[TenTec] grounding

[Gary Hoffman]

Unless there is a problem elsewhere in the system, your earth ground should
not be carrying "significant RF currents".  If it were, then your energy
intended for transmission would be heading to ground, via a very short (we
hope) wire.  Now I must agree that there are many errors that can be made in
a shack that could result in this undesired situation.  Balance is much to
be sought after.

However, no system will be perfect.  There will be small, residual RF
currents trying to find ground no matter how well designed the shack is.
Conducting these stray currents to ground via a proper RF ground, is, in my
view, the best thing that can be done with them.

Then too, there is lightning.  Not likely to be balanced vs your setup, but
it IS RF.  You want that to go to ground also.  And not through your
equipment either !  Another ground design point that must be addressed.

73 de Gary, AA2IZ


----- Original Message ----- 
From: "Ken Brown" <ken.d.brown at hawaiiantel.net>
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Sent: Tuesday, January 09, 2007 11:11 PM
Subject: Re: [TenTec] grounding


>
> > Doesn't a good earth ground help remove stray RF from the shack? along
with
> > ferrtie cores etc...
> >
> No. Any conductor carrying RF currents, not having another in close
> proximity with equal and opposing RF currents, as in a transmission
> line, produces RF radiation. A lead to a "good earth ground" carrying
> significant RF current, will produce significant RF radiation. The key
> to minimizing RF in the shack is to have all your transmission lines
> working as transmission lines should, with equal and opposite RF
> currents flowing in the two conductors (whether it is the coax center
> conductor and shield, or the two wires in parallel wire line) so that
> they are transmission lines and not antennas. There are various details
> that need to be attended to to accomplish this. With good connectors, a
> properly working transmitter, properly built cables and either a
> non-radiating load (not very useful for communications, yet an essential
> piece of equipment in every shack), or an antenna far enough away from
> the shack and properly fed so that it does not induce unequal RF
> currents into the two conductors of the feedline, there is no reason
> that there would be RF in the shack. It is only when one or more of
> those conditions is not met that there is a problem. Adding another path
> for RF currents to flow, such as a ground wire, is probably just as
> likely to make the problem worse as it is to make it better.
>
> DE N6KB
>
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