[SADXA] [Elecraft] Help identifying this RFI

[k7bhm at cox.net]

Wes............Possibly fluorescence......The inconsistent audio pattern is a clue.

FWIW...........Bob - K7BHM


---- "Wes (N7WS)" <wes at triconet.org> wrote: 
> 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]
> ______________________________________________________________
> SADXA Website http://www.sadxa.org
> 
> SADXA mailing list
> Home: http://mailman.qth.net/mailman/listinfo/sadxa
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:SADXA at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> You can support qsl.net: http://www.qsl.net/donate.html