On 4/8/2019 10:55 AM, Richard Solomon wrote:
Theory and practice are sometimes at odds with each other.
NO, they never are. When we think there's a difference, we don't know enough about one or the other.
A single point ground is an excellent idea, in theory. But when the shack is located on the opposite side of the house from the house ground, one does what one can do.
You have a major misunderstanding of what this means. I suggest that you study either N0AX's new ARRL Book on the topic, or the link that W9MDB provided to the slides for my talk on the topic.
http://k9yc.com/GroundingAndAudio.pdf
I have an 8' ground rod, beat into the ground so that only about 10" shows. All shack grounds are tied to it. That includes radios as well as antennas.
That's the major mistake. Everything in your shack should have it's chassis bonded together IN THE SHACK with short, fat copper. I use braid stripped from old coax, which is equivalent to #12 stranded. The computer is bonded via a retaining screw for the DB-connector for the video output. A beefy copper wire should run from that combination of equipment chassis bonds to that rod and all the other grounds in your home -- power, antenna entry, CATV, lightning, cold water -- should be bonded together.
Remember that an earth connection matters ONLY for lightning protection, and a single rod is pretty minimal. I have seven rods for the outbuilding that houses my shack -- one at the power panel on the far side from the shack, two more on the perimeter #8 that runs from there to the shack, and four more on the side of the building outside the shack (and where the coax panel with arrestors enters the shack).
Bonding is also critical for lightning protection, and the bonding inside the shack also minimizes hum, buzz, and RFI.
73, Jim K9YC _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel
