Hello Roelof
You said:
One of the tests I did was on the second floor of a large concrete
community
building.
I have performed some height test as well and found the following figures:
height rel. dB
=================
1.2 m / 4 ft 0 dB
2.4 m / 8 ft + 4 dB
3.6 m / 12 ft + 6 dB
4.8 m / 16 ft + 8 dB
Shielding by bushes in my garden has also been noted. I had to raise it
above these to restore a good s/n ratio. On the other hand, at an open
field
near a lake it worked first class 2 metre high and raising it improved
signal strength but not the signal to noise ratio.
These results are in line with tests done by G3GRO a couple of years ago
with a short electrostatic whip antenna.
I have the amplifier and coax voltage supply board for a electrostatic
antenna used at the Decca transmitter sites. The original antenna was a
copper cylinder fixed only a metre or so above ground. I am not sure what
they were used for - I guess Walter would know.
Peter, G3LDO
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