Not too long ago I had rebuilt my 24v battery pack for my PRC-104 with NiMh batteries, what I had found when the charger was working was the noise was atrocious, once battery was charged the noise would subside but I guess it was never totally gone. So one day when all of our power was down for a tree on the line I tested the radios with battery and found zero noise levels, none what so ever, so it lead me to start searching a bit deeper, looking at TV noise, routers etc, but still no luck nailing the problem.
So I continued to do a bit of more pulling of plugs and seeing what and where the noise could be coming from. I own many types of battery packs and chargers, batteries for radios, cameras and scanners, so I had to start one at a time. I leave the chargers always plugged in ready to go, so never really anticipated that this would be my issue. But I was very surprised when I found two of my chargers that were the problem.
The one charger was indeed my smart charger for my NiMh battery pack for my PRC-104.
The other charger that turned out to be an issue was a Duracell battery charger that I use for my camera batteries. It was amazing at how quiet things got once they were unplugged. The noise on my VX-1700 with these chargers plugged in and not being used would be a solid 9 and more, once I unplugged both of these units the noise dropped to a 3 and I could hear stations once again. I need to look at some of the other chargers in the house that are used for routers and other items in the house.
The NiMH charger when charging makes all bands useless when it is actually charging, the charger for my VX-1210 is the same, very loud noise levels emitted from these units.
So I am glad I did a bit of unplugging and checking and have found some of the issues that have plagued the home shack. Many of today's electronics is just plain noisy and does emit all kinds of stray RF and noise.