Joule Thief

[jeanna]

@ jeanna

Perhaps a single pulse will not light the bulb with only a 0.1 uF cap. I never tried just using a cap, I have always used the scr pulse circuit. In the attached video the bulbs are being pulsed with a 2 uF cap, so I know that works ...

I guess I didn't think the scr was more unusual than having 1000 pulsing volts, or I was hoping that anyway.

I used a 1uF earlier, so now,  I could put 2 in series and see, but I believe the diode was blocking this because there was no oscillation if I put the scope probe at the diode point but not including the cap.
However, I will give it a try once again. And try another diode too.

Incidentally, I do not think warming the CFL will make it brighter. I think they are brighter when working from the wall because they are getting more current.

Some of it may be current, but not all of it.
If you lived in a colder climate you would know that much of the brightness is heat related. 
I have several that struggle to go on in the morning; then they are very dim, but in 10 minutes they are blazing bright.
Sometimes, you can see where your fingers leave warm spots on the cold bulb. Not later, of course, but when it is still cold.
This is what never happens with the jt HV lighting arrangement.

I am happy with 1000v for the cfl. It is bright enough.
but the LoA bulbs are much brighter per volt and when 1000 v can light 2 or 3 the room is brighter lit.

Again thank you,

jeanna

@ist,
Thank you.
I look forward to the video.
j

[innovation_station]

ya !

i bet it is a kick a$$ b cap charger too ...


just another thing on the pile... 


yay! 

what is the out put of a standard cfl?

volts and freq?

!

btw the sparks i demo ... may just turn you off what im doing ..... 

; )

there not as lould as my neo zap but close ...  and theres no NEO THERE YET!!! 

I YI YI

LOL

I HAVE USED AS MUCH AS 20VDC 4 AMP TO SMAK a neo ..  and lite bulbs ... and i bet i can do it with this unit no cfl ... lol  with cfl ... not sure if im brave enough to try it !!!!!!

as i smoked mots with 4 amp ..  and a neo ...  litterly smokey room! 

[Pirate88179]

IST:

Do you do anything else besides build electronic devices?  I would love to come visit you one day and see all of your projects.  I have said many times here that you have wound more toroids than I ever could if I wound 24 hours a day for the rest of my life, ha ha. (It is true)

I am glad you are here with us.

Bill

[innovation_station]

its starting to get boring ..

i had to teach .. my tricks ...

share ...  ya know

now im getting sick of the things i have made my own .. and reclaimed ... 

cuz i cant even give em away ... 

sad really ...

all i hope is others learned the knowalage ...

peace ..

W

i some times solve age old riddles for fun ....   to pass the time ... 

got to be more to life than i currently have known ... 

teleportation bairly intrests me any more ... 

star gates so what .... 

another silly riddle ... 

any how 

dont even want the peace prize any more ...  lol 

maybe AG  .. cuz i never did it yet .. but it seams super simple too ...  espically if i use the switch it !

but i hardly see my kids ..  so i spend my time here ...  and when i do all they want to do is build things ... 

so i build!

im UNCLE BUILD! 

: )   

[crowclaw]

@ Jeanna,

I have had a look at your pics. Your CFL is lit good and bright from your JT, your are producing  very high voltage positive pulses... exciting the mercury atoms to produce short wavelength ultra violet light. You then appear to place a series connected diode with a capacitor at the output across the CFL. You are effectively smoothing out your pulsed DC to produce a steady state DC output? the CFL won't light, neither can I quite understand what you are trying to do here. So let me try and help you understand how a  capacitor charges. Look at XEE2's circuit, depending on the value of your capacitor in micro farads, will depict how long it will take to charge up and likewise discharge. Larger values of capacitance will take notably longer to charge. When the capacitor is fully discharged and then connected to the output of your circuit it represents quite a low impedance or resistance to the inflow of current to charge it up. OK depending on your JT coil configuration the circuit will see this as an initial short but recovers as the capacitor starts to charge up. This situation is the time constant, the length of time it takes for a capacitor to fully charge and of course discharge. The charge stored in a capacitor is measured in coulombs ( Q=CV) which is proportional to the capacitance and the voltage being applied. The measure of capacitance is how much charge it can store per volt. Next consider a capacitor can release it's charge at a much higher  current than that used to charge it, but cannot supply a higher voltage than that which charged it. By discharging the stored current energy from your capacitor  into a low resistance load such as a filament etc. you may see that filament glow for the period of time taken for the capacitor to release it's charge. Now then_ if you can replenish the charge and repeat the process you will see the filament flashing. Remember its all to do with time constants... how long it takes to charge up to how long it takes to discharge.
Always take into account the maximum working voltage of your capacitor. Capacitors can be series wired to increase their voltage handling but the total value of capacitance will be reduced... for equal value  capacitors in series the capacitance value is half which is the opposite for parallel combinations.  Hope this information helps you. Merv