Hi Joe if you look back to Jim's field strength measurements he found that
he got anomolous results when he was near overhead lines (power or
telephone) that ran away from is TX site. There is no doubt that these go
act as "guide" for RF, but we have all measured substantial reductions in
ground loss ( as measured by bridge) when the mains earth is included in the
grounding regime. (This does not work for everyone though) If this was the
case I would have expected your antenna current to increase when you connect
the mains earth.....strange.
Cheers de Alan G3NYK
----- Original Message -----
From: "Joe Craig" <[email protected]>
To: <[email protected]>
Sent: 09 July 2005 12:50
Subject: LF: Mains Earth
Dear Group,
Thanks to Alan, Laurie and Wolf for their info on the mains earth.
At this station, there is one transmission line that runs in front
of the house and another about 1 km to the south that runs
roughly perpendicular to it so the mains earth grid is a bit sparse.
When doing mobile FS measurements, I noticed that the signals
were always stronger near the mains lines and suspected for a while that
the signals were being conducted along the lines rather than being
radiated. This was put to rest when Alan copied the sigs 2 years ago.
Thanks to G3AQC and Hartmut for the signal reports.
73
Joe
|