[RFI] A reply for the Power line noise experts

[N1BUG]

Thank you Michael. Your advice is greatly appreciated. Following 
this same procedure which you explained to me several months ago I 
successfully located numerous sources which have since been fixed. 
The method works great and has been very helpful!

Evidently this last small area exceeds my ability. Constantly 
changing strength of the noise has me at wits end. As soon as I 
eliminate the weaker signal they both disappear. In the time it 
takes to move from one set of poles to the next the strength of the 
source is guaranteed to have changed. It is virtually guaranteed to 
change in the second it takes to swing the yagi from one pole to the 
other. I can't get a consistent or repeatable reading anywhere. If 
peaks occurred with some regularity it might help, but they don't. A 
given peak level observed at one instant may not be seen again for 
hours. I have made dozens of attempts and still do not know for 
certain which pole is the source.

It looks as though I will have to live with this one unless I get 
better equipment or the noise changes in some way that makes it 
easier to locate.

There is just one house with a live electrical feed in that stretch 
(plus two vacant and disconnected).

There is one final bit of purely circumstantial evidence. I realize 
this doesn't prove a thing. Even if it did, I would still be left 
with 7 poles and no way to be certain which of them is responsible. 
There has been only one fair weather day in the past 8 months when 
these two noise signatures were not present. The 5 hour absence 
coincided to the second with opening and closing of cutouts on a 
section of the 46 kV line. The 13 kV line remained live during this 
time.

Paul, N1BUG



On 12/27/2012 05:15 AM, RFI Services' Michael Martin wrote:
> If you receive the signal across 7 poles, you know the signal will be
> stronger at the source pole. Reduce your gain to eliminate the weaker
> signals. Stand at least 20 feet away from the lines at equal distances from
> two poles. Pointing your yagi back and forth as you reduce your gain to
> eliminate the weaker signal. Once you determine which of those two poles has
> the stronger signal move in that direction and perform the same test between
> the next two poles. Then repeat.
> The fact that you don't receive the signal at UHF is not a good sign for
> arcing. However it is a good indication of either further away or inside one
> of the houses connected to one of those 7 poles. That would also explain one
> of several reasons for no success using ultra sound. The first reason for a
> lack of Ultra sound success is lack of sensitivity. This one is  for sure.
> Remember, ultra sound is your last step and it can only be as successful as
> the proceeding step. Do Not use ultra sound unless you are 100% positive
> about the structure containing the source. Don't put your foot before the
> crutch! Also, Ultra sound on a windy day is a mess and very un reliable.
> That's like using it while someone is shaking the pole. See what I mean?
> Use my "how to locate the residence" instructions. It works!
> (http://www.rfiservices.com/residence.htm )
> Look out for the next edition of the ARRL's RFI Handbook.
> Merry Christmas,
> Michael C. Martin
> RFI Services
> 6469 Old Solomons Island Rd
> Tracys Landing, MD 20779
> www.rfiservices.com
> 240-508-3760
>
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces at contesting.com] On Behalf Of N1BUG
> Sent: Wednesday, December 26, 2012 5:19 PM
> To: eddieedwards at tconl.com
> Cc: RFI at contesting.com
> Subject: Re: [RFI] Power line noise question for the experts
>
> Ed,
>
> It is one of the DIY "kit" units. However it is the recently released RX3,
> not the older RX2 or RX1. Under controlled test conditions, this unit picks
> up a spark at 100+ feet vs. 35 feet for the previous model. What that
> equates to in terms of sensitivity specifications I leave to brighter minds.
> (Disclaimer: while I do not profit in any way from sales of this unit, I did
> play a minor role in the R&D process)
>
> The power company has checked that pole twice with a Radar Engineers model
> 250 without hearing anything.
>
> I'm now questioning whether in fact I have the right pole. It is hard to
> have faith in my findings on those windy days when I could barely hold onto
> the dish.
>
> 73,
> Paul N1BUG