[TowerTalk] Ground rod placement???

Malcolm Clark rudder1@ibm.net
Wed, 29 Apr 1998 09:07:36 +0000

David E. Shelton wrote:


> I ask all this because I get complaints now when running >60 watts
> output from some neighbors and one day I would like to run an amplifier
> with about 500 watts or so. I understand that the RFI is coming from the 
> antennas, Force 12 C4 and home brew wire antennas off the tower, and not 
> the rig in the basement but I want the station to be as RF clean as
> possible.


Your feedline(s) may be radiating due antenna imbalance.  Suggest you
try a choke balun at the feedpoint.  Naturally the shack should have a
good ground as well--for safety at least.  However, I doubt that curing
the feedline radiation will in of itself solve the RFI problem.  A
radiating feedline radiates on the same frequency as the antenna.  It
should have no impact on RFI.

The only way I could see for an antenna to generate RFI is thru
intermod.  For that to happen you would have to have a bad connection
that formed a non-linearity, plus there would have to be the presence of
one or more additional signals to mix with your TX freq to generate the
intermod product(s).  If the problem is at your end, it is most likely
in your rig.

Good luck.

Malcolm KR4HP

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