Muller Dynamo

[Scorch]

Have you guys seen Rick's "new mini 4 dualpole motor"?
http://www.youtube.com/watch?v=XRZkRfZd03M

It appears he has built his own version of the Muller Dynamo.

Do not know what, if any, advantage there is using two rotors with one set of coils.
Seems like a waste of magnets to me. He could cut his coils in half and accomplish the same thing with half as many magnets and save lots of money.
It doesn't appear, to me, he is trying to accomplish any resonance or is demonstrating anything significant.

Is it just me?
Or does it seem like he always has dead batteries?

}:>

[DeepCut]

LOL !

I think they just like selling stuff ;+}


DC.

[Scorch]

Spent a couple more hours throwing together the simple hall circuit.
Tried to keep it as compact as I could squeeze onto the proto board.
Might try to get it running, soon, after I spend time staring at my work.
I am proud of the things I build and, sometimes, I like to just sit back and admire my work after I build something. 

I did ask ZFF if he thinks it might be possible to achieve a resonant system without cores or bias magnets.
He thinks it can be done but it would, likely, be at a significantly higher frequency.
Don't know if that's possible, or even wise, to attempt such high RPM from an experimental device like this.
I believe anything above 10,000 RPM would REALLY be pushing the risk envelope for catastrophic failure.
But I am of the belief a resonant system may work at more than one resonant, or sympathetic, frequency.
Therefore it may be just a matter of the proper tuning with the right diode/capacitor configuration.

Wish I knew more about how to tune such things.
And these sewing machine coils are not perfectly matched, I don't have an inductance meter, and wouldn't know what to do even if I do establish the inductance values of these coils.
I do have a scope, which helps, but the best I can do is trial & error without more knowledge and test equipment.

That is all for now.

}:>

[DeepCut]

I know what you mean about admiring the things we build

Looking good there Scorch, nice soldering, i am crap at soldering but i do have a rubbish iron that takes ages to melt the solder, so hopefully things ill improve when i get a higher quality iron.

I got a cheap inductance meter from ebay that i've tested against a friends good quality one and the difference is less than 0.25%.

It's useful to ensure that all your coils' properties are as close as you can get them.

What scope do you have ?

I was using my soundcard and a DIY probe, then i ordered one of those 2-channel/8KHz cheapies from China.

Turns out it doesn't do negative voltages, just goes from 0-5V, and it doesn't even zoom in on the waveform !

Guess i should have read the manual ;+}


All the best,

DC.

[DeepCut]

Here's the LCR meter i bought :

http://www.ebay.co.uk/itm/LCR-INDUCTANCE-CAPACITANCE-RESISTANCE-METER-TESTER-T86-/370320202231?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item5638cdd9f7


DC.