Muller Dynamo

[e2matrix]

@lasersaber

Nice work!  Thank you for the update.

There is an inexpensive laser tachometer that works very well for $17 USD.  Worth every cent in a project like this.  Read the reviews.. only one on the following site, but test against top of the line model was good!
http://www.amazon.com/Professional-Digital-Laser-Tachometer-Contact/dp/B004Q8L894/ref=sr_1_12?ie=UTF8&qid=1307471029&sr=8-12

Tesla

If you're not in a hurry check fleaBay as you can get them for around $10 with shipping out of China - same model. 

@lasersaber - thanks for clarifying that and adding the MH info.  LOL some people will never get outside the 'matrix'

Regarding MileHigh I saw his last post on OUR.  Getting so defensive I couldn't seem to get this image out of my mind of a duck backpedaling.

[resonanceman]

In case there are still people out there still trying to find a good way to cut holes in plastic for the rotors

I just bought some forestner bits

http://www.lowes.com/pd_95059-70-PC1008_0__?productId=3047788&Ntt=forestner+bit&pl=1&currentURL=%2Fpl__0__s%3FNtt%3Dforestner%2Bbit&facetInfo=

The one inch bit makes a drop in fit for my 1 inch magnets......a little looser than I would like .......but workable.
The 7/8 inch bit makes a hole that is a good snug fit for some roller blade bearings I have.sitting around.

The 5/8 bit makes a good snug fit on 5/8 inch cold rolled steal

I prefer  using them with a drill press.......but I tried and they work well with a hand drill too.

gary

[chrisC]

Hello everyone,
Been working on my replication but im having trouble with the driving circuit posted by romero. First time i spun it up it ran but transistor got really hot and eventually blew. Rebuilt the circuit and blew another transistor. Tried three times now to rebuild the same circuit with a tip32c instead of tip42c (had a few on hand, ran out of tip42) but cant get it running. Transistor heats instantly.

Can someone confirm that romero's circuit works as posted? I'm getting really frustrated with it. Can anyone recommend another circuit to drive it?

On a side note, just like to say excellent work going on here and thank you to everyone for sharing there findings! And of course thank you to romero!!

@freenergy850

The posted driver is probably fine although you may want to limit the current going to the base of the TIP42C if you use that default Hall sensor.
I can't get that Hall sensor and had to settle with a readily available OH180U from my local electronics store; they are similar, usually open collector on Pin 3 and in my case, I just pulled it up with a 10K resistor. Here's my sketch. Hope that helps.

cheers
chrisC

[i_ron]

The circuit is fine there are many many replications now with no driver problems so that means you are the only one to keep blowing transistors:)

It is a borderline working case of a really  bad design. It has been reported on before. The base of the PNP will easily outflow 2 amps or more... into a hall device rated at 20mA. 

Normally the PNP would be connected to the supply and thus would have the full potential of the battery available, but in this case it at least has the coils as a limiter.  Rather than champion this basket case, breadboard it up and see for yourself... you GROUND the base to turn on the transistor, right? well you will find that you can nearly weld with the base pin output.

Ron

[konehead]

Bolt wrote:

"Now watch your scope! you will get that perfect waveform with critical tuning. Requires EXPERT RF tuning to get this right. Then you are almost there to release the short circuit on the DC side of the bridge and let the power out to the dump cap. Then tweak the backends magnets again changes the inductance to suit the load."

Kone replies:
Can you give description the perfect waveform to be looking for?
Just like Romeros soocpe shot posted awhile back?
Should a dual trace scope be used, one trace on volts other on current to see the lagging?
Is the lag-period important part of it?
What would an expert in RF be looking for scope-wise?
As far as what "tuning" process is, is this pretty much just the distance of the regauging/helper magnets to the core as the tuning-adjust??
And/or does tuning also include whatever the resistive load is and rpms and maybe other things like arigap between rotor magnets and cores?
dumb questions sorry!