James Barrett wrote:
Michael Coslo wrote:
There are two grounds for your radio system. There is an RF ground, and
there is a power ground. They aren't the same, and even the term
"ground" is a little nebulous. But it is convention.

The is probably the biggest point of confusion for me. What do you mean
by "RF ground"?

It is confusing, so you're not alone.

RF grounds can be related to Power grounds, but only so far. On say a
ground plane antenna, where you have a vertical center rod connected to
the coax center conductor, and some angled rods connected to the coax
shield, those angled rods are serving as a ground plane. They aren't
connected to actual earth.

This is where a lot of the confusion comes in. The ground plane is more
of a counterpoise, or to look at it as a circuit, a place for the other
part of the current to go.

Now if we look at say a vertical HF antenna of the 1/4 wave variety,
typically this antenna will have "grounding" by way of many radial
lengths of wire that are either buried in the earth at a shallow depth,
or even just stapled to the surface of the earth.

This is "Kind of-sort of" like a power ground, in that it is in the
earth, but its doing something different. It is operating very similarly
to that ground plane. It gives the RF current a place to go.

I didn't go into things like impedence to avoid confusing the issue, but
that would be next in the discussion.



The type of ground I was asking about is the ground
terminal on the back of my radio,not the three prong power plug. There
is the ground terminal on the back of my radio and there is also a
ground terminal on my power supply, even though both have three prong
power plugs. So, are the ground terminals on the back of my radio and
power supply called RF ground, or are the called Power ground?

The ground terminals on your equipment are part of the power ground,
that you would attach to the pipe in the yard. Explanation of that
below. Any RF ground would be considered to be on the shield of the coax
connectors.

Because I
thought that the power ground was the three prong plug.

Yes, generally. One of the reasons that we put in a separate ground rod
from house ground for a power ground is that there can be currents on it
after going around the house. It's still mostly neutral, but with
hundreds of feet of that green wire running around the house, you can
still get some currents.


Some people can "get away with" not having a station power ground.
Kinda. I highly recommend one especially for some place to send your
lightning protection.

- 73 de Mike N3LI -