structures are not re-radiating the signal and tricking me out (HF
> antennas, rain gutters, metal chimney flue, aluminum siding, house wiring,
> above
> and below grade utility feeds, etc. can couple to your DF antenna or
> re-radiate
> the signal so you have to make sure you eliminate their influence). You also
> need to make sure you determine this heading when you are in eye shot of your
> house (don't drive a mile from your house, get out of the car, and determine a
> heading from that location as it may or may not be the signal that's causing
> problems at your QTH).
I've done all of the above. Still no exact determination of the direction.
Another ham and I are going out next Thursday to try to become more
"specific" about direction.
> I still am interested in hearing and seeing a youtube video of the noise when
> you get the time.
OK. I can do that tomorrow. I have a youtube "channel". Look for W7EKB.
Ken W7EKB
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