Re: C of Earth...

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>

Hi Jim,

Neat!  Assuming we are running 100MW at 20MV at 5 amps and assuming we can
loose 20% of the power on the way (we are desperate after all :-)), Ohm's
law says that the resistance needs to be less than 800,000 Ohms.  Thus 10
ohms would be great!  In fact, we could use the ionosphere as a very
conductive top load then with a giant capacitance to drive the frequency
down to the magic Shumman resonances if that is even needed.  That big one
at around 7Hz looks good:

http://image.gsfc.nasa.gov/poetry/ask/a10799.html

Having a very low resistance like 10 ohms is really important because when
the load of the city is put on the coil to transmitter voltage is going to
drop like a rock.  A prelude to horrible problem #2 :-))  The low
resistance may also be able to be sacrificed for a lower altitude since
getting tethered terminals up to 80kM is going to be a terrible problem
(#3) all in it's self. 

I think the number 800uF was introduced for the capacitance so the
inductance needed is...  646mH  Not bad at all.  It would also appear that
the ground is conductive enough that we would not need the giant copper
ground strap.  If the low ionospheric resistance between our to terminals
hold true, then we can worry about the loading the city will place on our
system.  One must wonder with such low resistances if convention high
voltage equipment at 60Hz would do just as well...  DC current is probably
not an option due to the problems in transforming the voltages.  Would not
want to repeat Edison's mistake again :-))

Cheers,

	Terry


At 01:30 PM 5/7/2001 -0700, you wrote:
>>From NRL Plasma Formulary, 
>Plasma Properties: 
>http://wwwppd.nrl.navy.mil/nrlformulary/typical_plasma_parameters.pdf
>Figure of above: http://wwwppd.nrl.navy.mil/nrlformulary/p41nrl.pdf
>Ionospheric Properties 
>http://wwwppd.nrl.navy.mil/nrlformulary/ionospheric_parameters.pdf
>
>The above shows that the ion density in the ionosphere is around 
>1E4-1E6/cubic cm, compared to 1E7-1E10 for glow discharge.  The ionization 
>voltage of the ionosphere is also much less than that in the glow discharge. 
>High pressure arcs are in the 1E15-1E17 range.
>
>based on this, I'd guess the "conductivity", such as it is, of the 
>ionosphere is around 1E10 worse than a high pressure arc, which is an OK 
>conductor, but not great.
>
>however, looking at the AGU chart you linked, it looks like the conductivity 
>of the ionosphere is comparable to that of the earth (sigmaE shown, looks 
>like 1E-3 (ohm meter)^-1) Typical ground conducitivities are something like 
>5 millisiemens, from what I recall.
>
>Anyway, using that 1E-3 number, a stripe that is, say 100 km long (i.e. 1E5 
>m), 10 km wide (1E4 m), and 1 km thick (1000 m), would have a resistance of 
>1E3 ohm meter * 1E5m/(1E4m * 1E3m) = about 10 ohms. 
>
>Tesla list wrote:
>> 
>> Original poster: "Terry Fritz" <twftesla-at-uswest-dot-net>
>> 
>> Hi Jim and All,
>> 
>> Seeing How Tesla was sort of desperate to get the energy transmission thing
>> to work, I have been thinking of ways to help out ;-))
>> 
>> I found a chart at:
>> 
>> http://jupiter.agu-dot-org/epubs/jgr_space/ja9905/1999JA900056/f04.html
>> 
>> Which implies that the conductivity of the ionosphere is fairly good for a
>> very high voltage low current system.  However it does not give the units
>> well unless it is saying 100 ohm/m^3 as a volume resistivity???  This is a
>> pretty important number to know to within a few orders of magnitude.  If
>> the resistance is too high, we are just going to make pretty lights in the 
>sky.
>> 
>> I can just see the thing making on ionized path between the two stations as
>> in the picture at:
>>
>