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RFI caused by faulty Cable emergency backup power supply:
This turned out to be a power supply from the cable company. The unit was actually made by Alpha Technologies and it keeps the cable system “hot” during electrical outages. It was very irregular and identified via one-second “ticks” and about every two-minutes the frequency would shift for about 15-seconds and then shift again and the one-second ticks would return. I don’t know the native frequency as it “repeated” every 93 KHZ through wide swaths of the HF spectrum. Credit Alpha Technologies with eventually replacing this XM-2 Inverter Module with a “quieter” one.
RFI caused by an Electric Fence:
The popping you hear is the RFI created by an electric fence as it triggers the High Voltage pulse. If you watch the P3 you will see just how strong a signal it is… Pretty much all electric fences sound like this, a single pulse with some time then another single pulse. Most fences have about a 1-5 second pause between pulses.
Here is the same fence, as viewed on an Icom 7300:
RFI caused by an Electric Blanket:
The horizontal lines are from an electric blanket about 50 feet from the antenna. The vertical lines are a grow light operation about a block away. All on 80 meters.
RFI caused by Ionosonde:
The sloping line is the Ionosonde as it moves across 40 meters. It will manifest itself an a single event woop, when you listen to it using USB/LSB.
RFI caused by under shelf Halogen lights:
The antenna was about 30 feet from the lights.
RFI caused by defective lightning arrestor on a 7200 volt line:
The antenna was about 2000 feet from source. It would look like this no matter what the bandwidth of the P3 was set for on 20 meters.