If you suspect an appliance, sniff around with this:
https://www.amazon.com/Magnetic-Conduction-Radiation-Circuit-Antenna/dp/B0CBMN6PY1/ref=sr_1_1_sspa
The noise is way too strong for these, also they are far too broadband.
I built a tiny antenna like this resonant at 29.5MHz:

With this I discovered it is not just one inverter... It's all of my solar inverters...plus Poe switch and the laptop's PSU.
While I can easily filter the laptop PSU and the PoE
Switch uses łan cables as antennas (they respond to 5 turns on a ferrite toroid very well) the solar inverters is a different story.
For some reason they generate most noise even when doing absolutely nothing. There is a tiny switch mode PSU in them. I suspect the actual inverter modules are well designed.But that PSU may have been an afterthought.
Also, I tried to find out which cables emit the most RF and very weirdly it is theDC cables to the batteries. I measured -47dB with this antenna touching and tinysa (lna on). (despite not using the battery at all! Inverters are in AC pass through mode for most of winter and neither charge nor draw much current from the battery. Maximum of few amps )
Then it's the AC neutrals with its -51dB, then it's AC live out at -52dB and AC live in at -53dB. Finally solar wires are around -57dB and ground is around -71dB (background is -120dB).
Ive ordered quite a few of material 31 ft240 cores to test . But now I wonder if my DC battery wires will not just saturated these ferrites. The current there cab be in the hundreds of amps (150 charging per each of 3 inverters, discharge up to 250A per inverter).
I searched "entire Internet" and I've not found how to calculate a one turn saturation current on aFT240-31 amidon core. If anyone knows let me know please .