On 4/22/2020 1:51 PM, Dave Cole wrote:
I am trying to reduce the potential for ground loops, so I will not be
using the patch panel as a ground connection point, it will just look
like long coax runs to the equipment.
Ain't no such thing as a "ground loop," except to the extent that it
could couple a magnetic field. In practice, that only happens when
there's an error in mains power wiring, or when there's leakage flux
from a big power transformer in close proximity. Indeed, with proper
bonding for lightning protection and hum/buzz/RFI control, there SHOULD
be loops due to multiple bonding paths. That's addressed in this slide
deck for talks I've done at Visalia, Pacificon, and to multiple ham
clubs, and most of it was incorporated in Ward Silver's ARRL book on the
topic, on which we collaborated.
http://k9yc.com/GroundingAndAudio.pdf
I will be installing an entrance panel, and an additional ground rod
later this summer.
The entrance panel will be connected via #6 to a set of three 8 foot
ground rods, one at the electrical service, one at my shack, just
outside the house, 15 feet away from the service ground, and a third, 15
feet further down the house, all connected with #6 as well.
All incoming coax will be fed in via the entrance panel. The entrance
panel is a NEMA4 weatherproof box, 3 by 2, with a 1/4 inch copper sheet
bolted to the raised supports in the rear of the box.
The copper plate inside the entrance panel is where the station outside
ground system connects, and where the stations inside ground system
connects via a Polyphasor on each coax cable, and a #8 copper wire.
On the rear of the desk will be a CM Choke I constructed-- RG-400, on
two FT-240/31 cores.
At the antenna, is coax, feeding the Entrance panel. I am conflicted on
grounding the base of the antenna, and possibly adding another set of
Polyphasors there... More reading is needed on this...
The aforementioned link, and Ward's book. BTW -- all the connectors on
that beautiful new panel SHOULD be bonded to the panel, and the panel
should be bonded to your station ground bus. Elecraft's earliest VHF
transverters were built with feedthrough BNCs that were insulated from
the shielding enclosure, and the two I bought used are unstable as a
result.
73, Jim K9YC
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