Hello Laurence,
Thank you for sending this information to the list.
Your 30 - 40 db noise attenuation agrees very well with my own findings at
400 kHz: 40 dB for a concrete building and 32 dB for a brick wall house.
The clue is the walls attenuating the noise from inside the building.
Thus at LF all is not lost for the city dweller using an E-field probe!
You are the first one who carried out the same research as I did (as far as
I know of) and I am very pleased to have the results reproduced under such
difficult circumstances.
It might be quite educational to try a loop at the same location.
Thank you for your efforts.
Best regards,
Roelof Bakker, pa0rdt
|