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Re: Calculating Sec. Voltage

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> Subscriber: rhull-at-richmond.infi-dot-net Mon Feb 10 22:02:25 1997
> Date: Sun, 9 Feb 1997 11:33:45 -0500 (EST)
> From: richard hull <rhull-at-richmond.infi-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: Calculating Sec. Voltage
> 
snip

> The voltage divider bit might work with a little 100KV coil, but at the
> higher level, forget it.  Where are you gonna' get resistors that won't
arc
> over at 4 meter arc levels!!!  If the voltage is on the order of
2,000,000
> volts, you wouldn't want to load the coil and so I would opt for a string
> that would draw no more than 100 ua max! That's 10,000 ohms per volt. 
Thus
> you would need a calibrated 20 billion ohm resistor, (2X10^11 ohm), over
15
> feet long to set up the large drop inseries with maybe a 10 kilohm
resistor.
> The big resistor would need to be capable of handling at least a couple
of
> hundred watts.

Sounds good, but:
Why 15ft long? If you can put the resistor into a place where the field is
high, but uniform, it shoudln't have to be this long to avoid arcing. I'd
stick
it into the center of the secondary coil where the field is say 2MV/1meter
=20KV/cm but we know that arcing does not occur. BTW you shouldn't 
have to worry quite so much about power dissipation since your average
power should be considerably less than this peak power of 200W. I think 
this problem deserves a lot of attention if we're ever going to know
what really going on with these coils. It's one step away from determining
something about the impedances of secondary discharges...

 


> Capacitive dividers might offer a much more doable form of divider.  It
> would still be a 5 meter long vacuum capacitor on the input end though.
> This would avoid arcing.   I have used the capacitive divider method on a
> couple of my micro coil systems. (under 3" arcs) . The small coils must
> always be retuned under load and the load must be well below 6pf total. 
The
> results were way below the "pie in the sky" estimates above.  The three
inch
> arc coil measured 28KV AC RF at 1.3mhz!!!!  This can't be used as a guide
as
> in 9.333333333 KV per inch to extrapolate to larger systems unless you
are
> into serious self deception.
> 
> Who measured this 3.5mv voltage again!!!
> 
Exactly.
If no one on this list has done it, it probably hasn't been done by
an amateur!

> Richard Hull, TCBOR