Dear group!
A few weeks ago, when I did my first test on VLF with my LF-station
antenna, there was a thread dealing with acoustical noise generated when
transmitting on VLF with about 100W.
Meanwhile I was able to increase then antenna-current from 400 to 500mA
and accordingly the "singing" of the antenna is even louder now.
I think I have found 2 different sources of noise:
1. The loading coil which is located behind the house. This is something
I expected.
2. The ends of the antenna wires. My antenna basically has the shape of
a "Y" and so I have got two open ends. One is located in front of my
house and the other is the end of a stub over to my neighbours garden.
The distance between those open ends is at least 40m. The interesting
thing is that the loudest singing appears when you stand right under
those open ends. When you walk from one to the other, the sound would
nearly disappear right in the middle but getting louder as you approach
the other open end.
So if anybody has an explanation for this or has witnessed a similar
thing, please let me (us) know.
73
OE3GHB
Gerhard
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