Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Tutorial-Quick DIY 5$ powersupply in 5 minutes...

Joined
Jun 12, 2008
Messages
1,199
Points
48
I used to use this trick power my peltiers while I was still in my overclocking phase. I don't know how many of you are aware of this "mod/trick", but it can be quite helpful when testing a driver and/or laser prior to mounting it inside the host. I thought I would share for those that do not know the trick, hope it is helpful.

****Disclaimer...dealing with electricity can be hazardous, while there is not conceivable way to get hurt with this mod that I can think off, I will not be held responsible for any mishaps***

Equipment needed for the mod:

1x ATX power supply from a PC
Some wire

Optional Equipment:

1xSoldering Iron
1xSwitch


The ATX power supplies found inside PC's are of good use to us laser hobbyists due to the voltage outputs of their given lines. However, turning them on outside a PC requires a very small mod.

4-pin ATX connector:
12v-yellow wire
5v-red wire
GND-black wire


Additional ATX voltage options:
(found on main ATX connector)

3.3v orange wire
-5v white wire*
-12v blue wire*

*has low current handling capabilities, can't remember exact number but in 100ma ranges, also depends on power supply.

ATX Motherboard connector:
Atx_pinout.GIF



The mod is very straight forward and simple. If you look at the diagram above, you will notice a green and a grey cable, the green is PC ON and grey is PWR-OK, it is through this two wires that the motherboard instructs the PS to turn on when you push the power button.

This mod is nothing more than jumping these two wires, and presto you have a very good power supply capable of putting out quite a nice sum of amps through the 12 and 5v lines, the amount depends on the PS you have chosen for this mod, it is always written on a sticker on the side of the PS. I do not mind cable spaghetti and since my PS has a switch in the back I have no need to place a switch between the two wires, therefore it took me 2 minutes to do and if I wish I can just take the cable out and use the ps in a computer. However, one could get really creative and install the PS in a nice box, with a separate switch and make it look very spiffy by adding a gnd terminal and terminals for all the separate voltages, but this is up to you.

There you have it a 5 buck PSU that took 5 minutes to complete. Hope this will be off some use to you. On a side not I think that the trick is pretty straight forward, but if anyone needs a picture just ask.


Thanks
brtaman
 





Joined
Jul 24, 2007
Messages
2,749
Points
0
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

I took an old computer to the tip this evening without thinking about removing the PSU :-/I wish I had read this earlier......... Funny thing is I had spent part of this evening converting an old CB power supply from fixed 13.2v @ 2A into an adjustable by adding an LM317 circuit......

Regards rog8811
 
Joined
Jun 12, 2008
Messages
1,199
Points
48
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

Too bad you threw it away this trick/mod is cool for recycling old computer PSU's :p. Which most people have lying around anyway. On the good side you can get some old 250ish W PSU for dirt cheap anyway and it will probably put out 15-20 amp on the 5v line and 10's of amps on the 12v one.

I also use mine for diode testing in conjunction with a LM317 driver, it is pretty usefull.


brtaman
 

tomcat

0
Joined
Sep 10, 2007
Messages
352
Points
0
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

yeah i use this all the time for fixed voltage supplies i always used to ground both the pwr ok and pwn on to black cables that seemed more stable than eachother i made a old 1kw server supply into a "dirty labby" i/e a psu lab style but not the "perfect voltages" that true lab supplies give :) iv used it to power a TEA laser and railgun and coilgun and a "pennyshrinker" that only managed to blow half my garage up because the shielding i was usin was NOT ballistics proof.....
 
Joined
Jun 12, 2008
Messages
1,199
Points
48
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

Yeah these PSU's are not exactly labby's, but they do a pretty good job supplying power, especially for the money or lack there off :)

Ive been thinking of making myself a coilgun, but I can't find a place to give me all their old disposable cameras, damn digital age, and I am a bit to cheap to actually pay for the caps out of my own pocket, because I know I would go completely overboard...again...

You weren't by any chance filming the pennyshrinker action by any chance, were you?


brtaman
 

tomcat

0
Joined
Sep 10, 2007
Messages
352
Points
0
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

well the camera got hit and was shattered into tiny pieces by a piece of flying molten copper not had a camera since... im just glad i decided to put the trigger switch and me in another room when i fired it up....

the caps i was using actually survived becuase they were in a 8mm steel case under the table where i had my explosive coil set up they were audio grade capacitors froma old amp i had they were 100v caps of unknown farads (i just charged them until they got to 60v) but they were HUGE things almost 3 inch diamater and 6 inch tall electrolytic caps with a thick metal case around the middle and terminals ( one end was just the usual aluminium casing for blowout point


they eventually stopped working and just became 2ohm resistors...
 
Joined
Jun 12, 2008
Messages
1,199
Points
48
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

LOL tomcat, it was a smart decision to put the trigger into another room :D, I imagine the wife was plenty pissed when she heard it go off? ;D Those caps do sound like they can whomp out some joules :D Did you use them on your rail-gun?

Thanks for the link bionic badger I just might make a tesla coil, been thinking about it for a while now, but i keep getting sidetracked...I really like the bottle recycling :)


brtaman
 

rkcstr

0
Joined
Dec 1, 2007
Messages
1,368
Points
0
Re: Tutorial-Quick DIY 5$ powersupply in 5 minutes

If you need some big caps, I have some:

Cornell Dubilier 3700uf 450VDC (quantity: 2)
Mallory 13000uf 40VDC (quantity: 2)
Sprague Powerlytic 25000uf 40VDC (quantity: 1)
Sprague Powerlytic 51000uf 40VDC (quantity: 1)

They're all huge, with the 450VDC ones being about the size of Campbell's Chunky soup cans.
 




Top