From: thekmanrocks@gmail.com   
      
   On Tuesday, July 19, 2022 at 7:04:47 PM UTC-4, Dave Platt wrote:   
   > In article ,   
   > Chris K-Man  wrote:   
   >   
   > >Should an electrical service mast like the one I linked to cause that level   
   of EMI?   
   > By itself, no. It ought to be a fairly passive pass-through for AC   
   > current, with no mechanism for generating RFI. If there's a loose wire   
   > or other bad connection, it could be making noise (and possibly overheating   
   > and creating a safety hazard).   
   >   
   > Seems to me there are two possible sources of the RFI you are suffering:   
   >   
   > (1) Industrial equipment on that line (welders, big brush motors,   
   > switching power supplies) which are generating RFI internally and   
   > feeding it back into the mains. Here in the US, "Class A" equipment   
   > (for use in business environments) is allowed a lot more RFI leakage   
   > than "Class B" (residential), and industrial equipment is even worse.   
   >   
   > (2) A physical fault in the mains wiring, which is causing arcing and   
   > sparking, corona discharge, and so forth. Two fairly common problems   
   > on power distribution poles are bad insulators (with electricity   
   > arcing over them) and loose or defective ground connections. Arcing   
   > in a circuit-breaker panel (e.g. a breaker going bad) could have   
   > a similar effect.   
   >   
   > In both cases the noise can travel quite a long distance along power   
   > wiring to the point where it troubles you.   
   >   
   > There are a few ways that can be used to track the location of a noise   
   > source or fault of this type. Corona discharges and arcs often   
   > generate a lot of ultrasonic noise, and there are ultrasound receivers   
   > with directional microphones which shift this noise down into the   
   > audible band. Arcing and corona can also generate noise up into the   
   > VHF band which can be tracked using a receiver and a directional   
   > antenna (e.g. a small hand-held Yagi). A spectrum analyzer hooked to   
   > a directional antenna can be a useful tool as you may be able to see   
   > specific noise lines bouncing up and down.   
   ____________________   
   But close to that mast, in this apartment's bathroom, is where the interference   
   is strongest, out to perhaps a ten foot radius, which covers most of this   
   bathroom.  Beyond that, the interference is, at worst, negligible.   
      
   And I understand that the head of the service mast - the part visible above and   
   to the left of the bathroom window, is only part of the package.  I will take   
   outside   
   a small portable radio, and walk around within 8 feet of the meters at the   
   base of   
   the service mast, and see what happens at the frequency of the AM station I   
   listen   
   to.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)