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

Re: 3 neons

Subject:  Re: 3 neons
  Date:   Thu, 24 Apr 1997 16:45:02 -0400 (EDT)
  From:   Esondrmn-at-aol-dot-com
    To:   tesla-at-pupman-dot-com


In a message dated 97-04-24 04:14:50 EDT, you write:

<<    This is what I'm planning:
     I'm using two 0.05 caps in an equidrive set up. With this type of 
 setup I am rather worried about strikes from the secondary to my
 primary. If this ever occurs, then I'm going to more than likely end up
 with one or two dead CP's. So I'm trying to make my primary as
 unatractive to my secondary as possible by using a strike rail, with
 a good rf ground, set 
 about two inches up and out from my flat primary. Also, I'm planning
 on covering my primary with a sheet of plexiglass. I'm hoping this will
 be enough.
 
     To protect my transformers, I'm setting my gap to no more than .25 
 inch and wont turn the variac up to more than 80% I'm looking for some
 good ferrite cores to wrap two chokes upon and will also use a safety
 gap. I may also just use neon transformer cores to wrap my chokes upon, 
 But am uncertain if these cores my run into saturation problems.
 
     Primary is made of 12 turns 3/8 inch ref. copper tubing spaced 0.25 
 inch apart in a flat spiral.
     Secondary is 6.25 X 24 inch pvc wrapped with 22 gauge 37 turns per
 inch and coated with pollyurethane inside and out.
     Toroid is 7 X 24 inch aluminum dryer duct with two layers of duct
 tape and a top layer of aluminum tape with two circular pieces of roof
 flashing for the top and bottom.
 
     Criticisim is eagerly awaited especially concerning primary ind.
 protection and transformer protection.
 
 thanks,
      Bert S.
  >>
Bert,

Sounds like a good project.  It should perform well.  Definitlely use a
center grounded safety gap mounted near the neons.  On my small coil, I
am
using two inductors made from about 3 inch ferrites wound with as much
#24
pvc insulated wire as I could get on them.  These are in series with
each
high voltage lead between the safety gap and the main spark gap, and
also
have a 3,000 ohm 25 watt resister in series with each leg.  Haven't lost
any
neons yet with this set-up.

The strike rail is definitely a good idea.  You may need to put a nail
or
other sharp object on the toroid to direct the strikes upwards.  You may
also
try what I just discovered - using two toroids, the larger on the
bottom.  On
top of this use a metal cylinder made of aluminum roof flashing say 8"
high
then another toroid on top of that.  The second toroid needs to be at
least a
couple of inches smaller than the bottom one.  This will direct almost
all
sparks to leave from the upper toroid, and will go out or up.

Strikes to the strike rail should not bother the neons, provided the
strike
rail has a good connection to your main RF ground.

Ed Sonderman