The ground signal is an illusion. I have made many measurements by
vibrosensor. The level of vibrations is very low and they haven't
correlation with the hum. In fact the feeling of vibration is in the
human's body. It is produced by the hum, but it is inner, not outer.
In my opinion it isn't good idea to mask this feeling by artificially
created vibrations in the bed. It is more harmful than the hum. Of
course you decide.
--- In email@example.com, "mack_colin" <mack_colin@...> wrote:
> The ground signal of the HUM through the pillow in my wooden frame
> has been driving me nuts recently.
> I am now trying one of these clip-on mains operated fans (about 6"
> I have clipped it to the wooden bedstead (at the feet end of the
> thus creating a vibration through the bed frame and up through the
> pillow, this seems to be masking the HUM effect quite well.
> I will have to give it a month or two to see how good this method is.
> Cheers Colin, Scotland.