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  1. C

    need a BASIC flip flop, can't find one!

    So to toggle... connect d to q (bar _ ) then use the clock pin to toggle on off (d flip flop)
  2. C

    Using an AAA battery to work a 220v clipper in N. America

    very unusual power supply, 240ac to 1.2v buy a D cell battery and power it from that!
  3. C

    Share clipboard content android/pc

    Take a look at "Craig's Clipboard Share" Runs on Android and Windows and then shares plain text between all devices connected (copy a url on android, paste on windows to notepad or visa versa) copy paste Twitter, facebook, sms between devices.... (remember to delete cliphook from the craigs...
  4. C

    Home made inverter...

    actually. .. this got me thinking, maybe i could exploit the zener effect to block the voltage below 5v etc.... ensuring less wastage as heat? how's that sound? (funny wave form though)
  5. C

    Home made inverter...

    it's not about charging a phone, i'm doing it as a project / learning aid... i've built so many power supplies i thought i'd step it up.. yes, it did occur to me about the losses across the fets but at 50hz... i figured a large enough heatsink should do if i did try it... but, is it worth...
  6. C

    Home made inverter...

    I started out with the intention to build a standard no frills 240ac from 12v ... i have an old toroidal transformer (ac 240 down to 12v/10v - 0 - /12v/10v) 150w from a cheap amplifier simple enough... so i thought maybe i could go one step further and get a sinewave... Now the bit i'm...
  7. C

    Take your guess!

    If that's the case, then it's claims of reuse might be a but exaggerated but they're offering to the Philippines where there is no power (which would imply reusable a one or two use device would not go down well...) maybe it's not that at all.... curious
  8. C

    Take your guess!

    SALt - It's a Social Movement before you go look, it's a startup offering power led lamps even charge a phone? from saltwater (either homemade or directly from sea water) claims to give 8hours runtime ... http://www.salt.ph/ imo, you'd have to have 2 different metals using saltwater as the...
  9. C

    monitor power supply/inverter repair

    under the large capacitor, is that just dirt? or heat damage?
  10. C

    Easy question / confirmation...

    ah, yes of course via pwm to dim it, i'll stick with the resistor :) thanks!
  11. C

    Easy question / confirmation...

    if these ebay pots are 0.1w (see attached) then... 0.1v x 1amp is 0.1watt ? So i should be able to use a 10k pot inplace of the resistor to a 1amp load, or have i gone incredibly stupid after writing so much code lol
  12. C

    i give up.. lm317 + 2n2222

    ok, the original (2am here now, flipping time zones) plan... To avoid using an expensive potentiometer in regulation mode of an lm317, instead use a smaller pot (hence the idea to use a pot to drive a transistor, to allow fine tuning in current regulation. . eg delivering between 0-200ma for...
  13. C

    i give up.. lm317 + 2n2222

    what happened was i got the replies while building the circuit, then when i posted the alerts vanished (and i never scrolled up to look) anyway feeding the voltage to the base never occurred to me, duh, it's like 2 or 3c where my breadboard sits, so i'll build it in the day tomorrow.. thanks again
  14. C

    i give up.. lm317 + 2n2222

    Looks like you guys posted while i was designing my own circuit, this is the first i've seen of these posts, i'll check them out now, thanks!
  15. C

    i give up.. lm317 + 2n2222

    Actually... The transistor option would have been a cheaper substitute, the main goal was to use a cheap pot in conjunction with transistor vs higher rated potentiometer. . i've basically built what i need right here, but it's cheaper to use a 20c transistor and 20c pot rather than using a $3...
  16. C

    i give up.. lm317 + 2n2222

    no... to build a constant current circuit using a transistor in place of a resistor
  17. C

    i give up.. lm317 + 2n2222

    AnalogKid, ahhh ok you filled in the missing part for me, keeping the resistance across the transistor steady in which case the lm317 can be ruled out because i was hoping to use the lm317 to keep that stable voltage drop across it's col/emit ... the challenge was to use something other than...
  18. C

    i give up.. lm317 + 2n2222

    the lm317 adj sits on the emitter .. where i put the non inverting input, the idea being it's output is 1.5v less than the emitter.. or maybe sink the led or use a pnp? i don't know if it can be done due the nature of silicon etc... feel free to try your results would be interesting if...
  19. C

    i give up.. lm317 + 2n2222

    replacing the resistor for a transistor (using the base to vary the resistance between collector/emitter on an npn) my idea was the sense/adj pin on collector to keep 1.5v drop across and it does work somewhat adjusting the pot as a voltage divider i could vary the brightness but after a...
  20. C

    i give up.. lm317 + 2n2222

    I never said it could, i just read somewhere that it could be done, i don't believe it can... your original answer should have been no.
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