Self Running Micro TPU, with closed loop.

[hakware]

My Guess would be an FT140 or an FT240.. in a mix 77 it has the highest permiability. It would be nice to try some at each end of the scale
low and high permiability like a mix 61.
.

[wattsup]

@4Tesla

Thanks for the link.

I think @hakware is right about the Mix 77 since is has the lowest MHz rating, although it is probably higher then we are going, it is the closest.

If you look at my photo of my multiple coils, located here;
http://www.overunity.com/index.php/topic,3599.msg60877.html#msg60877

the FT240 would be like the back center coil although mine is slightly fatter, and the FT140 would be close to the back left and right coils. I don't think the FT 240 will be good for this circuit but it may be good for the same circuit working at higher voltages, simply because the saturation current required would be greater. I would say the best choice is the FT 140 77. But I will get a few of both also (just in case).

[4Tesla]

@ hakware and wattsup
Thank you!

@all
What do you think of the iron toroid cores?  Should I buy some?

Thanks,
4Tesla

[eon]

cap in coil:

1500uF 16v inside 30/15/7 x 0.6mm insulated tinned copper on unknown core (from pc psu similar to the original em devices model); RC: 1M & 1uF Tantalum, Switching: 2 x BC337 (safety in numbers); LED: blue unknown spec

6v: 5.49min, frequency steady (unknown), more rapid toward the end
9.6v: 7.47min, 0-2 mins slightly faster and dim, 2-7.3mins steady, brighter; last 10secs, brightest and slower.

its like it kinda tunes in as it goes, dont know if this is cause cap is in core, or just the voltage.

components are ripped from old pc for the moment, and i will make two duplicate halves when i have ordered better components.  interested (as others) in different frequencies (not just schumann, but higher?), but also fast switching, bemf and two capacitors...

[hakware]

@Tesla
I am not sure how the Iron cores are going to work out. they design the ferrite mixes to have the lowest eddy current losses possible. Iron, as I have read would display higher core losses.
Most ferrite cores are an iron, molybdenum nickel mix.

It is up to you. and it sure is worth a try on one. dont leave anything to chance I say.

@eon

The aluminum can/core in the capacitor is changing the resonance of the circuit as the field flux changes in strength.