[Elecraft] K2 grounding

[Don Wilhelm]

Paul and all,

There is a big difference between 'not required' and 'should not be done' -
I trust I did not say it should not be done.

It is OK to ground the K2 - I wanted only to point out that it is not
necessary under the conditions stated.  If the tuner is grounded and
connected to the K2 by a coax cable, the enclosure of the K2 will be
grounded to the tuner ground through the coax shield.

If no safety ground is available through the coax, it is prudent to ground
all metal enclosures that any body part could come in contact with.  That is
a safety ground situation, and has nothing to do with RF grounding - those
are two different and separate considerations.

If your K2 power supply negative terminal has a connection back to the AC
utility ground, the chassis of the K2 will be safety grounded without the
need for additional ground connections.  For RF ground connections, these
are better made to the tuner than the K2 chassis.

Connections to a common ground in the shack should be made to a 'single
point ground' rather than to a bus-bar type of ground.  In other words,
connect a wire from the (safety) ground point to a single connection point -
the copper pipe along the back edge of the operating table is not the best
solution - it works for a safety ground just fine, but can pick up noise and
other artifacts by creating ground loops.

There are at least 3 aspects that need to be considered for any grounding
situation in the hamshack - 1) Safety, 2) Noise pickup and ground loops, and
3) RF ground effectiveness.

If I have not been clear on this subject, please try again.

73,
Don W3FPR


> -----Original Message-----
> It sounds like what is being said is not to ground the chassis of
> various rigs. That is, all modern rigs, power supplies, Home wiring
> already have a common three prong plug and that should put everything
> to a common "ground" just by plugging it in. This excludes such
> historical anomalies like the early Astron power supplies that didn't
> have the chassis grounded and are fixed by running a wire from their
> chassis to the DC negative post.
>
> So the rod I have pounded in the ground outside the shack should be
> brought in the shack to connect to the antenna tuner only.  Do I have
> that right?
>
> Because before I was running wire from the ground lugs of all the
> rigs, and computer chassis to a single copper pipe behind the gear
> and that pipe was then connected to the outside ground rod by another
> wire.
>
> I think I'm mixing old and new technology. Maybe a lot of this
> grounding lore came from yesteryear when three wire power cables and
> gear design was not the norm.
>
> If I wanted to check if I should attach some gear to that outside
> ground, would I put a meter between the outside ground wire and the
> rig chassis to see if I could measure anything. If so, what would I
> be looking for? Or put the meter between the chassis of two pieces of
> gear. If they all use three prong plugs, wouldn't they all be common?
>
> Thank you and 73,
> Paul, K7NHB
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