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Re: Filter Choke Design

>>From MALCOLM-at-directorate.wnp.ac.nz Thu Mar  7 16:12 MST 1996
>>Received: from rata.vuw.ac.nz (root-at-rata.vuw.ac.nz [130.195.2.11]) by 
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<tesla-at-grendel.objinc-dot-com>; Thu, 7 Mar 1996 15:41:16 -0700
>From: "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
>To: tesla-at-grendel.objinc-dot-com
>Date:          Fri, 8 Mar 1996 11:42:07 +1200
>Subject:       Re: Filter Choke Design
>
>On the subject of choke core saturation....
>
>> It may be a good thing, for the neon, to operate the core close to
>> saturation. I'm throwing this idea out for comment, please feel free
>> to correct me! The core losses go up, reducing the power to the
>> primary, but by the same token, you don't generate 36Kv to 45Kv across
>> your neon. These were some of the numbers I've generated by spice
>> simulation on my tank circuit. I may, however, be GIGO by using a bad
>> model. Comments? corrections?
>
>Problem is, a saturated core has an induction factor approaching that
>of air, and I think it's agreed that air-core chokes are no good. I
>honestly think that neon trannys don't need chokes, because if you
>look at an equivalent circuit, you see some massive inductance (the
>neon secondary measuring hundreds of Henries) in series with a few
>mH. Additionally, I would think that 5K or so of winding resistance
>would swamp the esr of a small lossy choke. 
>
>Malcolm
>

I have killed at least 2 dozen neon transformers over the past 20 years 
before I started using ferrite chokes.  I've killed only one since I started 
using chokes.  That one was a 15 kv, and my experience is that 15 kv's just 
don't hold up well under Tesla coil stresses anyway.

Chokes work.  Even piddly ones are far, far better than none at all.

Bert