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Re: Neon pricing

In a message dated 96-02-21 12:49:53 EST, tesla-at-grendel.objinc-dot-com writes:

>Everyone,
>
>
>        I hooked up one side of the 15Kv 60ma "bad" unit in place of my Xeon
>starter xformer and immediatly had 1' sparks break out from my 28" by 4"
>torroid! My little starter xformer would never do that.
>
>
>        Specs:
>
>        primary:        15.5 turns inverted cone 1/4" copper tubing.
>                        11.75" inside diameter
>                        41"    outside diameter
>                        30 degreee rise.
>                        124 uH measured inductance.
>
>        cap:            0.0137 uF measured 
>                        10" by 96" rolled flashing and 0.060" polyethylene
>                        in transformer oil.
>                        I'm a little woried about blowing this with 15Kv.
>
>        Fo              122KHz
>
>        spark gap:      three 3/8" by 1 1/2" carriage bolts. I will build an
>                        RQ cylinder gap today!
>
>
>        Secondary:      two polyethylene trash cans glued together 7.5" to
>                        8" to 7.5" 20 5/8" long.
>                        wound with 22 A.W.G. magnet wire. 2 coats of water
>                        based polyurethane over it. Oops!
>
>                        33.4 mH measured inductance.
>                        238Khz self resonant frequency => 13.5pF self
>                        capacitance
>                        133Khz resonant with 28" by 4" torroid => 30pF
>                        torroid capacitance. 
>                                                note: the torroid was
>                               measured on the coil which was sitting
>                               on the floor of the garage.
>
>
>Any thoughts? comments? At this level of Power, 7.5Kv 60ma, what size sparks
>are reasonable?
>
>
>                                        jim
>
> ps.
>        I mispelled tesla and this message bounced. Since then, I've built
>RQ's gap and got a (measured, straight line distance) spark of 20".
>
>                        I can't say more power anymore. I have to say MORE
>ROOM!
>
>                                        jim

Jim,

Sounds like a good system, especially with the new gaps.  I would say you are
right about on track with 20" discharges at 450 watts input.  This is 271
watts per foot of spark.  When I was still using neons, I got 34" with 12kv
60 ma in which is 254 watts per foot of spark.

You are right to worry about blowing your cap with 15kv.  I am convinced
these .062 poly rolled caps can only be used safely up to 9 or 10 kv.  I was
using one capacitor, 12 kv 120ma and getting 50" discharges for about one
minute and blew the capacitor.  Then I ordered a commercial cap and tried to
hold the voltage down on the last cap until the commercial cap arrived and
blew it also at about 10 or 12kv.

You mentioned you primary was sitting on the garage floor.  You should sit it
up on something about two feet above the cement.

Ed Sonderman