[Prev][Next][Index][Thread]

R-C-R restrictor, uh... filter



(Alternate subject: Remover your RCR filter and I'm calling the police!)

I performed the most beneficial experiment in the history of my coil
tonight.

I have been using the "Fritz" R-C-R filter between my spark gap and NST bank
since I began coiling about a year ago.  I am running a 6"x25" secondary, RQ
gap (.180-.210"), and currently .045uF of capacitance and a NST bank that
measures 12KV open and 150ma shorted.

I placed 2 toroids on my coil, retuned, and began testing for maximum arc
length.  I managed to just barely squeeze out 48 inches to the ground rod.
I never got a good power arc, just little spindly, barely visible arcs (I
was also fighting a mild crosswind).

Now for the scary part - Risking a hundred plus pounds of NSTs, I removed
the RCR filter and jumpered the wires that used to route through the filter.
I stepped back and hit the dead man switch on the controller.  WOW!  A
white-hot arc the diameter of a pencil attached itself between my corona
point and the top of the ground rod!  It arched up from the heat and
immediately reattached to the rod.  The sound and intensity of the arc made
me take a step back - my coil was acting like an entirely different machine!
It looked much more like a PT powered coil than NST coil.

I managed to get a solid 66" arc point-to-point with the new configuration.
Not only did I get another foot and a half of arc, the arc is entirely
different in it's color, sound, and movement.

The new sound seemed to impress others too - a patrol car came by at 8:37PM
and put the spot light on the coil.  It was a really funny conversation, the
policeman kept asking me what it was and I kept telling him "tesla coil,  t
e s l a  c o i l", then he would just ask again, must have asked 4 times,
hehehe.  Then it was the typical "what's it do and what's it for" game.
Anyway, he was cool and told me that he "didn't think it was a crime, but I
should shut it down for the night".  I reassured him that it was not a
crime, but I could see the "we need some sort of law to stop this unruly
behavior" look on his face.  I digress... back to the filter circuit...

I figure that I was losing (.150^2*5000) = 112.5 watts on each of the
resistors.  That means that I was turning about 450W into heat all in the
name of making life easier on the NSTs.  That 450W sure did make a huge
difference when I put it to good use.  Furthermore, nothing died (yet)!
Hmmm, I still have more caps and more NSTs...

Wishing I still lived back in the woods,
Ross Overstreet
Huntington Beach, CA
http://WWW.GEOCITIES-dot-com/CapeCanaveral/Cockpit/3377/tesla/index.htm