On Mon, 30 Jul 2007 12:08:33 -0700, wrote:

On Jul 30, 10:04 am, Danny Richardson wrote:


Not true. Feeding an antenna with coax does not remove the need for a
station ground and here's why:

http://k6mhe.com/sub/BlancedFeedLine.pdf

Danny,K6MHE

The coax has nothing to do with it. Whether or not the antenna is
complete will be a much more deciding factor.
But still, I see nothing in the pdf that would imply a ground
is needed for feeding such an antenna, coax fed or not.
Only decoupling of the feedline is needed. Not a shack ground.
Why would one "need" a station ground in that case, assuming
the feedline is decoupled?
How would adding a station ground improve operation of a "complete"
antenna that was not well decoupled?
Myself, I would consider that a "bandaid" approach to the common
mode problem. A ground can hide problems in some cases, but
it never actually fixes anything. Common mode problems should
never be "cured" by station "RF" grounding.
MK



May things you say are correct, but remember that a balun/choke does
not totally choke off (eliminate) common mode current on the
transmission line (particularly a multi-band antenna system) and a
good station ground can provide additional reduction RFI problems.

For example here at my station where I have a half way decent single
point RF grounding system. If I remove just my ground connection to my
tuner - leaving everything else intact - and turn on my old CRT
computer monitor I have over an S9 noise level. Reconnect the ground
connection to the tuner the noise drops to less than S2. [BTW: I found
that out quite by accident when I rearranged my station.]

Station grounds can beneficial for several reasons.

Danny, K6MHE