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Re: raise the secondary.... (fwd)
---------- Forwarded message ----------
Date: Tue, 14 Jul 1998 03:56:48 +0000
From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: raise the secondary.... (fwd)
Terry -
Thank you for the information regarding the stremer capcitance. It appears
that if there is any capacitance it is small enough to ignore in calculations.
John Couture
--------------------------------------------------------------
At 09:57 PM 7/12/98 -0600, you wrote:
>
>
>---------- Forwarded message ----------
>Date: Sun, 12 Jul 1998 16:18:34 -0600
>From: terryf-at-verinet-dot-com
>To: tesla-at-pupman-dot-com
>Subject: raise the secondary....
>
>Hi John,
>
>I can measure the frequency of each ringdown cycle to about 1% accuracy. I
>do not see any frequency shift from streamer to non streamer operation. I
>think the capacitive effect is very small if it exists. Since the secondary
>is isolated from the primary after the first notch (We have all raised our
>secondaries haven't we? :-)), any frequency shift would not affect the coil
>in any way (streamers tend to break out just after the notch point).
>
> Terry Fritz
>
>
>>From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
>> Richard, et al -
>>
>> I agree the TC operating conditions are different from the instrumented
>>conditions. The capacitance due to streamer loading, etc. would change the
>>capacitance (Cs) of the secondary circuit and change the operating
>>frequency. However, my tests indicate this change is very small.
>>
>> A much larger change in capacitance occurs when the toroid, etc . is
>>mounted on the TC. The change in toroid capacitance from the calculated free
>>space capacitance can be as much as 30%. This can create a large change in
>>operating frequency. The calculated free space capacitance should not be
>>used to calculate the operating frequency without a correction for the
>>toroid being mounted on the TC.
>>
>> My TC computer program ignores the streamer loading, etc, capacitance
>>because I did not have this information when the program was being
>>developed. However, the tuning indicated by the program varies little from
>>the actual tuning of the operating coil when the corrected free space
>>capacitance of the toroid is used. This would indicate the streamer loading,
>>etc. capacitance has little effect.
>>
>> Do you (or R. Hull) have any test data that would show how much the
>>streamer loading, etc. capacitance is and how much it affects the operating
>>frequency after the toroid mounting capacitance change is taken into
>>consideration? As I indicate above the operating frequency change for only
>>the streamer loading, etc. should be very small.
>>
>> I like to look at the longest sparks as the condition where the TC input
>>energy equals the output energy plus the losses. When the losses are the
>>lowest the maximum energy appears in the secondary circuit and the sparks
>>are the longest. In other words the longest sparks happen when the maximun
>>energy at the maximum potential occurs on the topload. The length of the
>>first spark depends on the potential and additional sparks are then modified
>>by the ionozation of the air. The energy and potential are related by
>> Joules = 1/2 Cs Vs^2
>>This should be multiplied by an efficiency if one can be determined.
>>Note that a large amount of power can mean large currents and low potential
>>producing short sparks.
>>
>> John Couture
>>
>>-----------------------------------------------------
>
>