Antennas and noise
- I wish to report my experience with noise generated by antennas.
When I was young (60's), in windy days it was hearable a boring
sound of not well ideintified source. Nobody in my family but me
realized that the cause was the steel tube supporting the TV
antenna, which worked as an organ pipe. As far as I could remember,
the pitch was in the order of 300 Hz, to give an idea. I solved the
problem plugging the tube ends.
More recently (80's), in my own house, there was a similar problem.
The tone was very low, and was hearable even in the presence of a
just delicate breeze. The tube was 6 meter long and 5 cm (2inch)
inner diameter. It was the mast of a ham antenna. Again I solved the
problem pluggin the ends.
A couple of years ago, my brother told me that in the nights he was
hearing an absolutely intolerable low pitched hum. Impossible to
sleep. I asked him to notice if that occurred in windy or breezy
nights. After a week or so he confirmed. So, I plugged the ends of
his antenna's mast, but this didn't solve the problem. After
thinking a lot about, I suspected of the steel wire braces
reinforcing the mast: they were too tight, and worked as harp
strings. The problem was definitively solved by loosing a bit the