> Dennis (DL6NVC)
> Please could you try your loop away from the tree. Preferably more than 2
> metres. I have found severe bio-electric(?) noise from trees from 3.5 to
> 500MHz.using loops, whips and UHF Yagis. The noise drops to almost zero
> if
> the tree ambient temperature is below about zero Celsius.
> Mike - G3LHZ
Hi Mike, this is a really amazing statement! I'm going to investigate this
somewhere in the nature, kilometres away from cities and villages!
Yes, the tree obviousely will act as a "black body radiator" at (hot sunny day
today) >300 Kelvin. But does this matter to 500kHz or shortwave? I don't
believe it. But with UHF and SHF weak signal communication, this thermal noise
would clearely be an important issue.
Since yesterday, I actually have 3 loops up and running:
1. 10m loop, linden tree, nearest end about 5m from the house, abt 15m agl
2. 10m loop on the balcony, outside but close to the house
3. abt. 12m indoor loop
I must tell you, that the loop inside the linden tree delivers by far the best
signal-to-noise, the balcony-loop is worse, and the indoor loop is even much
much worse.
The broadband noise seems to travel along the mains wiring. When I simply touch
the soldering iron, when I connected the central heating as "ground", this all
causes increased noise.
Think, some or several of my neighbours are using powerline communication
systems.
vy73
Dennis
DL6NVC
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