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By sbremner
Hello all, I'm a total, or almost total newbie. I want to build a small box, like 4 x 4 x 2 or so, which will hold two line laser modules, 2 toggle switches to turn them off and on, and have it run on a 9v battery. I will also need a regulator, like an LM317 adjustable, but that's where my lack of knowledge keeps me from making any purchases. I've tried searching, but it's really just going down one rabbit hole after another for me. Could anyone list the parts I might need, including one of those boards for plugging the components into? I have built a 200w LED exposure lamp for the printing industry, which was easy enough with the correct COB LED and driver, and it works, so I was hoping I could get some help as most of what I read is over my head, but with a little direction I'd be fine. Thanks in advance, and if I'm a PITA, I apologize. I'm not looking to become a techie, or even a hobbyist, I just hate paying 50 times more for a pre-made product, when I know it's really inexpensive.

Hi Steve.

You're probably only going to need a few resistors, a LM317 and a small board to mount them on but it's hard to say exactly what you will need without knowing what voltage your lasers require, and how much current each one consumes.

If the voltage and current requirements are low, the calculator found on this page should show you how everything goes together and you can calculate what resistors you need. For example, if you're needing 3 volts, a 270 and 390 ohm resistor along with a LM317 would do the trick.
I'm not sure on how to to the math on for the resistors with 2 LED's; it's likely that both would be on at the same time. I guess that's where I need the help, though I am starting to grasp the concept a little better. I'll look through the stores for the other parts, which will be educational for me, I'm sure. I'll get back tomorrow.