Muller Dynamo

[From other Planet]

The earth ground thing is something i am also thinking off.
One possibility of function could be the generating coils do not only induce voltage from moving rotor magnet fields, but perhaps also act as very effective radio receivers drawing energy from surrounding em waves.
Only an idea

[rfmmars]

Eureka!

I adjusted my rig again to bring the o/p voltage a little higher by moving the output coils closer to the rotor.  I aimed for 10 V ptp on a single coil.  But I may have over shot a bit.  Unloaded max dump cap voltage was 9.85 V, which is a bit higher than was expected.  But as I moved the coils closer to the rotor I have more variation in the wave forms, and also I had to switch down the V/div seen on the scope, thus lowering my screen "resolution".  So harder to adjust to an exact V o/p.

I began running the same series of output tests by attaching the same resistor loads to the output cap.

When I got to the smallest resistance test (49.1 Ohms), I noticed a curious thing.  I could not get stable readings on the Vout, because every time I would touch the DMM probes to the load I would see a rising voltage.  And then I realized that I was also hearing an increase in RPM!

I confirmed the increase in RPM with the laser tach.

I then wanted to see the wave forms but found that attaching my o-scope ground also caused the RPM to start increasing.

So please let me know what a load "sees" when a DMM set to read voltage is exposing.  Also, what does only the ground from an o-scope probe do to affect anything?

I tired dropping the load Ohmage further and found the usual RPM drop.  But then I added a 1 Ohm precision current shunt (resistor) in series to increase my load by just 1 Ohm and saw an RPM rise.

49.1 Ohm (measured) Load = 1835 RPM (I cannot measure other values without causing the RPM to change)

49.1 + 1 Ohm Load = 1841 RPM  Vin 14.96, Iin .407, Vout 5.22

I am thinking I need more 1 Ohm or less resistors to drill down deeper into this find.

Also, I was about at the limits of my resistor's power capacity.  They are 1/2W units and several combos were quite hot at this o/p power level.  So I need something that can handle higher power output as an adjustable load if I am to continue with this line of testing.

Gyula (or anyone else), do you have any better load suggestions?

Thanks,

M.

When using USB scope, you must do two things, first is to float the ground to the computer and power supply. What I do is cut off the ground pin on both cords and use a cap say 10uf from the scope's probes ground ring to project test point or project ground.

If you don't do this you can blow up the USB scope and the USB port on your computer, it happen to me.

Richard

[chalamadad]

Gyula (or anyone else), do you have any better load suggestions?

I have used a small dc motor as load before. Load curve is probably not linear when speeding up, but you can increase the load by manually creating drag to it.

Edit: What about a poti?

[chalamadad]

When I got to the smallest resistance test (49.1 Ohms), I noticed a curious thing.  I could not get stable readings on the Vout, because every time I would touch the DMM probes to the load I would see a rising voltage.  And then I realized that I was also hearing an increase in RPM!

I had the same effect. Probably the probes are not insulated well enough. Holding them stronger or even holding both probes in one hand can increase the voltage even. We are talking about 2-3 Volts additionally here. I think this is something to avoid and falsifies the record. You're putting body charge in or something alike. You cannot have that later if you want to test your self runner and not be able to have a cup of coffee because it's necessary to holding the probes all of the time. The wife will say "now he's gone completely nuts!". This is literally "freak on a leash"! ;-)

[neptune]

@mondrasec . How to make a variable load . Get some Nichrome wire . This is used in the heating elements of electric fires , toasters , dryers , also cooker elements but is harder to get out . Get it from a scrapyard or recycling centre . This wire can run red hot without damage . Now , with a length of this wire and 2 crocodile clips you can fine tune the resistance to within 1 ohm or less . You can add a series resistor to get it into the right range . Mount the nichrome on a fire proof mounting , or use it on its original mounting .