Recent content by jwc

MBR viruses are very rare nowadays. Even if you had one, as long as you wipe the whole drive and rewrite the MBR, it'll be gone. You can probably do this from a Windows installation disc, and definitely can do it from any Linux utility by doing this: dd if=/dev/zero of=/dev/sda where sda is...

I wrote up some notes on this. You should include a diode to drop the voltage a bit. Otherwise, you can put extra stress on the driver. Improving Cheap Green Laser Pointers @ JWC.blog As for OP's post, my guess is that you fried the driver. IIRC, the FlexDrive doesn't like voltages that...

My two meters: http://jwcxz.com/projects/lasers/pics/09-09-27_02.jpg The one at the top is a Liconix meter with a photoelectric detector. This meter looks like it was originally used for gassy lasers since it has wavelength selectors for common gas laser wavelengths. I've been meaning to...

Yes, when I noticed the current dropping I assumed that there was an overheating issue. My hand also accidentally brushed up against the IC and I burned myself too, so I knew it was time to find something to start sinking the heat. Interestingly enough, I was able to get that chunk of aluminum...

D{avid,akota}: If you want to see what the crystals in a DPSS laser look like, here are a few shots I took of mine: Crystal Tests and Module Characterization @ JWC.blog More DIY Greenie Progress @ JWC.blog Unlike most lasers, the two crystals in this set are not glued together, so you can see...

MIT OCW is a great tool for learning about all sorts of things. I use it all the time. :) You might also want to look at: 6.097 - Fundamentals of Photonics http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-974Spring-2006/CourseHome/index.htm 8.03 - Physics III (has some...

I have several Tenergy batteries and though I don't have a meter to test the capacity of these batteries, based on my estimates, they are performing roughly correctly. I have used BatteryJunction before. They're just a few states over, so the shipping is extremely fast: BatteryJunction.com...

#laserchat is a channel that many LPF members visit. It has unofficially become the "official channel." LPF's server is only used to serve this website. Several #laserchat members from LPF are server admins of ecnet.

On the multimeter, you should pay attention to the maximum current that you can read with the ammeter. For reference, a 250mW LOC red diode needs about 400-420mA of current through it. The multimeter you linked is a little strange. The website says that it can measure up to 200mA, but on the...

#laserchat @ irc.ecnet.org:6667

I took a tour of my school's Tokamak once. It was especially amazing because it was undergoing renovations and so parts of it had been disassembled. The ITER facility will be pretty amazing if it's ever completed. It will be able to produce more output power than it inputs after starting up...

My pistol coach has three basic safety rules: 1. Always point the gun in a safe direction. 2. Treat the gun as though it was loaded. 3. Keep your finger off the trigger until you are ready to shoot. It certainly seems like these rules also apply to lasers.

Yup. I wonder if the particles being trapped in the case of the electrical tape are from the adhesive. It appears that my video has been posted on Reddit, so whichever one of you did that: thanks! :)

It's TEM00 (zero zero) Transverse mode - Wikipedia, the free encyclopedia

That's one possibility; it certainly seems plausible. I've heard that very soft plastic is also effective, so I would imagine that pieces of the felt are just breaking off. You could see by taking some black felt and trying the same way. If it doesn't release particles as well, then it's...