Some idiot reversed polarity on my PGL--III-C.

[Canuke]

Unfortunately, it was me Got the magic smoke and all... I know that smell anywhere.

So: is this fixable by a hobbyist, or are DPSS units too precise? Can parts be had?

Spec info: this is a 3.7V single cell lithium unit, green DPSS =~ 250mW or so.

 

[dr-ebert]

Depends on what exactly got killed. I think it's a good chance only the driver died, not the pump diode (it should be able to withstand that much reverse polarity unless you've got a boost driver inside - having an inductance would be a telltale - but probably not even then); the crystals don't care. I'd try to replace it with a drlava FlexDriver.

 

[Flaminpyro]

With out knowing the spefic circuit in the driver it would be hard to say from here if it can be repaired. I vote with DOC-E replace the driver board with a flex drive my flex drives should be here any day now in case you don't have one or know how to put it in PM me maby I can help you.

Peace All Pyro...

 

[HIMNL9]

Only, remember that IR diodes have positive cases, and in most of the pointers, diode case is also the positive power input for the driver (where instead flexdrive have a negative in common) ..... avoid short circuits

 

[Krutz]

exactly! a flexdrive simply wont work with (regular) green lasers. i use two AMC7135 chips from a dealextreme board to power my 100mw o-like module with 600mA. just the two chips, nothing else. works fine so far. cheap, and definitely enough for a quick check if the diode still works.
of course you dont know what exact current the original driver provided.. but you can (with more than just the bare chips) slowly turn the current up and measure the output..

manuel

 

[Canuke]

So it may be just the driver, eh? That would be nice.

I should note that the battery was freshly charged (4.2V), don't know if that might provide the extra bit to bork the diode.

HIMNL9: that sounds like the reason why these things are positive to the tail

I have a power supply with current limiting which I can use for testing, so I'll have to try digging into this thing when I next get home. Just swapping in a driver would be niiice.

thanks guys! I'll check back in with results in about a week.

 

[Canuke]

Um, taking a look at this thing now... does anyone have experience with disassembling these? It looks pretty tight. google yielded nothing.

 

[Krutz]

cant help you with opening this up, sorry. perhaps pressed, perhaps screwed, possibly glued. without knowing what you do, you will easily damage the host, at least..
I would be careful with a regular (stabilized and limited) powersupply. if there are spikes, which you wont easily notice, it will fry your diode. at least try a cheap diode first, get a dvd drive (not necessarily a burner), extract the red diode, see if you can drive it with the powersupply.

of course you can also use a lm317 driver, at least for testing. it just needs a much higher voltage, at least two cells, maybe three (dont remember, never used this one). much info about this: http://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339.html

when you found your laser to work with the lm317 driver, you can as well fine-tune it to your desired output, note the current, and replace the driver with the amc7135 ones so you only need one single battery. more batteries wouldnt help, actually. so if you *want* more than one battery, tell us!

if you want to use the AMC7135, better order now, it takes up to 2 weeks for dealextreme to deliver to your door..

manuel

 

[Canuke]

Well, I couldn't determine any way to open this thing up from the back, so I tried the front. Three set screws for the shutter, followed by a lens mount and the laser assembly held behind a retaining ring threaded inside the heatsink. IR filter glued to the front of the laser aperture (quite loosely, I might add... if you don't want IR, don't drop one of these).

The lens slug and retaiing ring each have two small holes that accept the tool used for retaining rings. The lens assembly was easy to remove... but the retaining rung, coming up through the same threads as held the lens slug, tightened up right at the exit and is now stuck there (some anodizing in the threads? it didn't cause issues with the lens slug)... I ended up snapping one of the tips off my retaining ring tool.

I need to figure out how to get it the rest of the way out... currently considering some dremel work. The laser assembly is loose and mobile in the tube now, and I've got an inch clearance between it and the stuck ring, so I can insert something to protect it should I start cutting.

 

[Canuke]

Krutz: I've safely run a PHR with my particular PSU; it lets me cap the current at a specified value, so I set it to something well below maximum spec for testing, just enough to see some light, and with filter caps. Nevertheless, I should get some LM317's as you suggest anyway.

Thanks for the headsup on a new driver. I hope to finish extraction and testing this weekend.