Quote from: mondrasek on July 11, 2011, 02:15:24 PM
That's too bad.  Without knowing the inductance I don't think we can conclude that the bi-fi gives a greater output in general.  Good that it does in your case.  But a difference in inductace can be what is leading to the voltage increase and not the fact that they are bi-fi.

I found that my inductance varied quite a bit depending on the "quality" of the ferrites.  And so I inserted them to the proper location to make the inductance all the same in order to try and isolate variables.  Unfortunately that resulted in the ferrite projecting at slightly different distances out the side of the coils facing the rotors.  Due to the variation in attraction of the rotor mags to the ferrite now at slightly different distances that this inductance matching caused, that ferrite to rotor mag "cogging" vecomes a variable.  But with the slight differences in rotor magnet strength and positioning I think it almost impossible to eliminate all of that cogging and just understand a variable is there.

Last time I needed to purchase a DMM I made sure to get one with L/C measuring capability.  I highly recommend that if anyone is looking for another meter.

M.

When I started I didn't know nothing about all this stuff. So I purchased the next cheap meter I could get. Most probably I will get one with L/C caps after my short trip.

But I am aware that the coils are having different inductances. On my second bifilar coilpair the output is a wee bit smaller. I don't think that's a big issue if the variation is small for now. If I should get to the point to be missing 0.1 Volts in the end I will try and rewound my worst pair of coils. For now the next step is to make all generator pairs bifilar and also connect the last two coilpairs which I havn't yet. Then I can compare those as well.

Oh and about your question, I guess it's tesla style. I split both ends into 7/8 strands, and connected the 8 of left side to the 7 of right side.

Quote from: chalamadad on July 11, 2011, 02:43:51 PM
When I started I didn't know nothing about all this stuff. So I purchased the next cheap meter I could get. Most probably I will get one with L/C caps after my short trip.

I too was fairly ignorant about all this stuff a couple years back.  But following different threads in the forum leads me to useful information as well as forces me to research many subjects just to keep up.

Here is a useful link if you have not already discovered:

http://www.coilgun.info/mark2/inductorsim.htm

I was using it recently to check what inductance I could expect if I went to a smaller gage wire in order to increase the wraps and therefore the output voltage.  Unfortunately the resistance was doubling as well and I am not sure which effect wins out.  So I am continuing to test with what I have and will not order a different size magnet wire until I have convinced myself that I must.

If all of your other variables are the same and you only changed from unifilar to bi-fi I find it very interesting that your output voltage went up so high.  Do you have a way to check the current output to a load on coil pair before and after the change to bi-fi as well?

@Baroutologos . Reference the Italian magnet Boy . I know that James Randi is not popular on these forums , but he has investigated and debunked several similar claims . All you do is sprinkle the human magnet with talcum powder and the "magnetism" disappears . The objects are just sticking   to sweat , and possibly some substance smeared on the skin . Notice that some of the attracted objects are non magnetic coins . Come on now , we stopped burning witches some time ago .

Quote from: mondrasek on July 11, 2011, 03:35:30 PM
I too was fairly ignorant about all this stuff a couple years back.  But following different threads in the forum leads me to useful information as well as forces me to research many subjects just to keep up.

Here is a useful link if you have not already discovered:

http://www.coilgun.info/mark2/inductorsim.htm

I was using it recently to check what inductance I could expect if I went to a smaller gage wire in order to increase the wraps and therefore the output voltage.  Unfortunately the resistance was doubling as well and I am not sure which effect wins out.  So I am continuing to test with what I have and will not order a different size magnet wire until I have convinced myself that I must.

If all of your other variables are the same and you only changed from unifilar to bi-fi I find it very interesting that your output voltage went up so high.  Do you have a way to check the current output to a load on coil pair before and after the change to bi-fi as well?

Thanks for the link. Don't need it right now but bookmarked it.

Yes, I can compare this because I still have the unifilar coils on board. When holding a 25 watts lightbulb to the rectifier output the ampmeter showed 0.4 amps with the bifilar w/o cap. Think the unifilar was at least the same but I'll have to repeat the measurement since I don't remember it exactly. The rotor decelerated quickly @both.

Edit: Quick update, output unifilar is 0.8 Amps peak then goes down with the rotor slowdown to 0.7-0.6 Amps

I managed to build a small  muller generator with 6 magnets on the rotor and 10 coils, 5 on each side.
I am driving it with just one set of coils.the strange thing is that from each set of coils I get about 7.2 volts then if I connect 2 coils together after the bridge I get 9.8 volts and having them all connected I get 14.4 volts with 1k resistor as load.Why is that? I was expected to have the amps increased not the voltage. Normally if we add 2 or more batteries in parallel we always get the same voltage and increasing only the amperage.Each bridge rectifier I built from 12 1n4007, 3 for each side of the bridge.
Any ideea?

David