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 a Radioshack regulated power supply+LD

Joined
Aug 26, 2007
Messages
334
Points
0
I was wondering If I could use a radioshack power supply to make a safe working LD.

I don't want to build a regulating circuit so I was wondering if I could use it instead.

I have a 12volt dc power supply from radio shackand it reads exactly 12volts.

so can I use a 3 volt supply with a certain amound of ma for a LD?

if so, how many ma?
 





Joined
Feb 1, 2007
Messages
810
Points
0
Re: Can I use a Radioshack regulated power supply+

That would depend on how stable the supply delivers the voltage, and really you will need a current limiter.

This is what I use, I dial in the voltage, and set the current limiter to the max amps, I wish to drive. It is extremely precise, and therefore quite expensive.

Jase
 

Attachments

  • P1010071.JPG
    P1010071.JPG
    851.4 KB · Views: 961
Joined
Aug 26, 2007
Messages
334
Points
0
Re: Can I use a Radioshack regulated power supply+

thanks. The radioshack power supplies are VERY precise.

MMM, I might sound like a retard, but how do you check current on a multimeter?
I've never had to check current so I don't know.
 
Joined
Feb 1, 2007
Messages
810
Points
0
Re: Can I use a Radioshack regulated power supply+

Phazonx said:
thanks. The radioshack power supplies are VERY precise.

MMM, I might sound like a retard, but how do you check current on a multimeter?
I've never had to check current so I don't know.
very easily Phaz.

1/ Voltage or potential difference is measured in Parallel across the +ve and -ve terminals of your power source Red probe on the + and black probe on the -

2/ Current or amps is a measurement of flow down a conductor and measurement must be taken in series. Put simply, you break a circuit on its positive side (usually) and route the power through the red and black probes, with the red facing the +ve side of your power source. This pic will show you better.

Jase
 

Attachments

  • current.gif
    current.gif
    3.3 KB · Views: 349

Daedal

0
Joined
May 23, 2007
Messages
2,277
Points
0
Re: Can I use a Radioshack regulated power supply+

Tallaxo, what'd you do to that poor knob? :eek:

Another case of the 'PS gone bad' + some spanking maybe? ::) J/K

--DDL
 

Daedal

0
Joined
May 23, 2007
Messages
2,277
Points
0
Re: Can I use a Radioshack regulated power supply+

Phazonx said:
thanks. The radioshack power supplies are VERY precise.

MMM, I might sound like a retard, but how do you check current on a multimeter?
I've never had to check current so I don't know.

Phazonx, I think there should be a knob that you can turn around... one side should list the V, the other should say A or I... these are for Amps or Current... both of which are the same ;)

As about the RS PS... they are probably precise on voltage... but that's no good for a LD. You need precise current :-/ They like that specific voltage, but they NEED that specific current :p

GL;
DDL
 
Joined
Feb 1, 2007
Messages
810
Points
0
Re: Can I use a Radioshack regulated power supply+

Daedal said:
Tallaxo, what'd you do to that poor knob? :eek:

Another case of the 'PS gone bad' + some spanking maybe? ::) J/K

--DDL
It still turns with a screwdriver ;) Kids and daddy's stuff, still seem to find a contest of interest. Kids break it, I cry.

Haha.

Jase
 

Gazoo

0
Joined
Jun 9, 2007
Messages
3,206
Points
38
Re: Can I use a Radioshack regulated power supply+

Phazonx said:
thanks. The radioshack power supplies are VERY precise.

Personally I like the idea of turning a decent computer power supply, into a bench power supply, although I have not done so. I don't believe it would be much more expensive than the ps RS sells, and I believe it would be a heck of a lot more accurate. Plus with a computer supply, you have different voltages to play with, and ample current. Of course current would still need to be regulated going to the diode....but this is very easy using Daedal's circuit, and you could even use a higher current version of the LM317T if you had other applications that called for it. Following is a guide on how to do it:

http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply
 
Joined
Aug 26, 2007
Messages
334
Points
0
Re: Can I use a Radioshack regulated power supply+

hey daedal.

I built your circuit you said to make.

you know the one for the LD

well, I had every thing except a 100 ohm pot.

I only had a 2k ohm pot.

will it still work?
 

Daedal

0
Joined
May 23, 2007
Messages
2,277
Points
0
Re: Can I use a Radioshack regulated power supply+

Nope... sorry. It simply won't be accurate enough at the bottom end which is where we need it. Try getting a smaller one. 25-ohm, 50-ohm... even a 10-ohm would be fine if you're using it with one of SenKat's diodes.

Other option is to use a 5-ohm resistor and no pot :) This will give you 250mA current supply ;)

GL;
DDL
 




Top