In article ,
James Barrett wrote:

The is probably the biggest point of confusion for me. What do you mean
by "RF ground"? 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? Because I
thought that the power ground was the three prong plug.

The intent of the third prong on the power plug is to provide a safe
path from the equipment chassis, back to the power panel (where the
neutral and hot are bonded together). This ensures that if there's a
fault inside the equipment, and a "hot" wire touches the chassis, the
stray current will immediately flow back to the panel via this ground
connection (and likely cause a fuse to blow or a breaker to trip very
quickly). It ensures that you don't end up with a chassis which is
"hot", and isolated from ground... just waiting for somebody to touch
it, accidentally complete a path to ground via their body, and get
themselves mildly dead.

The intent of the ground terminal on the back of the radio is to let
you tie the radio chassis to a good RF ground, so that if any RF
reaches the chassis via conduction (e.g. coming back down the
feedline) it doesn't leave you with a chassis which is RF-hot compared
to grounded objects nearby (this could cause an RF burn if you touch
the chassis, or sneak back into the microphone wiring and cause weird
squawking sounds when you transmit). It's also necessary if you plan
to use a random-wire or similar unbalanced antenna which is designed
to work against the station ground (e.g. radials or counterpoises).

It's normally the practice to bond *all* of the equipment in your
shack together with good (short, heavy) grounding wire or braid...
once again, ensuring that different pieces of equipment have their
chassis at the same (or nearly the same) AC and RF potential. By
doing so, you are in effect bonding together your power/safety ground,
and your station RF ground, creating a single ground system.

Because this in-the-station ground bonding isn't really designed to
handle massive amounts of fault current (e.g. from lighting) and since
it's in an area where you really don't want such fault current to flow
(e.g. your shack), it's still important to bond your station's "RF
ground" rod, and your house's service-panel ground rod, together as
per NEC.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Dave Platt wrote:

The intent of the third prong on the power plug is to provide a safe
path from the equipment chassis, back to the power panel (where the
neutral and hot are bonded together). This ensures that if there's a
fault inside the equipment, and a "hot" wire touches the chassis, the
stray current will immediately flow back to the panel via this ground
connection (and likely cause a fuse to blow or a breaker to trip very
quickly). It ensures that you don't end up with a chassis which is
"hot", and isolated from ground... just waiting for somebody to touch
it, accidentally complete a path to ground via their body, and get
themselves mildly dead.

One of the reasons that Ground fault interrupters are around. If you
have a hundred feet or even more of neutral wire going back to that
panel, you can still get an appreciable current flowing through you
without tripping a breaker. I've had my tookus saved by one of those
GFCI things when a power tool failed in the manner you just described. I
felt the shock for just a fraction of a second, then it tripped.



the chassis, or sneak back into the microphone wiring and cause weird
squawking sounds when you transmit).

Ahh, that happens to me all the time even without RF on the mic! ;^)


- 73 de Mike N3LI -

On Fri, 30 Nov 2007 02:08:18 EST, (Dave Platt)
wrote:

The intent of the third prong on the power plug is to provide a safe
path from the equipment chassis, back to the power panel (where the
neutral and hot are bonded together).

You do mean the neutral and ground, right?
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon

e-mail: k2asp [at] arrl [dot] net

The intent of the third prong on the power plug is to provide a safe
path from the equipment chassis, back to the power panel (where the
neutral and hot are bonded together).

You do mean the neutral and ground, right?

Erp. Yes, indeed! Bonding neutral and hot at the panel would be
spectacular, but rather useless :-)

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!