[RFI] Another Solar Panel Interference Case

[Jim Brown]

What many hams continue to miss is that for about the last 20 years, the 
MF and HF noise floor has increasing been dominated NOT by that 
generated by the power system, but by switch-mode power supplies, power 
control electronics, and solar systems. when I moved from Chicago to 
NorCal in 2006 in the midst of a solar minima, I could EU several nights 
a year on CW. Over the past 5-6 years, also a solar minima, and with 
slightly improved antennas, I've HEARD about six CW signals from EU, and 
only two heard me. Now I can work EU only using WSJT modes, and I worked 
none this season. The difference is increased noise on both ends of the 
QSO, and that FT8 can work about 10 dB deeper into the noise than CW 
with great ops on both ends.

73, Jim K9YC

On 4/5/2022 12:31 PM, EDWARDS, EDDIE J wrote:
> I suspect this is due to (1) shrinking markets in AM radio and OTA television, (2) Digital television changes so any existing OTA viewers don't even realize they have powerline noise, and (3) increased noise floor for HF hams hiding the powerline noise levels reported in the past.