Bismuth core Joule thief

[Mk1]

@jadaro

Hi , i would make a plaster (plaster of Paris) you don't need one that goes all the way around , i would put soap over a toroid first then make a mold ...

Good luck !

[phoneboy]

Word of advise, if using plaster for yor mold dont completely fill it as bisthmuth expands as it cools, you'll break it.

[CLaNZeR]

Try wood for your moulds.

Worked okay for me

http://www.youtube.com/watch?v=NZF1FYaEdqc

Cheers

Sean.

[sm0ky2]

Try wood for your moulds.

Worked okay for me

http://www.youtube.com/watch?v=NZF1FYaEdqc

Cheers

Sean.

you want to orient the diamagnetic field as its cooling.

my thoughts on this are to space the "moulds" out a bit,
and place a ceramic "magnetron" ring underneath.
-those big donut magnets from inside a microwave.

[resonanceman]

I  have completed a few tests.
I made a mold using a 5 for $1 toroid as a plug.

I did not  get the bismuth  toroid to work as a JT

I was not surprised that  it did not work........ my main interest  was  the possibility   of a bismuth  toroid  adding an extra pulse or something to an impulse.
That did not happen...at least not using low power.
The picture  is  of a test that I did  using 4 candy cane  coils that I made.
All the  coils and the primary are connected  start of  one bifilar wire to the end of the other.....
The  primary is one piece of wire running through each coil  ( 5 laps )
I tested  then with 1 AA  ( 1.34 V )   and 4 AAs   (5.17  V )

Across the primary I got  6.14 V  and 11.92 V
Across  the  coil  with 3 toroids I got  2.87 V  and 5.49 V
Across the  coil  with 4 toroids I got 3.94 V and  8.40 V
Across  the coil with 5 toroids I got  5.30 V and 10.25 V
Across the  coil with 3 normal toroids and one  bismuth  toroid  I got 2.72 V and 5.26 V
My conclusion  is  the bismuth  toroid slightly dampens the output  of  the coil ........ at least at low power.


gary

Edit
I do not have the equipment to accurately measure the  power  of each  coil ....
It  is possible  that  the bismuth  toroid may  be good for  getting more power out of a circuit by converting some  voltage into current.

I did a test  with a red LED
using 1 AA  and 3k base resistance the  4 toroid coil  will just barely light the LED  ........ with  the same setup  using the  coil  with the bismuth toroid the LED is at least twice as bright.
I  could not  see a difference at higher power settings.......
Even with the 4AAs I could not  get any of my LED arrays to light  with either coil.