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Re: My Secondary

On the subject of extremes I was interested to see this from Scott 
White.... 

> I wrapped the coil around a 4' long cardboard tube with 8.5"
> diameter. I did not paint it with any kind of finish to make it
> more of an insulator. I also made a rather larger mistake in using
> (and this is the kicker!) #34 wire. So now I have a 4' long 7000
> wind inductor and I was wondering if there is any way to make a
> working tesla coil out of this or do I just have a big piece of
> junk. Any suggestions would be grealy appreciated.

My suggestions: I would try it out of sheer interest before pulling 
it apart. BUT, I think the tube should be thoroughly dried and 
impregnated with varnish before firing. My guess is it would smoke at
any appreciable power level due to the thin wire insulation (volts 
per turn). I calculate : inductance about 1.7 Henries!
                       : self capacitance about 19pF
                       : bare resonant frequency about 28kHz !

    I would expect its Q to be moderate due to the high wire 
resistance and cardboard. But I reckon there must be a hundred and one 
interesting experiments you could perform with it and I would love to 
hear from others who have contemplated things to do with low 
frequency coils.
    Ny prime suggestion : acquire a more suitable former for a serious
coil and in the meantime, let's see what ideas there are for this
somewhat unique opportunity. For example, if you tuned it to 8Hz with 
a capacitance of 233uF, you could "listen" in to the earth's natural
resonant cavity (guess). Extra capacitance of 130pF (additional to the
19pF self-C) gets it to resonate at 10kHz (within hearing range). I
must admit to wondering what a coil really sounds like :)

What do others think??

Malcolm