Re: The Next Coil
From: Bert Pool[SMTP:bertpool-at-flash-dot-net]
Sent: Tuesday, July 29, 1997 1:02 AM
To: Tesla List
Subject: Re: The Next Coil
> From: Greg Leyh[SMTP:lod-at-pacbell-dot-net]
> Sent: Monday, July 28, 1997 3:25 PM
> To: Tesla List
> Subject: The Next Coil
> An opportunity has finally arisen to build a new coil from scratch,
> and hopefully benefit from all of the mistakes and discoveries made
> since my last coil design attempt, in 1990. Seven years is long enough!
Hurrah for Greg! We gonna see some BIG sparks now!
> Based on countless bits of information exchanged with people on the List,
> numerous PSPICE simulations, and many past mistakes, here are some values
> from the preliminary design set for the new coil:
> Top Capacitance - 130pF (96" OD space frame sphere, 28' altitude)
> The top C is where this coil design starts. I have finally bought into
> the 'huge top C' argument, after reading more about the microsecond
> structures present in lightning as the spark front advances. Even though
> the top C reduces the Vout directly, it appears that a local low-Z
> reservoir of charge must be present at the base of the streamer channel
> in order to solidly support the streamer growth on microsecond timescales.
> Adding a physical 100pF capacitor to my existing coil proved this out.
> -- Preliminary Design Values --
> Lsec = 120mH (37" X 154", 5 turns/inch)
> Fsec = 51kHz (no sphere) 36kHz (w/sphere)
> Cpri = 0.270uF (0.045 X 6 units)
> Vpri = 44kV
> Coupling = 0.22
> Max Break Rate = 400 BPS
> HVPS Capacity = 120kW (3PH to DC, resonant charger)
> Preliminary construction and testing of components is ready to begin, at
> a site inside the Hunter's Point Naval Shipyard, in San Francisco. This
> location was selected for its abundance of cranes and electrical power,
> its high level of security, and its remoteness from residential areas.
"Captain, our sonar AND loran AND radar have gone crazy! Any
suggestions as to what could be causing the problem?"
> I will post results and pictures as they become available.
Best of luck Greg.