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Series resistor

Subject:  Series resistor
  Date:   Fri, 25 Apr 1997 21:12:43 -0700
  From:   "DR.RESONANCE" <DR.RESONANCE-at-next-wave-dot-net>
    To:   "Tesla List" <tesla-at-pupman-dot-com>


Hi Ed:

Does the 25 W  3 K resistor seem to heat up very much during operation? 
Enough to pose any fire hazard?

I've used some 100 W. 500 Ohm resistors also wound like a parasitic
choke
with about 40 turns of #16 AWG.

DR.RESONANCE-at-next-wave-dot-net


----------
> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-poodle.pupman-dot-com
> Subject: Re: 3 neons
> Date: Thursday,April 24,1997 10:19 PM
> 
> 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