The Ossie motor

[Jimboot]

Have tried Ossie but with two coils only.
Seems ok, running for long time; maybe with 4 coils it gets better…
http://www.youtube.com/watch?v=6EZKxu5qTJI

Wow very impressive! Are the blades sitill on that fan? Wouldn't the drag slow it down? Great work.

[Jimboot]

Can someone direct me to a resource that explains in principle how to replace a battery with a cap? I need to understand principles etc. Thanks.

[futuristic]

Hi.

First you must get a good capacitor. I suggest this one (22 Farad 2.5V Super Capactor):
http://www.jaycar.com.au/productView.asp?ID=RE6704&CATID=51&form=CAT&SUBCATID=861

Then you must charge it. Make circuit of 1.2V battery, 5 Ohm 10W resistor and 55F capacitor in series like in the attached circuit.
Double check the + and - on battery and capacitor.

After 5min the capacitor will be fully charged and you can just replace the battery running the motor with this capacitor.

Have fun
Frenky

P.S.
Some resources:
http://electronics.howstuffworks.com/capacitor.htm
http://hyperphysics.phy-astr.gsu.edu/Hbase/electric/capchg.html

[woopy]

good morning all

@ Gyula

thanks very much for deep explanation . I am at a good school here.

Here enclosed the current test with a 100 ohmn resistor at the entry . The motor spins much slower as expected  and the trace is much better on the scope.

and now the question  what does exactly shows this trace ??  pulse output from battery or pulsed input to the battery       is it showing the voltage or only the image of the current ??

@ Futuristic

Hehe Frenky you are a celebrity now      well done      and thanks for sharing

@ Jb

Futuristic made a good explanation for the supercap
here a picture how i hooked my 2 x  10 F 2.7 volt supercap in serie to get 5.4 volt nominal  because i use a 4.5 volt battery. If your battery is 1.5 volt you need only one.

I don't know if 10 F supercap is perhaps too small capacity because the tests i made with them are not very impressive . I can notice a slowing of the motor after some minutes already. Is there perhaps too much resistance in this small supercap ??  Any idea ?

i am still waiting my schottkys

regards

Laurent

[futuristic]

Voltage on the capacitor is dropping exponentially with time: http://hyperphysics.phy-astr.gsu.edu/HBASE/electric/imgele/capdis.gif

So if you don't recharge capacitor effectively the motor will quickly slow down due to weaker and weaker field B of the air coil.
This test should probably be done when you are positive that current going back into power supply (battery, capacitor) is bigger than current going out.

Frenky