Re: Searching for Noise (i.e., Samples Thereof)

Posted by Dave New, N8SBE on Feb 19, 2019; 7:37pm
URL: http://elecraft.85.s1.nabble.com/Searching-for-Noise-i-e-Samples-Thereof-tp7648980p7649076.html

Thanks for all the tips, guys, especially the MFJ meter references.  I
have their ultrasonic sniffer, which helped me point out to the local
power company some dangling insulators.

I have tracked down some on-premise noise sources in the past (in no
particular order):

1) The clock on a Mr. Coffee coffee maker.  It put out a buzz-saw that
could be picked up directly for some distance, plus it coupled to the
power line, for an extra boost of signal goodness.

2) A porch light day/night sensor that screwed into the bulb socket.
This was amazingly noisy, and only came on at night (natch).

3) A laser printer switcher power supply.  'Nuff said.

4) A doorbell transformer, likely as old as the house (built in 1954).
It was mounted on the side of a junction box in the basement, and was
exceedingly difficult to track down, as none of the breakers, except the
main, would turn it off. Found out later that the previous owner had
paralleled two breakers in the panel, likely because he kept tripping
one of the circuits in the kitchen or bath -- the effect was that
turning off one or the other breaker had no effect on either of those
circuits.  Thus they were 'mystery' breakers until I pulled the panel
cover and discovered what had transpired.

I've since had an electrician put an extra panel put in, and some
circuits split, because the original panel was completely full with
duplex breakers.  Making plans now to put in a whole-house generator.
Got the go-ahead from the XYL.  She is tired of all the power outages
we've had in our neighborhood over the last 2-3 years.

73,

-- Dave, N8SBE
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