Joule Thief

[jeanna]

Thank you @jeanna.
You know, I am a visual person and to understand a new principle I need to look at some schematic. If you have any or any link that has them please post.

Jesus

mmm
Here is a link to the astable multivibrator.
http://www.play-hookey.com/digital/experiments/rtl_astable.html
It is a tutorial so you make it step by step on the diagram. There are others, but I like to get in there and do it, so this is like that but with no parts to drop!
It is a good site like that. good name too!

jeanna

[Pirate88179]

Been doing reports all day and I come here and I am even more behind!!!

IST:

Nice video, I gave you 5 stars.  I bet that will light the bulb only without the cfl circuitry, maybe give it a try.

@ MK1:

Yes, I have read about the trench radios used in WWI.  Some of them were tuned by sliding the graphite contact from a pencil down the length of the razor blade that was somehow used in the circuit.  I am willing to try any of this...once all my parts arrive.

@ Jesus:

Nice circuit there.  With what you know now I'll bet you can run a JT from it easily.  I think it was you that posted about the stores switching out the diodes on folks? (I wish we could go back a little more while posting so we can answer everyone)  Well, I ordered 50 of the 1N34 germanium and they had better be the 1N34's or I am going to call the folks I ordered from and send them back.  Thanks for the warning.

Jeanna:

You are getting there with your low power draw circuit!  I like Gadgetmall's take on power....same light, less mA's.  Hey, I just read something about silicon transistors in my electronics book....I'll get it and post it here:  "If the resistance values are properly selected, there will be approx. .6 volts between the base and emitter on any silicon transistor."

So, I guess this means we can measure the resistance, and adjust the resistance to be this value by adding or subtracting resistor values?  That's why I like the pots GM is using because you can tune it exactly where you want it.  Mine are too low of ohms to be any value.  My radio Shack only had 25 ohm pots, not 25 k, just 25.

@ Paul:

Yes, I have been doing that for years but some of the components I need are specialized parts with specific numbers.  I have found that many parts on vcr boards and TVs and computers look like the same part I might need but either have no numbers on them, or some strange number that I am unable to cross check on the internet.  I always salvage stuff when I can, but thanks for the tip.  Are your diode experiments done with germanium ?  Or will any diode work?



I will go back and check the posts as I am sure I am missing some I wanted to reply to.

Bill

[Pirate88179]

Quote from Jeanna:

"Here is a link to the astable multivibrator."


Now there is a product that will sell!  Ha ha.

Bill

[jeanna]

@Bill,
Welcome back 

"If the resistance values are properly selected, there will be approx. .6 volts between the base and emitter on any silicon transistor."

That is the reason you expect to need .6volts just to start up a transistor, and also what you can expect the transistor to be using all the time even when it does nothing, it will just let the energy go through even when off. That is why my led candles with the 47r resistor last 3 weeks on a single charge, whereas the kind with the flicker (= transistor) last 3-5 days.

See, this is SUCH a great thread.

THANK YOU AGAIN AND AGAIN

jeanna

[innovation_station]

it will not fire the neon with the cap in place ....   it will with out the cap ... 


but with the cap in place i light my 7w leds to full brightness  they are 120 vac as well ...   much brighter output  with the cap........ it lights the the 7w led with out the cap but not as bright ....

it runs the curcuitry in the cfl from a cam unit with the cap .... this curcuit requires 120vac .......   this is the point........ 


lower the value to nf......  and raise the volts... as stephen says ...   

ist!

however i WANT TO POWER THE CURCUIT    LOL   I WILL KEEP MY VOLTAGE THE SAME IN THE CAP BUT IT WILL FIRE FASTER ....  WITH  lower value ....