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Ground question


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From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Sunday, March 15, 1998 4:35 PM
To:  Tesla List
Subject:  Re: Ground question

Hi Alan,

> From:  ajones-at-nwga-dot-com [SMTP:ajones-at-nwga-dot-com]
> Sent:  Sunday, March 15, 1998 7:26 AM
> To:  tesla-at-pupman-dot-com
> Subject:  Ground question
> 
> Coming out of 'Lurk Mode'....
> 
> I've been pounding some ground rods to replace the wimpy ground I had
> been using and have a question about the hookup. There is a cable
> running to my satellite dish that will cross the path from the ground
> rods to the coil. Will there be a problem with this? I could
> disconnect the cables at both ends when running a coil if necessary
> but there is a hill to climb to get to the dish. I'm not exactly old
> and worn out yet, but would prefer not to do this.
> 
> What's in the wire going to ground? Is there voltage or current flow?
> I've always wondered about this and have been waiting years for
> someone else to ask. Since I don't remember if anyone has, I guess I
> have to put on the dunce cap today and grin-n-bear it  :-)

Current, and plenty of it. Voltage wrt to ground at any point is 
determined by the impedance of the ground+cable back to that point 
and the current flowing in the cable. If ground resistance is 
insignificant and operating frequncy is low (reduces cable reactance) 
voltages will be reasonably low.

> What about running the ground wire overhead and then dropping straight
> down to the ground rods?

Bad idea. You have in effect a toploaded aerial with a high "antenna" 
current. The resonator behaves as the topload. The longer the wire is, 
the better it radiates.

 I remember someone saying two or three years
> ago that flashing or strap could be duct taped to the floor and run
> out this way. That is the reason for my question about what is
> actually in the ground wire. If this would be safe then my way would
> seem to be also. I have no problem with taping flashing or ground wire
> to the floor, but I still have to get it across the sat cable and
> going overhead seems to be the only way, short of going all the way
> around the house. And the ground wire is certainly stiff enough to
> stand up for the few feet to the ground rods.
> 
> And would the wire radiate out in the open like this? I know better
> than to hook a wire to the top of a coil since that would be an
> antenna, but what about the ground?

Just as bad.

Malcolm