--- In MEG_builders@yahoogroups.com, "ccool_j" <ccool_j@...> wrote:
>...
> As you said, one of the important factor is to get the magnetic field
> from the magnet all contained in the core. Which is why (as far as I
> know) Metglas core should be better. Because of the huge magnetic
> permeability of these kind of core...
> I have been told that the magic would be happening when the core start
> to saturate...
> Anyway, to prove this "partial saturation" thesis, I'll need some
> better electronics, becaus mine is burning when the back emf from the
> input coils create voltage over 100Volts... (wich is about 30 volts in)
>
> I'll try to get something that works at 500 volts and I'll tell you
> how it goes. With that kind of electronics, I'll be able to reach the
> optimal +70 Volts that Bearden was talking about.
>
> Ccool
>
As the core goes into saturation, the field will be less contained in
it, so if good things happen when saturation occurs, it refutes the
idea that high permiability and low field fringing is needed. Also,
note that there are several formulations of metglas materials.
"Distributed gap" is another way of saying reduced permiability.

You can get the saturation you want without higher voltages, just
reduce the frequency. The magnetic field depends on the curent not the
voltage, so increasing the time and leaving the voltage constant
increases the current thru the inductor. If the EMF on trun off
(flyback) is too high, it is because of lack of load on the secondary
which should be tightly coupled to the core (atleast if it is to have
low fringing fields)