Grounding your radio

 

It seems that everyone thinks a radio should always be grounded to work or for best performance. That is actually not true. 

Grounding is a complicated issue. Indiscriminate grounds for no real reason tend to hurt more than they help! Grounding a radio to an isolated ground rod is definitely not a wise thing to do regardless of who says it is. 

Old radio manuals always showed the radio connected to a ground rod. Nobody asked why. Yes, there was a reason back in the early 20th century when most radio antennas needed the ground as a return path for antenna current. For example a crystal radio when connected to a random end fed wire would magically come to life when the G terminal was connected to a ground rod! Even today end fed wires will not work without some return path. That return path could be an earth ground rod connection. Doing so needs to be done right or it’s a catastrophe waiting to happen! Some new radio manuals still show a connection to ground. I can only think that the reason is the people writing the manuals have no understanding of grounding and just keep repeating the error. The return path could also be a form of counterpoise. The return path could also be accidental and the antenna may still work to a certain degree and this makes the operator think a counterpoise is not necessary. He just does not know where the path is for the return current. I guarantee the antenna will not radiate unless there is some return path either intentionally provided by design or accidental provided by luck! 

A ground at the radio is not necessary when using a dipole or most any other antenna that is properly designed. I have never seen it help performance. In my opinion it is rarely necessary.

Grounding has some purposes. There is grounding for safety. There is grounding for lightning. Grounding should be for a specific purpose. I can’t stress enough that an isolated ground rod should never be used as a radio station ground. It must be properly connected to the electric service ground rod! That’s not just a code requirement without a good technical reason. Do not violate it. You can be lucky and get away with it for years but it’s a deadly gamble. You can not stop lightning damage but you can prevent some of the effects from a nearby lightning strike. 

My only ground connections are through the green and white wires in the power cable that goes back to my power panel and to the service entrance ground. This info comes from my 30 plus years as both a power engineer and a radio/ electronics engineer as well as a long time Ham.

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