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Re: Nathan's Saga Update...

Tesla List wrote:
> 
> Original Poster: "Nathan Ball" <nateburg-at-hotmail-dot-com>
> 
> Terry, all,
> 
> I don't have any variacs running the coil.

This should be your very next coiling purchase!

> 
> On the note of the wierd corona coming off the wires that aren't connected
> to anything, I had some similar strange problems before.
> 
> When I first added a grounded strike rail around the primary, I used the
> same quarter inch refrigeration tubing to build it as the primary is
> constructed of.  I made posts of the tubing and used a ton of hot glue to
> attach them to the vertical legs of the triangles supporting the primary.
> 
> I then used foil tape to attach the strike rail to the vertical posts, so
> there was reasonable continuity to between the posts and the rail.  For some
> dumb reason I attached the wire from the ground to one of the posts, instead
> of to the rail.  There was still good continuity... but I should have put it
> on the rail itself to insure good connection.
> 
> When I turned the coil on, loud yellow sparks began emitting from where the
> two ends of the rail itself were taped together. I didn't consider it
> necessary to solder the rail together since there would be 0 ohms around the
> other the rail anyway.

BINGO! If your strikerail is arcing end-to-end, the ends are too close
together, and substantial energy is going into the "shorted turn" of
your strikerail instead of into output streamers! Your strikerail should
NOT make a complete turn. Slip the loose ends into a piece of 1/4" ID
polyethylene or vinyl tubing, leaving _at least_ a 3/4" gap. 

> 
> The only explanation I have for that is that the potential was so
> drastically different from each side of the ring-strike rail that it had to
> spark?  

YES! the ends of the strikrail may actually have several thousand volts
of RF induced from the primary due to simple transformer action. 

But it wasn't even a blue arc, it was yellow sparks that looked like
> they were fireworks.  I had it taped together with foil tape.

You'll get heavy short-circuit current in a single turn - it could esily
be many hundreads of amps even for a small coil - certainly enough to
melt copper or aluminum under arcing conditions. "Fireworks" are not
surprising under these conditions... :^)

> 
> >From the motor of my rotary gap, I have the wires from the motor going to
> two L brackets attached to the 2x4 frame of the coil.  the L brackets are
> screwed into two pieces of pine that are glued to the 2x4 to try to prevent
> conductance between them; it seems to have worked.
> 
> THe wires of the motor are alligator clipped to these, and there is the
> extension cord that is alligator clipped to the L brackets as well, so I can
> quickly take the coil apart.  For 120V, low amperage draw from the motor, I
> think these connections are adequate to run the motor.
> 
> The extension cord then comes down and is zip tied every foot to another
> extension cord which runs the 120V line from the outlet to the NST on the
> frame of the coil.
> 
> Both cords terminate at the other end with plugs, but the motor cord has a
> speed control right before the plug for the rotary gap.
> 
> When I have been running the coil, I have it hooked up so that the RQ gap is
> in series with the rotary to try to enhance quenching, and so when I run the
> gap on "static gap only" mode, the rotary gap is simply lined up with its
> electrodes to act as two more gaps in series.

I'd recommend connecting the static gap in _parallel_ with your rotary,
since the electrodes on the rotary won't quench well (and may overheat)
if the rotary is not running - no high velocity air cooling. You might
even melt the plastic rotary around the electrodes. Move your rotary
into a position so that it does NOT arc. You should be able to increase
the number of gaps on the RQ gap, and should also see better quenching
and coil performance. Use this setup until you have your coil operating
correctly. DO NOT attempt to use the rotary until the coil is in tune,
and operating with NO abnormal arcs, corona, or other "wierd" behavior,
or you'll run the risk of damaging parts of your system.

> 
> The rotary's rotor is a 3/8" by 6 1/2" dia lexan plate, with the electrodes
> on a 6" diameter.  The electrodes are all connected electrically with wire
> on the back, and so I have my fixed electrodes across from one another, 6"
> apart, so they will fire in one side, out the other when the electrodes come
> into proximity.
> 
> The electrodes have no connection whatsoever to the input wires to the
> motor.  Those are the wires that connect to the L brackets, to which is
> connected the extension cord, which is emitting very visible corona when I
> run the coil.
> 
> It also melted a little bit of the carpet.
> 
> My dad doesn't want me to run the coil (the way I have been, using the
> "static" rotary in series with my RQ gap) until I figure out what's
> happening with the corona discharge from the end of the cords.

See my other post. Your power cord is acting as an antenna. If you can't
roll it up, then connect both prongs of the plug to your RF ground. 

> 
> Oops! I failed to mention, the cord that emits the corona is not plugged
> into anything because I havn't been using the motor which it runs.  Only the
> cord zip tied to it is plugged in, because it runs the NST.
> 
> Sorry this is such a long letter, but I want to be as specific as possible
> to try to find out what's going on with my "phantom corona".
> 
> Really, though, any of you ever perform an exorcism on a possessed coil? ;-)
> 
> thanks,
> Nathan
> ______________________________________________________
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Make the above changes, plus tuning the system per my other post. This,
combined with the new MMC cap, should do the trick! Safe coilin' to you,
Nathan!

-- Bert --