Hi,
My son is a youth operator and recently obtained his General ticket. Unfortunately, he doesn't live with me; he lives about 3 miles away with his mom (my ex).
He is running an ICOM-7300 located in the basement of a two-story house. He has a G5RV antenna strung between the back of the house and the end of his mom's property.
He observes strong carrier signals on the waterfall spaced approximately 31kHz apart on the 80m band - but not on 40m or 20m. This interference appears only on 80m. He doesn't have any problem on 40m or 20m. But on 80m, this interference is spaced evenly at 31khz intervals and - what's worse - it drifts across the band. So even if he chooses to work on a frequency that appears to be clear of the interference, within a few minutes the carrier will drift across his chosen frequency and render it unusable.
I'm guessing it is RFI from something in his house, or in a neighbor's house. Actually, I'm hoping it is in my son's house, because then - once we locate the source - it will be relatively easy to fix. But if it's coming from outside the house, it will be much harder to pinpoint the source and mitigate.
So, for the past couple of days, he and I have been trying to troubleshoot this and locate the source of the RFI. There's a big plasma TV in the same basement room as his rig, and that was my first suspect. So he unplugged it, but the RFI was still there. Ditto with his Wii game unit also in the basement. Ditto with the remote-controlled LED lights in his basement. Unplugging these items did not eliminate the RFI.
I also suspected the monitor for his gaming PC which he has upstairs in a second-story room in the house. He switched off the power strip, so no power going to the CPU, the PC or the attached printer. It did not eliminate the RFI.
I also had him unplug the router for their internet/WiFi service. No effect.
At this point, I don't really know what else to check. They do have another TV upstairs in his mom's bedroom, and an AppleTV device. The mom is a musician, so I suspected she might have had some guitar amp or other such device causing the problem, but he reports that none of that stuff is plugged in at the moment.
I asked him to try unplugging those later today and report back to me. But if it isn't either of those items, the only thing I can think of is perhap's his rig's own power supply unit, which is a Powerwerx SS-30DV. I've got a battery, so I'm going to go over there, maybe tomorrow, to see if the RFI is still there if we operate the rig off battery power. But I'm convinced that there is some gizmo in his house spewing RFI that I just haven't thought of.
Any ideas?