300mw LOC Lab build w/picts

This is a labby style red build I decided to throw together yesterday. I don't have many picts as of now, but it shouldn't take many of them to get the idea across. I suspect I'm getting ~300mw of 660nm light.

Components include:
LPC-815 LOC diode
DDL driver set at ~416mA
Meredith Glass lens mod by Jayrob
2X DH DJR Black anodized heatsinks
Toggle Switch
Blinking LED indicator light
Radioshack project box


A Few of the internal components, diode module not shown. Since I'm halfway normal, I don't happen to have any 3 ohm, half watt resistors lying around, so I used a pot and set it at 3 ohms, and hot glued the knob in place.


Front


Rear view, showing the toggle switch, removable power connector, and Red blinking LED indicator light on top.













A few beam shots- not bad for a $100 kodak eh?









The Meredith lens mod by Jayrob makes the beam very tight for very long distances. The focusing is a bit touchy for long distance burning, but its still achievable. The module for the laser gets warm after about 2 mins, but it only takes about 1 min of power off for it to cool down again. The overall build isn't very heavy. The detachable power connector is in place for better portability. I also plan on making a 12V flashlight battery case so I can take the build outside for some star pointing, firework lighting, and uh... bug frying?

What the world is the RCA Audio connector used for as seen in first picture ?

Nice job Meatball, looks like it burns pretty well.

Jon

wesdaman14 said:

What the world is the RCA Audio connector used for as seen in first picture ?

Click to expand...

That's just the connector I used for the LD output from the driver. It so I can disconnect the LD from the circuit without having to cut wires, in case I ever have to change out diodes. Not very typical I know, but it works.

Very nice project box build! :drool: My box build with LPC-815 will be almost ready, just need the diode from mail and its ready. It will look kinda same as yours.

I also use a variable AC/DC power supply set 7,5V, for burning inside, and for portability 2x 9v batteries. Also i have DDL driver set at 420mA (?)

I also thought of adding led indicator light, two coloured, it would show is it on from ac/dc wall adaptor or from batteries.

But, very nice build. Where did you get that LM-317T heatsink thingy? Would be VERY useful

MAPESA said:

Very nice project box build! :drool: My box build with LPC-815 will be almost ready, just need the diode from mail and its ready. It will look kinda same as yours.

I also use a variable AC/DC power supply set 7,5V, for burning inside, and for portability 2x 9v batteries. Also i have DDL driver set at 420mA (?)

I also thought of adding led indicator light, two coloured, it would show is it on from ac/dc wall adaptor or from batteries.

But, very nice build. Where did you get that LM-317T heatsink thingy? Would be VERY useful

Click to expand...

Thanks!

This way a very simple, easy to make build. Mainly since all the parts except for the LD and LD heatsink were parts from radioshack.

I found that mounting the LD module was very easy by simply pinching the enclosure wall with the two identical heatsinks.

420mA is golden. What battery holder might you use for those 9v cells? I was thinking a taking a 12V UPS backup battery (lead acid), and hauling that around in a separate enclosure. I could use a UPS to charge it.. As for using two separate power supplies, I might recommend doing what I did by mounting a panel- mount connector in the rear, so the two supplies can be easily switched.

The heatsink for the IC is actually two of them sandwiched together back to back. I think I found them inside an old audio receiver one time and just pulled them. I do believe radioshack has a couple..

TO-220/TO-202 Aluminum Heat Sink - RadioShack.com

TO-220 Heat Sink - RadioShack.com

Even with my two heatsinks, the overall IC setup still gets very warm.

lookin good! toast them bugs man!

Too bad Radioshack wont ship to Finland. Last night i just soldered a washer to the LM317T. It didnt break or anything, working good. (lm317)
I got no heatsink options for the driver, so i guessed washer is better than nothing.

For the batteries, you mean an actual holder, keeping them in place inside the box or a connector? Well, i got 2x 9v's taped together (kinda one big 9v), and it just cant move cause my wire/hotglue mess inside the box

I use a very standard snap-on connector, and i have soldered another similar connector to its wires, so it has only 2 wires out but can hold 2 batts in parallel.

I just realised i have absolutely NOT any kind of heatsink for the aizix module w/LPC. My friend's dad could hopefully make a simple one.

Meatball said:

That's just the connector I used for the LD output from the driver. It so I can disconnect the LD from the circuit without having to cut wires, in case I ever have to change out diodes. Not very typical I know, but it works.

Click to expand...

I bet you get a much better laser beam with a much more expencive audio cable - maybe you should go for a fully balanced XLR connector instead. I'm sure the beam vill be more hi-fi, with lower distortion, and smoother beam

Vidar (Not only a laser-nerd, but also an audio-nerd - next to RC plane-nerd and perpetuumobile-nerd)

I don't think this is a good approach... at least not using a plastic case. At these current levels those diodes require cooling, and lots of it. The very least you should do in a setup like this one is use a metal case and ensure good thermal contact to it.

Howdy Meatball :yh: nice build realy clean, I love the pic with the smoke comming off the tape !!!

peace Pyro...

Lol Low-Q. Thanks FlaminPyro!

Benm: I do see what you mean. I have been careful with my duty cycles so far, and haven't seen any heat problems. BUT I do plan to stick a 12V fan on top of the case with some nice holes punched in the side. My DDL driver even with its heatsink is getting way hotter than the LD. Do you suspect that a fan blowing air through the enclosure will keep it cooler than a fan that sucks air through the enclosure?

Heat rises so you are better off having the fan suck the air out if mounted in the top. Either way a small fan will help a ton. You have a great start. Eventually you might want to think about powering it with a LiPo battery, or a LifePo4. You could get everything to fit in the box. I would not use 9 volt batteries...they sag and don't last long. If you want to keep powering it externally, then a small 12 volt gell cell battery would probably be cheapest for portability.

Meatball said:

Lol Low-Q. Thanks FlaminPyro!

Benm: I do see what you mean. I have been careful with my duty cycles so far, and haven't seen any heat problems. BUT I do plan to stick a 12V fan on top of the case with some nice holes punched in the side. My DDL driver even with its heatsink is getting way hotter than the LD. Do you suspect that a fan blowing air through the enclosure will keep it cooler than a fan that sucks air through the enclosure?

Click to expand...

Dont worry about the LM317 getting hot - it can operate to temperatures over 100C on its tab, and has automatic thermal shutdown if pushed over.

The LD is another story entirely and should be kept close to room temp for best performance and long life. It might be possible to mount a star-shaped heatsink (intended for transistors) around it on the outside of the case. Drill some holes behind it in the case, and also at the opposite end of the case. Place a fan blowing out at the far side from the diode.

But in all honestly, this fan-based cooling approach is only required because of the plastic case. If you used a metal one this size it would do the cooling job passively.

I see I see.. well I think you've convinced me to put a fan on top. I have several 3" fans lying around and a single 1" fan I could use. One problem I might be running into is finding the best way to cut a clean looking hole for the fan to sit on top of. A one inch circular one shouldn't be a huge problem, most spade bits on drills can easily get that size. But that would limit me to using the 1" fan. If I wanted to use the 3" fan for better cooling, then I would need a way to cut a ~3" hole on top of a 3" wide enclosure. :/

As far as air intakes go, would they best be drilled into either side of the enclosure next to the laser module, or in the rear?

Thanks

@gazoo - only reason I use 9v's is that they were completely free to me and i have enough of them. I definitely would use some lithium battery, but i didn't want to buy some lith rechargeables and charger for them when i can use free batteries and change them anytime i want - i have enough of em