[RFI] Noise centered around 20 meters

[Gary Johnson]

> From: K9MA <k9ma at sdellington.us <mailto:k9ma at sdellington.us>>
> To: rfi at contesting.com <mailto:rfi at contesting.com>
> 
> The clincher, in this case, is that the source goes silent when it is 
> wet, returns when it dries out. 


We had persistent power line noise at N6RO for two years, and indeed it went silent whenever it rained. Eventually the PG&E guy came out and precisely located it (he was a ham, as it turned out). Root cause: A cracked insulator on a 13 kV line. Rain would apparently suppress the corona discharge. No issues after the equipment was replaced.

The character of the noise was a broad-banded and erratic sizzle, on all the low bands. Mostly looked like white noise on the waterfall. In contrast, the noise caused by my neighbor’s infamous LED lights, which have no filtering on the AC line side of their switchmode converters, was a powerful 120 Hz harmonic buzz from dc to daylight.

Gary NA6O