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30 BPS, 60 BPS tests
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From: John H. Couture [SMTP:couturejh-at-worldnet.att-dot-net]
Sent: Sunday, March 22, 1998 6:40 PM
To: Tesla List
Subject: Re: 30 BPS, 60 BPS tests
Bert, All -
Am I detecting that some coilers are beginning to consider the fact that a
single extra long spark may be due to more than one bang? In other words it
may take more than one bang of energy in the primary circuit to create the
extra long spark in the secondary circuit. More than one bang means that it
does not make sense to use the continuous input wattage with the extra long
spark in comparing coils. Of course, the problem can be solved by using
controlled (continuous) sparks.
What must be determined is the total amount of instantaneous energy in the
bangs that are involved with a particular extra long spark. This would be
the instantaneous input wattage x dt times the number of bangs. To my
knowledge no one has ever done this or even suggested a method of
implemating this kind of measurement. Are there any suggestions for making
these measuremts?
Apparently the exact process of what is going on in the TC system to
produce the extra long spark is not completely known. What is known is that
it could require the energy of more than one bang to create that extra long
spark. This means that energy from a previous bang is stored somehow in the
secondary circuit to be added to the energy from the next bang. Also known
is that there appears to be no indication in the scope waveform to give a
clue as to how the energy is stored.
One of the possibilities is that the ionized air channel of the previous
bang may be helping the process. However, this ionized channel has no
additional energy that can create a longer spark by itself. This extra
energy must come from additional bangs. Things like temperature, negative
resistance, etc. contribute to the overall effect but are not the additional
energy that is required to lenghten the spark. This energy can only come
from the input energy via the bangs in the primary circuit.
There is energy in temperature, etc, but to increase the length of the
spark additional energy in the form of voltage is required. The mechanism to
store this voltage or charge in the secondary circuit is unknown. The
voltage apparently is in the form of a negative charge because this can be
proven by tests. If this is a decaying voltage (or dampened wave?) the decay
may be too slow to show up on the scope. Has anyone done the calcs to find
the possible rate of the secondary RCL discharge compared to the period of
time between bangs? This rate would be dependent upon the inductance of the
secondary coil plus other parameters.
John Couture
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>From: Bert Hickman [SMTP:bert.hickman-at-aquila-dot-com]
>Sent: Thursday, March 19, 1998 7:07 AM
>To: Tesla List
>Subject: Re: 30 BPS, 60 BPS tests
>
>Varying spark length may be caused by a lot of parameters interacting
>chaotically and non-linearly with one another. Optimally-quenched and
>capacitively top-loaded disruptive coils seem to have an output voltage
>characteristic that's ideal for supplying heavy current to an advancing
>streamer during ring-up. Combine this with a rep-rate that permits
>partial re-use of the arc-channel blazed by the previous bang, and you
>now have the recipe for streamer growth on successive bangs.
>
>Eventually, a balance must be reached between power dissipated in the
>entire streamer versus the effective power supplied from the coil's
>output. At any given time, the streamer's length will be strongly
>dependent upon streamer root peak temperature, previous streamer length
>and "sinuosity", and a whole host of other factors. Because of negative
>resistance characteristic, higher current flow will tend to make the
>plasma better conducting, allowing the potential of the discharge
>terminal to extend "further out". The important thing is that the length
>of a given streamer will be a function of the past history of the
>channel even though the electrical events ("bangs") are independent from
>one another. To my knowledge there are no measurements of output voltage
>which have indicated the presence of any DC voltage between "bangs".
>This does not say that there aren't a whole lot of left over ions in the
>immediate vicinity of the coil...
>
>-- Bert --
>
>
>
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