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

can i use this for a labby?

jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
hey guys i just found a transformer that is AC to DC ok so input is just normal 120v and the output is 12v (300ma) i wanted to use this for an lpc-826 diode, but my question is how can i make this work with the dc power, can i get modules with DC female at the end? or do i strip the end off and use those wires i have a pic but its terrible quality from webcam (my phone could do a lot better lol :)) but it shouldnt really be needed as i provided info but i have it with me now if anyone has more questions about it. oh and BTW i randomly found it it says barbie on it so i guess it had something to do wit it :D dont worry its not pink with flowers just white ;)

EDIT-pics wont upload :eek: i can redo it later but im not going to post any unless if you guys need/want me too :thanks:, Justin
 
Last edited:





jeffreythe00

jeffreythe00

0
Joined
Jan 13, 2010
Messages
2,516
Points
63
So what you have is a AC to DC converter. (Doesn't matter if it says barbie does it?)

So you have 12V DC @ 300mA.

What you NEED is a driver that will run the diode at a constant current. I don't know of any drivers capable of running a LPC @ 12V so you'd have to wait for someone else to reply there.

However you can just use the bare wires you have if you want OR you can get a male/female adapter. Your choice really. One thing you have to check is the polarity of that transformer (which wire is + and which one is -).
 
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
THIS is what I used for my labby(the first one on the list, product code BE227). It has different tips so I just picked one and tested the polarity using an LED. It allows you to pick the output voltage which helps A TON with heat issues for your driver.

I found mine at Fry's Electronics for 9 bucks i think? It works VERY well.

Hope that helps,
Isaac
 
Last edited:
jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
jeffreythe00 said:
So what you have is a AC to DC converter. (Doesn't matter if it says barbie does it?)

So you have 12V DC @ 300mA.

What you NEED is a driver that will run the diode at a constant current. I don't know of any drivers capable of running a LPC @ 12V so you'd have to wait for someone else to reply there.

However you can just use the bare wires you have if you want OR you can get a male/female adapter. Your choice really. One thing you have to check is the polarity of that transformer (which wire is + and which one is -).
Click to expand...

This is at a constant current isn't it? and it says the polarity on the label but i don't exactly know what it means, so i will post a pic :)
:thanks:

wannaburnstuff said:
THIS is what I used for my labby(the first one on the list, product code BE227). It has different tips so I just picked one and tested the polarity using an LED. It allows you to pick the output voltage which helps A TON with heat issues for your driver.

I found mine at Fry's Electronics for 9 bucks i think? It works VERY well.

Hope that helps,
Isaac
Click to expand...

Thank you, its nice to have someone that did a similar build i want to do ;) and as in tips you mean wires after you cut off the male DC end right?



And just to make sure i am correct whats the min. voltage or recommended volt. for an lpc-826?
:beer: Justin (and o yea thanks for the quick replies, you guys rock! :D)
 
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
I used the 4.5V setting. As for tips I mean the adaptor tips that are included. One of them is a standard 9V connector, so instead of chopping the wires up I connected the 9V connector to another 9V connector that had leads(the kind you can get in the battery section of radioshack). You might be able to see the wiring I did in the Thread linked in my signature under "DIY 405nm PHR-805T Lab Style Laser(125mA)". Just click on the "Review" part.
 
jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
Alright thanks. i will check that out. (another quick reply lol :D)

EDIT-checked out your review :) looks like you had the DC male that came w/ your transformer go into a female DC which then had leads to connect to the diode? i also see you have a DDL driver why is that needed the transformers current isnt constant?
i had this typed for about a half an hour and forgot to post it :yh:
 
Last edited:
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
Output on mine is 500mA max...a bit too much for the PHR I put in....and by a bit i mean a lot....

At any rate, I feel comfortable with a driver, since I know how it works and I built it. I have no clue what is inside this transformer or why they quote the numbers they do. Better safe than sorry IMO.
 
jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
Cyparagon said:
The 300mA rating is the max current it is rated for. It is not constant current. It probably isn't constant voltage either - just rectified filtered AC.
Click to expand...

ahh that clears it up thanks :) and the voltage seems like it wouldnt be much of a problem as long as its not too changing that much


So basically i could go with wannaburnstuff's advice and look for one of those or just deal w/ exess heat about how bad is 7-8 volts extra heat wise

And it seems my transformer wouldnt be too bad as it is rated 300ma and that isnt at the max current for diode so i dont think i could damage it technically, just sometimes it will be higher or lower than other times.
Maybe im wrong i mean i am kind of a noob but know more compared to others i think. besides its a $20 (actually less) diode
 
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
1. 7-8 Volts will be a LOT of extra heat, especially if you are going straight to the diode. Runtimes would be extremely short.
2. I would recommend going ahead and making a driver for it. Just buy an LM317 Voltage regulator and solder two 10 ohm resistors in parallel across the Adjust and V-out pins. The V-out goes to one of the pins on your diode and the V-in goes to your battery/switch/other wiring stuff.
 
jeffreythe00

jeffreythe00

0
Joined
Jan 13, 2010
Messages
2,516
Points
63
You can't give the diode 12V. You would destroy the diode before you even see the red light.

If you REALLY insist on going this route I'd suggest using a cellphone charger which outputs around 5V DC at anywhere around a few hundred mA to 1A and picking up a driver for a few $ on here. There are a few really inexpensive options. I'd then use a capacitor to smooth the current. That's about the most DIY you can go about this other than using a lm317.

Hell. I'll build you a lm317 and send it to you for the price of shipping if you want or I can just send you the IC and you can build one yourself.
 
Last edited:
jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
i do have a small heat sink i could use but i should still probably find something like you have to do a build with this lpc maybe i could use the barbie transformer a different time if i make a build that can use a buck driver (like soj06 or m140)

Hell. I'll build you a lm317 and send it to you for the price of shipping if you want or I can just send you the IC and you can build one yourself.
Click to expand...
:eek: maybe a pic (not a schematic) would be enough but :thanks: if i do fail that much i might take you up on that :) but i dont think its too hard.
i know how to calculate what to use and everything but i probably just dont have enough faith in myself :angel:

here is they crappy little heatsink that i bought a while ago that sucks, but i guess could work w/ an lpc or phr
imgres
 
Last edited:
jwwilson23

jwwilson23

0
Joined
Oct 5, 2012
Messages
99
Points
8
Well i would probably rather just go with a fixed resistor or maybe add a pot in after i add in maybe half of what i need in fixed and that 1n5 diode or whatever isn't that fir reverse polarity? And capacitor isn't exactly needed but good. t can also be bad if u forget to discharge it in between batt changes i believe.
Sorry for my grammar all the side i switched over to mobile, my wife acting up

EDIT- WIFI not wife lol :crackup:
 
Last edited:
IsaacT

IsaacT

0
Joined
Aug 25, 2010
Messages
5,947
Points
83
All I ever use for an LM317 driver is:

LM317 Voltage Regulator
Resistor(s)
Wire
Heatsink

No extra features but for a cheapie build who needs 'em?
 
D

danielone

0
Joined
Oct 25, 2012
Messages
45
Points
0
I think you can switch a resistor before the driver so running at 3V how much mA need your driver ?
 
You must log in or register to reply here.




Top