[Elecraft] Help identifying this RFI

[Wes (N7WS)]

Thanks for the many replies.  I'll try to address all of them in one message.

First, I agree that this sounds like a powerline problem.  I've seen many of 
them in my 57 years of hamming.  What makes this different, and the reason for 
my call for advice, is the periodic nature of the problem.  Actually, the 
problem is nearly continuous but is interrupted periodically.  When I first 
started paying attention to this, I saw that the quiet periods were spaced about 
six minutes apart.  This led me to think there is a timer involved. Grow lamps 
sprung to mind, since the "wild west" nature of this area makes that a distinct 
possibility.  That said, my understanding is that these are on for much longer 
times.

Regrettably, it's also our time for thunderstorms so my antennas are often 
disconnected so a good timeline is problematic.  I do believe after some more 
listening that the periodicity is less uniform than previously believed.  Maybe 
it's totally random.

Some more data points:

1)  I have opened the main breaker to my house and run the K3/Laptop on battery 
power with no change.

2)  To the best of my knowledge there are no electric fences here.

3)  My immediate neighbor to the north happens to be a welder, but he's not the 
culprit.  He's put his wife to work and he plays.

4)  The power feed to my house is underground.  The nearest power pole is ~450 
feet away from my tower to my WSW.  The power line runs N and S from that point 
with another line intersecting at that pole and running to the west.

5)  To my north there are two E-W feeder lines tapped into the N-S line.

6)  One supplies my immediate neighbor to the north (the welder) via a pole 
mounted transformer.  This is 350 feet due north of my tower.  I've strummed the 
guy wires to these poles without noting any change.

7)  A second 1000 ft E-W line feeds another transformer that is 850 feet NE of 
me.  This transformer appears to have some oil leakage, but shaking the H out of 
it via the guy wires makes no change.  The power company guys say it's OK.

8)  Although we are entering our Arizona summer "rainy season", to date I've 
recorded a couple of hundredths of an inch.  The noise issue predates this. Our 
power poles never swell, they just get skinnier and skinner.  Years ago the 
power company tried to fix some noise problems I was having by replacing the 
plain staples that attach the ground wires to the poles with barbed staples that 
wouldn't (so they thought) pull out.  Furthermore, the staples were copper 
plated and the ground wires are aluminum.  Eventually, the copper went away and 
now the staples are rusted steel.

9)  My "sniffing receiver" is limited to 30 MHz but I have a lead to someone 
with more appropriate equipment, as well as expertise.

10)  The Elecrafter's will understand this, I have a new K3S almost ready for 
delivery (credit card's been charged) it would be nice to be able to hear 
something on it.


On 7/1/2015 3:31 PM, Wes (N7WS) wrote:
[snip]