To: <rfi@contesting.com>
: Date: Fri, 29 Sep 2000 09:37:16 -0400
: From: David Jordan <wa3gin@erols.com>
: Subject: [RFI] Grounding the Operating Position
:
: Hi Folks,
:
: Getting ready to set-up a ground buss behind all the equipment on the
: operating table. Running a six ft piece of 1/2 inch copper pipe which
: is connected to the ufer ground system.
:
: Want to ask whether 1/2 inch flat silver tinned braid strap is OK to use
: to interconnect the equipment to the copper pipe. I expect the jumpers
: will be from one to two feet long.
:
: I vaguely remember reading that braid was not preferred when trying to
: reduce unwanted RF currents. If my memory serves me correctly it was
: stated that a piece of #16 guage wire was better than using 1/2 inch
: braid.
:
: thanks,
: dave
: WA3GIN
:
Actually I have had my best results without in inside ground at all.
I use Double shielded coax jumpers for all equipment RF
interconnections and physically mount and ground splitters, filters
and Polyphasers at the entrance.
Copper or bronze strapping is preferred, but heavy gauge solid
copper wire or tubing is a lot better than braid, and is easier to
come by. Braid is good for heavy flexible DC connections, or
60 cycle grounding, but can cause RFI as it ages. Silver tinning
the braid goes a long way in combating RF noise, but burns out
easier from lightning.
It may help to ground individual pieces together, or it might not.
The wiring on the way to the "real" ground can act as an antenna,
actually spraying RF around in the shack. Also I am leery of
bringing lightning and high static potentials to my op position.
Jim, ac6tk
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