jonnydavro;

You have a neat and interesting idea there. One good generator would be to use a permanent magnet battery operated cassette
tape motor. That is, turning the shaft mechanically rather than suppling any DC voltage to it and measuring the output
voltage produced

You would need to adjust the gearing (belt) ratio to maximize output. (that is; optimise the mechanical impedance)
Then you could use a variable resistor maximize the multiplication product of voltage times milliamperes.
for example you make a table of volts and side by side with milliamps. Then multiply those numbers together to
give milliwatts. You then pick the highest milliwatts that is your maximum power and the variable resistor setting gives
your setup's impedance resistance.

Then you could compare this output milliwatts with your input in milliwatts.
Who knows? you may already have an overunity setup!

If you have overunity you can come back to report it and we could discuss a converter to connect the input to output
to make it an official overunity self-runner. A true overunity machine.


:S:MarkSCoffman

@ mscoffman.Thanks for your suggestion.That method with the variable resistor sounds like a goodway to accurately measure output power.
@ Nightlife. Glad to have helped,let me know if you have any luck.
 
                                                                    regards jonnydavro.

Hi.I have had another look at my DC Bedini hybrid motor and updated it slightly resulting in very low current consumption and extended duty cycle at no expense to the battery.I now route only the bemf through the DC motor.This motor now runs using 3.5mA @12v.It will run on a lot less voltage as i have also run it with my joule thief and cap combo.
Here is a video and updated circuit.
                                                  Regards Jonnydavro
 
http://www.youtube.com/watch?v=P6Jc8mv6xeg

Hi Freepenguin.The circuit diagram and all components are posted in the previous post to yours.It is a simple motor to build and i am sure you will have a lot off fun experimenting,It sounds like you have a lot planned.Please keep us informed off your results.Regards jonnydavro.

Hi Freepenguin.The motor i have made is small and for proof off concept.It does not have the torque to turn a car alternator which requires a lot off torque to turn especially when under load.This motor could probably spin an identical dc motor top and tail fashion like i have done with my joule thief  DC generator.Here is a video off it to show you what i mean.
http://www.youtube.com/watch?v=5ynFm-JwYjY
If you want to spin a car alternator.The following  version off my DC  Bedini motor is probably better suited.
The DC Motor/rotor is wired where a slave coil would be.
The second Rotor is a free wheeling rotor and is powered by the power coil pulse and acts as an anti stall device if the powered rotor slows down to much.This motor produces a lot of torque (it will take the skin off your finger as i found out)for a not so big current draw.
Another interesting thing about this motor is the amp draw decreases under load.The meter in the video is showing amp draw of 360mA.the power supply is 36v 0.5a. The motor used is From a 24v electric scooter
Here is a vid
http://www.youtube.com/watch?v=NuPHWPai4uQ
I will try to dig the circuit for this out for you and when i find it i will post it.
Hope this helps.
                        regards jonnydavro

   I was looking for a gen head some time back and wondered as to the
use of a car alternator. I went to the rebuild shop and talked to the guy
there. He told me that you have to have 1500rpm for the unit to start doing
anything worth while. Full out put takes 5 amps input and about 4 to 5 HP
to turn it. A very lossy system.
   You may want to look into low speed wind gen heads as an alternative.
They will put out good power at around 500 rpm. Just pay attention to the
problem of cogging. A 9 coil 12 mag setup may well deliver what you need.
This paired up to a Bedini motor may well fly. I have not got that far yet. Just
let the motor wind up and then turn on the output of the gen head and then
adjust the base resistance to keep it there. Make sure to use fast recovery
diodes in the three phase diode set..

thaelin

Hi Freepenguin.The Big one was running off a dc adapter as i did not have 3 good car batteries.
Regarding the circuit.R2 is a resistor and the 1k and 20k are both variable resistors.I use 2 for tuning.
The magnets are 20mm x 5mm neodymium rods grade N38.
An ampmeter is important but i would not spend a great deal off money on one yet.Buy a cheap one first and that will give you a rough idea off whats going on and maybe get a better one later which reads TRMS values.
Another thought.As you are struggling to find materials,have you thought about building a Bedini Fan.This is a great project to start with and you will get results quick and you may have most off the parts lying about in an old pc power supply.
I wish you well with your experiments and keep us informed off your results.
                                                                                        Regards jonnydavro