[Icom] ANTENNA TUNING PROBLEM

Wed, 31 Jul 2002 20:03:19 +0200

...well, yes. A great variety of noises are proapgated aroung what we call
ground loops. These are cases in which there is more than one ground path
between two given points: for instance the power ground through the  chassis
from battery and radio and another one from the antenna's ground point to
the radio. These enclose an area  that behaves like a loop antenna, and also
carry the difference voltages between their respective ground points.
Including such a ferrite choke introduces a large RF impedance in series
with the loop and reduceses the noise carrying current without affecting the
RF energy in the cable. It leaves only one path to RF ground for the current
to follow.
		73:
		Alex	4Z5KS

-----Original Message-----
From: Davies, Doug A FOR:EX [mailto:[email protected]] 
Sent: Wednesday, July 31, 2002 6:52 PM
To: '[email protected]'
Subject: RE: [Icom] ANTENNA TUNING PROBLEM

In the process of trying to eliminate ignition noise from my MKIIG, I was
told to wrap a couple of turns of the coax feedline through a split ferrite
bead right at the radio. I've never heard of doing this before.   Any
comments on this one?

Doug  VA7DD
----
Your Moderator: Dick Flanagan W6OLD, [email protected] Icom FAQ:
http://www.qsl.net/icom/

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