Cathode inverter, can I build it myself?

[Mysteriphys]

I'd like to start out by saying, I'm new to you all, but not new to modding, I've had a few projects over the years including stealing Ideas from dell (and parts to make it work, and cutting air vents, and even fun LED work, (I've also done some automotive fiberglassing which is very transferable to case modding ;)

point being, thats why I didn't post in the rookie nook :) hopefully I'm taken seriously, I'm actually working quite hard on the mod that I'm doing, but I am going to take it step by step to make sure it works the way I want it to.

so heres the thing, I want to do a pretty crazy mod, I've got a bunch of parts, and I'm ready to go, 2 things holding me back, I've not got the experience (for the specific mod), and I've not got the knowledge base(for the internal electronics).

so here is what I need to fix first. I have a cathode out of a 10 inch laptop screen that I want to put in the machine just for lighting, I have the origional inverter, but I can't for the life of me find the wiring schematic for it to get the proper voltage and hookup, so I was wondering, since this place looks pretty full of knowledgeable people..

does anyone here know where I can get some instructions on building my own inverter? I've got the basic principle down, as far as formula goes, I ave to have a source voltage (which I've pretty much decided should be the extra 12v rail on my psu since I don't have a fancy pci-e card to use the rail) which the output on it runs approx 300 ma at 20 watts.) I need to make an actual formula that could output the parts I need to get it to the right voltage for the cathode, which from what I've seen by looking around works out to about 600v at around the same amperage.

I could be wrong, anyone with some background will know where I'm bsing :-P but if you get what I mean in a round about way and know how to help please post! any info is appreciated though!

[Bucko]

I'm not sure how you would go about it, but you have to ask yourself, is it worth the mucking around?
Cold Cathodes are cheap enough that you could just go and buy them with inverter and be done with it. I can get two 12" cathodes with inverter and a molex plug on it for under AU$20 at my loacl electronics store.

[calumc]

if i were you id just try hooking up the inverter from the laptop to 12v, thats probably what it is. as for building your own: youve said that you have little experience with electronics so would you really want to be messing about with 600vAC?

[Mysteriphys]

well, honestly when it comes to soldering and such I'm pretty good at that, the part of the electronics I'm not good at is devising the pieces of equipment I'd like to build, from pics I've seen inverters look pretty straight forward as far as the actual construction goes, and I've been looking into home made copper pcb's with pinouts that look pretty good for what I want to do.

[calumc]

have you tried anything with the original inverter?

[Mysteriphys]

ya, I've contacted a few places to try to get the pinout and some possible instructions on connecting it just to get a power signal if I can get that signal I get power to the cathode and I'm good to go.

[Mysteriphys]

http://www.audiofoolz.com/mysteriphys/pict0015.jpg

thats the pinout and I made a little legend for it since the green and red weren't showing up very well, never buy vivitar cams :-P

and actually, most places say that 1,2 are power + 3,4 are power -, but anything I've found has more or less pins than mine, so I don't know which one to use to tell it to operate, i.e. switchable bright on ect


also my reason for not buying anything is that I'm trying to find little ways to do a "look I did this for free!" mod :-p

[dgrmkrp]

Hi, first.. yeah, you are trying something really weird :P Second, I'm surrounded with bits and pieces of electronics right now.. so: post a more detailed and clear image of the board itself: front and bottom. Third, I played with laptop lights so I know they are 12V input and 600V+ output, but it won't kill you (maybe burn you or make your finger numb), cause it is really low amp and the wires can't be very long either.. I would recommend you buy a normal inverter and salvage the light tube itself.. I bet you it will work. Also, even if in principle the inverter might work, I had a not so pleasant surprise of seeing several circuits work at first but die in a mater pf minutes because of some not very good chosen values or components.. So, buy an inverter :) It is easier and not that dangerous.. It can be the cheapest you can find :)

If you wanna figure out the board yourself, than look at where the transistors have wires coming from their legs and where they are going: one wire from each of the 2 transistor should go to the small transformer, one wire should be linked to the ground.. and one to the 12v :) also, you may try powering it, at your own risk, as there is 50% chance it could burn, and measuring with a multimeter if the output is ok.. or seeing if the tube lights up :) happy modding :)

[Mysteriphys]

thanks for the info, now that I think of it, I missed alot of things I already know and I didn't even think about I.e. polarity of the components. Duh on my part for sure :) I'll look again, theres gotta be some kind of "on" switch though because I've tried alot of combo's and I know the inverter and tube are still good because they light up with the laptop I still have in.. well mostly still together :) I'll keep trying maybe I can use the usb as an on function, low voltage ect, might be the key

just tried to take more pics and they're worse, I think the cam is about fried.

[Mysteriphys]

GOT IT!!!!! red pin was "bright-on" :-D I just connect the on to the 5volt source with the +- connected to the 12v side and everything is good to go :-D.

anyother BIG advantage to using this laptop inverter (from massive research) is that alot of the kit inverters fry way too easy, I've seen everything from "my computer was on fire today" to "I hate that burning plastic smell"

the only disadvantage is the size, (they're about twice as long) and they don't come with a cover, so I'll have to man one out of some cd cases or something (wanna show of that ghetto engineering ;)

p.s. I will take pics as soon as I find my battery charger, I just realized my batteries got no juice left, thats why the pic sucked.

[Mysteriphys]

http://www.audiofoolz.com/mysteriphys/pict0012.jpg

hey, here it is, quick and easy, (once I decided to start testing bright-on switches) note: the yellow and red are reversed on the molex due to the original wiring being for a 5v fan, I just swaped them, worked like a charm

and to prove it works :-P

http://www.audiofoolz.com/mysteriphys/pict0001.jpg

woot for free mods!

[Mysteriphys]

server hosting my images is down... dunno why... arg

[Mysteriphys]

pics are back up if anyone wants to look now. ps, I have a cpu fan bezel mod coming up.