Proper Station Grounding and Avoiding Ground Loops

[outlaw0814]

wow -- i thought after playing with radios and working with cars and trucks all my life i knew everthing about grounding things-- I was wrong thanks for the new perspective--- i just learned something new and im over 40 -- who says ya cant teach an old dog new tricks

[710]

In a base station setup, all of your equipment is "grounded" together via the coax shield. Adding additional wires between each piece of equipment will create a ground loop, as the shield and additional wires will be at a different ground potential. A single short wire from your radio to a ground rod will suffice. Some say,and I happen to agree, that if you need a rf ground wire and rod, something is not right with your antenna system. The antenna system should be balanced to the point that the radiator and the radials do the "work". Not using radials at the base of the radiator ? There's your problem.

[Slim Pickins]

Some of this stuff is a little confusing and some not so much, I better do a little more reading on the links.

[icemanrrc]

In a base station setup, all of your equipment is "grounded" together via the coax shield. Adding additional wires between each piece of equipment will create a ground loop, as the shield and additional wires will be at a different ground potential. A single short wire from your radio to a ground rod will suffice. Some say,and I happen to agree, that if you need a rf ground wire and rod, something is not right with your antenna system. The antenna system should be balanced to the point that the radiator and the radials do the "work". Not using radials at the base of the radiator ? There's your problem.

I had posted once that my base setup was bleeding all over tvs, computer speakers, etc, etc. I was told that I needed to ground everything, radio, amp, power supply, etc. Now, you are saying that I shouldnt?

[Foxhunter]

In a base station setup, all of your equipment is "grounded" together via the coax shield. Adding additional wires between each piece of equipment will create a ground loop, as the shield and additional wires will be at a different ground potential. A single short wire from your radio to a ground rod will suffice. Some say,and I happen to agree, that if you need a rf ground wire and rod, something is not right with your antenna system. The antenna system should be balanced to the point that the radiator and the radials do the "work". Not using radials at the base of the radiator ? There's your problem.

Let me first comment briefly on the post above, then add a few additional thoughts to end the post. Your really DON'T want to intentionally add extra "additional wires between each piece of equipment", because the "daisy-chain method" of series-linking station pieces together, and finally terminating at the end into a ground point, is to be avoided. And like I already tried to demonstrate in text and via several diagrams, unfortunately the individual components are already series-connected via the coax shield to begin with.


These separate station accessories are all (hopefully) DC power grounded via their power cabling. To take it a step further, the individual pieces often need to be "RF grounded" for stray RF radio signals, which often cause many problems to operators working their equipment in the shack. For RF grounding, the various station pieces in-effect need "small antennas" attached to them, which (in a nutshell) drain away any residual stray signals to ground. The small RF grounds, kept to a very short length, act as a very poor antenna and don't radiate the signals (which is what we want!) but again absorb them and drain them off and away to ground.

The idea of having and using antenna ground "radials", either elevated or buried, is a related antenna & tower/mast installation issue and other aspect from "safety grounding" and "RF grounding" in the shack, although it will also be another important component of overall station grounding. "Ground radials" and/or an elevated ground plane have a direct bearing on your launching the ground-wave component of your signal and the radiation take-off angle of your signal. A good "key word" or "key phrase" to look up and research for station grounding is-----"SPG" or "Single Point Grounding".

The 3 ideas and methods of DC Grounding, RF Grounding, and Safety Grounding are sound principles, and there are many official webpages via the ARRL and other RACES etc organizations on the separate facets of station grounding, all three aspects of it. Who knows in the end ? Some operators claim and write NOT to need any grounding at all.




All I can say in the end is:
Use what you think is best, buy your own books, do your own homework and spend many hours reading up on the subject---and ultimately come to your own conclusions and make your own decisions. As best you can. If anything, the thread topic might have led to some questioning of "what ground is" and caused viewers to further inquire and read about radio station single point grounding, and the nature of "a ground loop".

Also purchase a copy of the NEC National Electrical Code and become VERY familiar with the wiring requirements for your home station, not only are your family's lives possibly riding on it, but also your homeowner's insurance and fire insurance coverage---requiring a proper to-code installation---all depends on it too.


Foxhunter 351 NJ

[Mikey B]

As always Foxhunter, another great and very informative thread. Nice job!
(and I do realize it is over a year old)

73

[710]

I never suggested not using a station ground. I merely stated I agreed with the notion that if your antenna system was working proper, one was not required. If you are using an end fed antenna like the i-max, with out a sufficient ground plane/counterpoise directly below the base, the antenna will attempt to use the coax/mast as the "missing half" of the antenna. This will induce large amounts of rf into your shack. Grounding these currents through the use of a ground wire and rod only mask the real problem. I still maintain the use of additional wires between station equipment will create a ground loop with one possible exception. That being, wires exactly the length of the individual coax pieces. What would be the point in that as you already have a wire (coax shield) that very length to begin with. Try it both ways and observe the difference if any. Trial and error is the only way you will know what you are doing.