Muller Dynamo

[crazycut06]

Crazycut,

Well,  you have consider the frequency adjust potmeter as an R1 resistor value, besides the capacitor.   Generally an RC time constant is to be considered, the smaller the R  or/and the C, the higher their (1/R*C) value i.e. the frequency. For the 555 timer there are equations to determine the output frequency or there are charts to figure out the approximate frequency. 
Here is some charts to see some R and C values: http://www.williamson-labs.com/555-tmg-charts.htm  There is a tutorial on the 555 in their pages too.

IF you really need 2MHz frequency, then you have to use the CMOS types, like LMC555C or TLC555C because the old NE555 can run up to 120-150kHz only.   Here is a data sheet for a CMOS type, LMC555 and it turns out this type can run up to 3MHz in the astable mode and the capacitor is 200pF (minimum recommended value) and the R1 or R2 resistors are some hundred Ohms only.
see Page 5, maximum frequency test circuit:   http://www.ti.com/lit/ds/symlink/lmc555.pdf   

IF you happen to have a digital multimeter which is able to measure frequency directly, you may use such instead of a scope's frequency check.

Gyula

EDIT:  here is an online circuit simulator, showing a low duty cycle 555 circuit, slightly different than what I showed above but still practical and you can check the frequency too.  And if you edit the circuit resistor or capacitor values inside the Java applet, you can see immediately their effect ( just right-click on the component you wish to adjust).
http://www.indiabix.com/electronics-circuits/555-low-duty-cycle-oscillator/

Notice:  in this latter circuit when you vary the duty cycle or the frequency, then BOTH the duty cycle and the frequency changes.

Hi Gyula,
    Thank you for the reply, and this info surely helps alot....
Cc

[konehead]

Hi Mariu
I double checked today to see if the bakcing magnets were affecting the halls, and they are not affecting them.
Also fooled around with the backing magnets again, and now the 12-Magnet rotor motorgen has stacks of five  1/4" thick magnets in the stacks all around it now, except for the bottom-plate motor coil, and that has 6 magnets in its stack.....so it looks more "normal" now with long stacks of magnet coming out of the back of each coil's backside.... but what happened is that one of the generator coils should have its backing magnet-stacks on each side of it of the opposite polarity of the rest of the genrator coils. I remember Romero saying that not all his backing magnet faced the same way on his machine too - I will guess this is because of the odd vs even thing going on (12 N rotor magnets and 5 coil positions)
By retarding the timing, I can get it to go 1140rpm, and it draws 55ma and 12V....if I advance the timing, it will go 1320rpm but then it draws 90ma and 12V not sure which is better but it seems like the lower draw 1140rpm handles a load on the shaft better.....and I doubt the genrator coils make that much more power with with 180 rpm more...that is increase in draw of .42 watts for the 1320rpm, as it draws only .66 watts at the slower speed and 1.08 watts at higher speed....

[mariuscivic]

OK Konehead; that is  interesting what's going on there...
Lets say that you are running your dynamo without the backing magnets. When you start adding them, does the input power goes up and then stabilise or stays always the same?
If the input power stays the same then you really have something there( i dont think anyone  had this effect before) (then I'll kindly ask you ALL the detaills of your dynamo  )

[crazycut06]

Hi Konehead,
   
     I beleive that romero did a reversed or vice versa polarity backing magnets (or maybe not), to compensate the cogging, im thinki'n lets say coil set#1 has a north polarity on top & south below, (N-NS-S), as the rotors magnet aproaches the coil with core, the attraction is nullyfied (with correct adjustment) then coil set#2 has a south polarity on top & north below, (S-NS-N), as the rotor approaches it is being attracted towards the coil with core (again with correct adjustment) experiment this all around the coils to get best performance in rpm and power in vs power out, my point is its making a push and pull action thus helping the rotor to spin more freely, and maybe this confirms your findings on your motorgen. don't know if it would be the same when the coils are loaded.
   
     Romero did mention (don't remember what post is it) that faster does not mean its better! what do you think kone?

[Khwartz]

Hi Konehead,
   
     I beleive that romero did a reversed or vice versa polarity backing magnets (or maybe not), to compensate the cogging, im thinki'n lets say coil set#1 has a north polarity on top & south below, (N-NS-S), as the rotors magnet aproaches the coil with core, the attraction is nullyfied (with correct adjustment) then coil set#2 has a south polarity on top & north below, (S-NS-N), as the rotor approaches it is being attracted towards the coil with core (again with correct adjustment) experiment this all around the coils to get best performance in rpm and power in vs power out, my point is its making a push and pull action thus helping the rotor to spin more freely, and maybe this confirms your findings on your motorgen. don't know if it would be the same when the coils are loaded.
   
     Romero did mention (don't remember what post is it) that faster does not mean its better! what do you think kone?

Hi Crazycut!
Thanks for sharing your ideas.
May I ask you what means "cogging" here. i've checked in translation dictionaries on web and they say it's about "teeth-wheel", there is no here, so could you help me to understand in which mean you were using it please?
Cheer.