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Re: Secondary Spark Capacitance (was How to rise the secondary?) (fwd)



---------- Forwarded message ----------
Date: Tue, 21 Jul 1998 05:10:16 +0000
From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Secondary Spark Capacitance (was How to rise the   secondary?)


  Richard, All -

  Thank you for again explaining this test. I somehow missed your previous
posting. The secondary spark capacitance would be difficult to measure
because this change in the secondary capacitance cannot be measured
directly. If I understand your test correctly you measured the change in
secondary capacitance indirectly by measuring the change in primary
inductance. This sounds possible but there are problems.

  One of the problems is in measuring the change in the primary inductance
that is directly related to only the capacitance of the sec spark. The
electric field around the coil and the ion cloud could also be involved.
Another problem is that there are two different types of tests being used,
low voltage with a signal gen and high voltage with power on. The tuning
errors of measurement would be hard to eliminate. These errors could be what
you are finding in the tests.

 A problem also arises in the fact that the spark is on for such a small
period of the break cycle. For example, the break peroid for 120 BPS is 8333
us. The time the spark is on is only about 1/3000 of this time. The spark
capacitance would not have much effect. The ion cloud and the electric field
capacitance, if any, would have more effect.

  Hopefully, you and other coilrers in the future will make more tests and
confirm what effect the spark capacitance has on the TC operation. To my
knowledge you are the only one who has researched this interesting
possibility. Are there other coilers who have performed these tests?

  John Couture    

----------------------------------------------

At 09:52 PM 7/19/98 -0600, you wrote:
>
>
>---------- Forwarded message ----------
>Date: Sun, 19 Jul 1998 16:58:27 -0400
>From: Richard Hull <rhull-at-richmond.infi-dot-net>
>To: Tesla List <tesla-at-pupman-dot-com>
>Subject: Re: How to rise the secondary? (fwd)
>
>
>
>Tesla List wrote:
>
>> ---------- Forwarded message ----------
>> Date: Sat, 18 Jul 1998 06:03:08 +0000
>> From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
>> To: Tesla List <tesla-at-pupman-dot-com>
>> Subject: Re: How to rise the secondary? (fwd)
>>
>>   Richard -
>>
>>   How did you measure the frequency with and without streamers. Do you have
>> any data on frequencies and streamer capacitances?
>>
>>   John Couture
>>
>> ---------------------------------------------------
>
>This was explained in a post 2 days ago by me on this list.
>
>1. measure the no power all up load resonance with sig gen and led.
>2.  Tune for maximum spark.  measure new primary inductive tune point.  Back
>figure to new resonant freq.  This is sorta',... kinda' close to something like
>the center freq of the running dynamic tune of the system.
>
>Richard Hull, TCBOR
>
>