I have forgotten to say that I had even dug for myself a special "command room" under my company facilities. (I am partially owning the company so I could afford it.) The room is 4 meters under the ground level, naturally, it has no windows and has artificial ventilation. HF readings are very low, but LF sometimes shows up to 1 mG which is rather high for me, and it comes from the street installation, probably due to stray currents. I am not completely satisfied even when there are no LF readings, I don't know what is the reason. Anyway, it has some "underground feeling" (independently of having no windows, it just feels like that), and it is a bit claustrophobic.
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