Joule Thief

[resonanceman]

thanks jeanna, glad the link helped.

@resonanceman
very small bobbin cores can be used with good success. i have a jt using a bobbin core that is a bit smaller in diameter than a AAA battery and 1/4 the length. i have access to a good camera now so if you want a close up of it, give me a shout.

WilbyInebriated

The  bobbins  I have are  about 1/2 X 3/4    I think  that is about as small as I would want to go
If  I use  magnet  wire  for the  primary  next time I should   have  a little more room for  secondary . .....maybe  I can  get by with  a couple less wrapps of the  primary  with mag wire  .


I   don;t  think I  will be taking many  pictures  until I  get  something  soldered together .
I use  alligator  clip leads  to connect everything together .......  It  takes   from  4 to  9 coils  to get to  a self  charge  state .....  I  find that  adding  another coil  often  gives me  between  a half volt  to 1 volt more ..... ( under load )
most of the time  I use  my LM coils  or  toroid JT coils ......  with these  I usually  connect  both the  primarys and  the secondary   for either  flyback or feedback .
So ....... you can imagine  how much of  a mess it  can be .....


I think my next  try  will be  with a flyback  transformer  core .
I remember  someone    used  one of these before .......
I am going to  try to  get  primary  secondary and   hopefully   one or  2 feedback  coils  all on there together .

after thinking  about it  a few minutes  I am     take  it apart  and    try to wrap about  200  turns on both the  rounded legs ........then I clip  it back together  and   wind whatever  I can on the   square  side ......

the last step is   adding  a MK2 primary .....  on the  ends .....  I guess my first step  should be to do a test and see how many  winds it takes   on each leg of the MK1 to make it work





gary

Edit

I  did not  try to  tune  it  ........but I am guessing  that 5 wraps each leg  is about right
It  lights  up  the  JT LED  at max  resistance of my pot .......2.5k      it  starts to sing  at  .70  A     The  pitch  drops  low enough it is hard to hear  at full power ...... 1.5A

Ooopps  ....that is with  2 batterys

[jeanna]

http://www.tb3.com/tesla/

Hi Wilby,

On TB3 site at the bottom of that page, there is a list of measured inductances.
Is there a meter for measuring inductance?
or, even better, is there a way to measure it with a dmm?

she said, hopefully.

jeanna

[WilbyInebriated]

Hi Wilby,

On TB3 site at the bottom of that page, there is a list of measured inductances.
Is there a meter for measuring inductance?
or, even better, is there a way to measure it with a dmm?

she said, hopefully.

jeanna

measuring inductance or capacitance is difficult at best without an LCR meter.
not as far as i know of with a DMM (some can measure capacitance).

i like primary form on his mini tesla from that link. i hadn't noticed it before. thanks, i might do mine that way.

[innovation_station]

heres my latest unit only for led lighting ...  works awesome ...


ist

my newest toy

[innovation_station]

about my last picture see above ...

what if i took speeker wire bifillar thin gage ..  and did 3 turns around each and compleated the loop at the 6th coil then jt ed the pulse coil with a 3055 and never taped the jt flyback so it is forced out the 6 inductors as step up transformers then grouped all outs togather as one after rectifering

ist

just looking for comments



yikes i may wind round and round and round then stop .....  hummmmmmm

ok im gonna use magnet wire .... bifillar

gonna use fone wire .. as primary