WB6BYU,
I'm actually an electrical engineer and did already read the ARRL book several years ago. My main reason for posing my questions here is to hear people's thoughts on the topic ... and I've forgotten most of what the ARRL book said, so I sent for it again. We're building a house and lots of my stuff is in storage until that's complete.
The house has a dedicated 'radio room' (and office) and I just spoke with my electrician ... he's going to run a heavy gauge ground from the electrical panel's earth ground over to a ground bus in a shallow box, under the (to be) desk area, for radio equipment grounding. I'll get a 1-1/2 inch diameter 2-3 ft length of copper pipe etc... devices ground to the pipe, pipe grounded to the ground bus, ground wires same length and connected symmetrically about the wire to the ground bus etc.
The purpose of the grounding described above is to be the frame ground for all shack equipment. On DC devices, the black (-) terminal, is connected to the frame ground, although it's also called the circuit ground. Same in the house electrical panel ... the black, and the white current-carrying neutral, are connected to the house as well.
RF grounding is complex because any path to the ground (the DC ground above) is going to see an input impedance that has resistive, inductive reactance, and capacitive reactance. The reactive impedances are a function of frequency ... to design an effective RF ground, you have to pick your frequency to design around. Considering static noise, electrical noise, and the broad range of frequencies in our band plan, a single RF ground is impossible if you want it to work well across the board. I'm convinced that the best ground system is a well-done DC ground as described plus RF chokes on the coax just outside the shack is probably the best you can do ... dampen/absorb the common mode RF, don't ground it (you can't really). Comments welcome ... I'm new at the amateur radio thing ... been licensed for awhile, but just now live on property that lets me do what I want without petty neighbors and petty tyrants telling me what to do (HOA/CC&Rs people taking money from you so they can tell you what you can and cannot do on YOUR OWN property).
I'd have to dig out the equipment to see, but I also have an ICOM IC-7100, MFJ power supply, and LDG tuner in a box somewhere ... one or two of those devices do not even HAVE a ground screw or lug on them ... impossible, without modification, to ground all of those devices at the same time. I suspect (without looking it up) that it was the radio and tuner that had no ground screw. The tuner shouldn't need it, the radio's frame ground is likely connected to the black terminal for input power, and therefore depends on the power supply's black terminal/frame ground/ground screw for ground ... and the power supply frame ground also connected to the safety ground in the 3-prong plug for wall power. That's daisy chaining, albeit short, and not a superior answer.
I still need to look into lightning protection and grounding at the antenna (I'm not convinced the shield should be, but a ground rod for lightning protection is a good idea)
Anyway ... off to work. I'll try to get some KE0OG vids in this weekend ....
K4JUL
Author
Topic: Wire gauge? Grounding? (Read 287 times)