Joule Thief

[innovation_station]

well i had my fun with the nano mk2 jt ... 

so i guess i will finish the 6 pac.. it is almost done anyhow ..

@dog

you hula hoops are not too cheep .....

so i dont know 15 -20 bucks a unit ...    but if you just want a tuned coil and no led then im sure we can get it down to 5-6 bucks each....

if you were thinking a buck or 2 im NOT INTRESTED ..... 

LOL

I BET NOW YOU SPEND OVER 20 BUCKS ON WHAT IS INSIDE THEM ....  WELL THIS WAY YOU DONT NEED A CHARGER...

THROW IN A FEW SPARE BUTTON CELLS ... 

ANYHOW...   I GOT MUCH WORK TO DO ...,

IF YOU WANT THEM THEY ARE DESIGNED TESTED AND WORKING ...   

[Goat]

Hi Thank you for the reply .good work on your Mod and winding that extra coil . its interesting that you said the Fugi mod is putting out what is putting in . thats two people that said that . there must be an error however its not mine at least on the mod part . the pictorial from goat works on mine . . You can get results If you simply change out the 220 resistor next to the transistor with a 5k to 20 k pot and short the diode .hook up a modded cfl to the Hv cap output with the cap removed . Stop there and you should have a gutted Cfl Lit if no then there is a Short .only go this far before you continue ! . ok   .. I have done My mod many times  exactly this way no problem . . there is a spot on the board that one lead from the pot  is soldered to and it will short if not careful Its very close to another connection .I have done this and found it shorted .. . anyways try that . forget the diagram for now just do the above only if you want to get it running .  . then proceed if Modded cfl lights .  If you find that the error is Mine please let me know on that Picture of the Lines pointing to the area in question .. Like i said before i just build them and try to do the best at showing where the connections are . I have used that picture of goats and have replicated it several times but maybe theres a slight difference . so forget the diagram and do as above first ..

Gadget ..

Well I'm on my 6th Fuji mod and still no go, one thing I've noticed is that not all boards are made the same, out of 6 only 2 were made the same.  Also, out of 6 only 1 had a D1960 transistor.  Some have LEDs instead of NE2s, others have the 4th transformer pin soldered while others don't, some have all 4 pins soldered on the trigger transformer while others only have 2 soldered, and on and on....

I think the best thing would be to get the components off the original Fuji cct boards and onto a separate cct board and start from point A to point Z until we can nail it down to a perfect setup and avoid all these discrepancies between the original circuit boards.

I looked for a datasheet on the D1960 transistor on the web but couldn't find one (D1961 and up), it's also not listed in Jeanna's "Transistor specs for transistors database. Information on Transistor prefixes of 2N 2SA 2SB 2SC 2SJ 2SK 3SK and more.pdf" so if it is a requirement to making it work we need to find an equivalent substitute.  I found a site where someone listed using the BC 337 and/or D1960 transistors but without the specs of the D1960 it's hard to tell if they are the same.

At any rate, the closest I got to an output higher than 1.5V while adjusting the 20K pot was not enough to light a CFL but was giving really strange outputs on the DMM, I would get an overload at the 20 VDC scale but only 1V at the 500VDC scale!  If I set the DMM at the 500 VAC scale I could adjust the pot to get as high as 64 VAC.  I just replaced the battery in the DMM and same results so it's not the battery and my other DMM confirmed the same results....

Edit:  In case of confusion for beginners, the D1960 listed above refers to the 2SD1960 transistor, on the Fuji circuit board it is marked as D1960.

Regards,
Paul

[hazens1]

Here is proof a 555 timer circuit can operate on really low voltage. This one is operating on only 0.973v thats under half the voltage needed according to the timer's specs. The leds are dim, but the circuit is setup for a higher voltage and playing with components can yeild a brighter led or if I ran a single led instead of 3 in series.

[innovation_station]

when i bought my RS junk... i got about 300 chips..... 

dont know if they will be of use ...

they are latch gate chips...  or something like that .....

ill get the part # 

i never checked out there use yet ...


this is what they say 

74hct175 quad d-type flip flop with reset ..positive edge trigger ....

hummmmm  they are 16 pin chips...

ist?

soooooooooo     at a closer look at the chips i have a few diffrent ones..... 

this one is 20 pin ...  it says  74hct373octal d-type transparent latch 3 stage....

then it says under it  high speed cmos logic device ...

[gyulasun]

@gyulasun
   Thankyou, i have double checked the results, i had to,
for my own Peace of Mind. I am a little fuzzy on what is Happening
with the third winding, if you have the time and are able to explain
this to me more, it would be greatly appreciated.

The equations you have done in your reply will be very helpful, thankyou.

I also hope to show how i got these results tomorrow, just got to
get it from my head to the screen.     

@mikem_2au

Hi Mike,

Thanks for your kind answer.  I think what the third winding does is connecting the flyback pulse once again in series with the already rectified flyback pulse so seemingly two voltage sources are added in series. Flyback pulse is created when your transistor switches off the current in your 8 turn coil (or with whatever # of turns) and the collapsing magnetic field induces voltage in all the coils on or close the core.  So you seem to peel off at least two skins from the beast   

Regarding your answer to xee2, I am a bit suprised because I automatically assumed you wrote the LOADED value of the output DC voltage (21V)  at the load currrent of  27mA...    And now it turns out you measured them separately?   If so, please use two multimeters for testing: first at the input for the current and the voltage while you have your load on the output,  then  move the meters to measure the DC voltage and current at the output on the same load,  ok?
Because my calculations I have shown on the COP has any sense in this latter case, otherwise it is meaningless, sorry.

Thanks,  Gyula