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Re: Grounding. Oh joy.

> Original Poster: "Yuri Markov" <wmondale-at-hotmail-dot-com>
>
> 1. I have heard that it can be a good idea to epoxy a flat piece of copper
> to the base of a secondary to serve as a ground terminal. Would a piece of
> aluminum tape work also?

Yuri, I feel that the absolute best way to terminate the ground end of a
secondary is the copper patch/soldered nut approach.  Take about a 1" x 2"
rectangle of copper and round the corners.  Lay this on top of the base of the
secondary and scribe a mark around the outline.  Now take a dremel and
route out
the area under the patch so that it will lay down almost flush with the PVC.
Don't go all the way through the PVC, just the thickness of the patch.  Now
take
your patch and solder a large nut to it (I used a 1/4 nut and heated it with a
torch).  Now solder the secondary wire to the patch.  Then you just clean
everything up and epoxy the patch to the PVC (or other secondary form).
You can
skip the flush mounting part if you like, it's not mandatory, it just makes it
pretty.  I got my sheet of copper from an art store.  I also see them at hobby
stores.

> 2. I have heard that I can use something vaguely like chicken wire called RF
> Grounding Strap to ground the secondary. Where do I get this? THe local
> hardware store? Home Depot? Or the ends of the Earth?

Just use some copper strap or 8 ga wire with ring terminal attached to it.
Copper strapping is the undisputed champ when it comes to routing high freq
current around.  Braid may not be the best solution due to its impedance at
high
frequencies with high currents.

> 3. I have heard that I should not ground the secondary to a water pipe. Why?
> I'd like to know, because I don't feel like diging a six-foot-hole when
> there is an iron well in the backyard that goes a whole lot deeper than six
> feet.

I think the water pipe is frowned upon because other things in your house may
also use the water pipe as a ground.  The RF may travel up the water pipe and
get into household electronics.  Someone correct me if I am wrong...

Just drive an 6-8 ft section of 1" copper water pipe in the dirt and use it.
The water pipe is a few bucks cheaper than a copper coated steel ground
rod.  If
you coil a lot, why not just drop the $20 and install a real 8 ft ground rod?

An even better idea is to just use the well!  (Verify that the house ground is
not tied to the well)

> 4. I have heard of coils "failing" when they are not properly grounded. Is
> this failing as in "not doing anything," or as in "blowing up beyond all
> hope of repair and forcing me to wind another three pounds of magnet wire on
> another ten dollar PVC pipe?"

I believe that they are referring to arcs between the primary and bottom of the
secondary.  This is common with a poor ground.  It  isn't good for the wire on
the secondary...

Good luck,
--
Ross Overstreet
Huntington Beach, CA
ICQ 20762411