[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Tube Coils.



Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 3/1/03 1:39:06 PM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

> >Original poster: "Paul Marshall by way of Terry Fritz
><teslalist-at-qwest-dot-net>" <klugmann-at-hotmail-dot-com>
> >
> >I have a friend who recently aquired (2) 3CX10000 Tubes. He would like to
> >make a tube powered coil. Does anyone have a schematic I could give him ? I
> >think he is planning on winding a 6" or 8" diameter coil...
> >
> >Paul S. Marshall
>
>


Paul,

Unless your friend has a lot of electrical power available, he may
want to use a pulsed (staccato) feature on the coil to reduce the
input power.  The size of the coil should depend on the desired
spark length.  I use the formula,

    spark length inches = 0.49*sqrt input power

for a tube coil.  So if 60kW input is used, the coil should give
10 foot sparks.  If you figure you want the spark length to be
twice the height of the coil, then the secondary should be 5 feet tall.
I've obtained spark lengths up to almost 4 times the secondary
length on tube coils, but flashovers may be a problem.  Perhaps
3 times the secondary length would be OK, making the secondary
about 3.3 feet tall.  Of course your friend could used just one tube,
or run the tube at less than its full capabilities, and keep the spark
length and power input lower.  If you want long sparks, then AC not
DC should be used for the plate supply.  Other than that you can
probably just scale up an existing tube coil schematic pretty much.

If he wants to limit the secondary to 8" diameter, then a height of
24" to 34" may be good, depending on the desired spark length.

I wouldn't recommend being too close to the coil when it's running
if he uses the full capability of the tubes. It will be a fearsome
beast indeed !

John