[OFARC] Reduced RFI at my house

[ralph phillips]

The recent short time power outage at my house has kicked off a discussion of RF noise levels.
Some of us have noticed a reduction of noise on HF bands since the 18-wheeler took out some electrical gear near the intersection of US59 and Beltway8.

I looked back in my notes to see how much of a noise reduction may have occurred.

2011 s9+ noise floor on 40m, 20m, 10m (Measured on S meter of Kenwood TS140; 1985 vintage radio)
I filed with CenterPoint and they found a problem in my neighbor’s house (bad wall wart).
Noise went down to s5

2012 noise was back at s9
I called my neighbor and he found a bad computer power supply
Noise down to s5

2016
CenterPoint replaced all the transformers and underground lines in my neighborhood
Noise floor went to s3

2018
New radio… IC7300
Noise floor at S5 again, RF gain can go to 20%-30% before the spectrum scope turns white
I traced the source of noise to my back neighbor.  Her son told me they recently got a new washer.  No luck in discussion the issue with the haus-frau.
see photo below – note the periodic bars of noise across the band. 

2019 noise floor about the same, with some periodic increases

2021
During the 1 hour power outage, battery power;  noise floor was s1, RFI gain could go to 70% to pull out faint stations
After the repairs and power back on I stayed on battery for a week; noise floor about S3 and RF gain can be raised to 40% before the spectrum scope goes white.
Noise increased to S5 during the evening 2 days later but went back down the next day.  (I am guessing a neighbor was doing laundry.)
Switched to a power supply (heavy iron type) plugged into AC and got same noise floor results.
Switched to a newer power supply (switching type) and same results  (so not a problem in the power supply)

Conclusion…
There has been a reduction of RF noise in my area since CenterPoint repaired some equipment approx. 1 mile from my house (straight line).

Watch the noise at your station.
If you see an increase over time, or an increase during wet weather compared to dry weather, call CP.
They will NOT come out to y our house unless you have already checked the systems in your home by turning off power at your breaker box main and running on battery.  That gives you and them a base line and confirms the noise is not coming from your house.   
Have notes of your RFI measurements….. noise floor S# (or something equivalent), time of day, type of noise, weather conditions, bands on which you have a problem.

Ralph
KE5HDF
Sent from Mail for Windows

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