[Elecraft] [Elecraft-K3] Latest on the new home for my K3...

[Jim Brown]

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