Joule Thief

[electricme]

@ bill
Thanks Bill, I will try acitone later on, so you got zapped mate,,,ha ha ha ha ha ha ha ha ha ha ha haww ha haww chuckle.
ohh my sides are akeing from laughing so much 
how are da pinkies bill, do day hurty a little bit? ha ha h ah aaaaah
OK "quiet jim", I better not ware out the friendship

bandaids in the first aid cabinet bill.

I like the BIG capacitor, what a whopper, bet it got quite a punch,,,,,,,,,,,,,,,,,,,,,

I once saw a radio repair bloke accidently bridge out a huge capacitor in a 15watt taxi 2 way transmitter using his wrist.
That knocked him around, he shut up shop for the rest of the day.

Seriously bill, take care mate, watch out for the loose juels, they hurty.

Now its my turn to pull apart a LCD back light unit, time to have FUN FUN FUN

jim

[Pirate88179]

@ Jim:

Thanks.  Well, I have been shocked before.  Once, when I built my first machine shop, the electricians did what they do and passed the inspection. (before we could operate)  then, unknown to me at the time, when they screwed the panel covers back on (they had to be open for the inspection)  they were missing a few screws. (actually machine screws)  So, my electrician used a 5" long drywall screw to hold one of the panels on.  This would have been fine except this extra extra long screw cut through a bunch of wires inside the panel.  So, long story short, I made a big deal about turning on the power of our little machine shop for the first time, a little celebration with the employees, and me, as President got to throw the mains.  Well, we had 4 panels of 400 amps each at 220/three phase.  When I got to panel number two, yes, the one with the wood screw, and threw the main, I got shot across the room!!! ( I had my hand on the panel (ground) for leverage when throwing the big breaker)  The wall around this breaker box was burned, the box was torched, I was lying on the ground some 10 feet away not knowing who I was or where I was, and my entire body was numb.  well, needless to say I hired another electrician to fix the box and to also go over everything the other guy had done, just to be safe.  I am lucky to be here. It had destroyed/melted every breaker in that box, and we actually had to buy another box as it was too distorted.

Long story but, I have been shocked before and, I am sorry to say, probably will be again. (probably when building this circuit.!)

Take care Jim.

[electricme]

@ bill,
sorry I brought back bad memories about being electroquited, yes, you are very lucky to be alive, not to say the extra cost incurred to get another switch panel, it could have gone the other way.
Last week I was charging some nicad cells, they were taking their time and then the charging amps shot way up over 17AMPS.
Before I knew it they were hissing like crasy, so I heaved them outside quick smart, then about a minute later there was a huge bang as one of them exploded. I went outside with some water to cool them off, they sure were hot, you coulda fried eggs on them.
Yep bill, one cannot be too careful, now I charge them when I have a 12v DC bulb in series, if a cell shorts out, then the bulb lights up brightly, instead of the current being sinked into the cells. A fuse would cut the power instantly, but I want an indicator.

OK back to jule thief stuff   
HP w1907 monitor mods.
pulled apart this back lit monitor, what a job that was.
If anyone wants to get into the insides of a HP LED screen, be very careful, you have to pry off the black plastic surround on the FRONT, its clipped together, then it comes apart with lots of breaking plastic sounds, not for the faint hearted.
I broke the 4 mounting plastic screw assembly because I went in the wrong way.

OK, the photos say it all
0123 = HV coils on the main PCB, there are 2 of them, driven by the accompanied components.
0126 = Working screen without the LCD glass pannel and its circuitry, wanted to see if it would work without it, it does.
0127 = Broken LCD screen next to backing light screen.

Hay guys, I don't want to modify this back light pannel, it would be a shame to muck it up, and it lights the whole room with a very bright amount of light, but being said, just mabe there might be a way to drive it with 12v DC. I sent HP techs a message, asking how to keep it running without a VGA signal, it shuts off after a minute.
I think there is a bit of UV light that isnt being filtered by the missing LCD screen, should I cover it with some stickon anti glair that is used on car windows? anyone know?

Yeah, I had fun today, heeps

jim 

[WilbyInebriated]

nice score!
if memory serves, the R G and B inputs are 5V.
edit: my bad it's .7V p-p. pin 5 is listed as TTL ground (monitor self-test) that might do it too.
you should be able run it on 12v like you said, direct to the lamp inverter, unless that's all integrated.

[MrMag]

Jim,

Great idea, thanx. I have a couple of old defective notebooks laying around. Maybe I'll yank the screens off and play around. When I have time that is. Right now just shoveling that damn snow! When is summer here?

Tim