Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

Buy Site Supporter Role (remove some ads) | LPF Donations

Links below open in new window

FrozenGate by Avery

Sony 20x burners $24 at Newegg

ok, before I start working on the schematics for this thing, how much current should I run it at? I don't want to spend 25 dollars every week to replace a diode, so that means I won't be pushing this diode to its max, BUT I still want it to be fairly powerful. So the real question is, how much current should I run this at to keep it at, at least 200mW while having it last a long time? and keep in mind that I will be using a glass lens on the AixiZ module which will be heatsinked by jayrob's heatsink. and yes, I plan on using an MXDL for a host.

and now that I mentioned all of that, does anybody see a problem with any of that?

thanks! ;D
 





I suggest you start running it at 350mA. At that current and with the glass lens, it'll be past 200mW, jayrob is running his open can at 420mA and he's getting close to 300mW with the glass lens. So just run it at 350mA, if everything looks ok then turn the current up more, it's you choice.
 
if your using jayrob's heatsink, you are fine at 420mA.

I ran mine for 4-6 mins at a time, it didnt even feel warm with the heatsink. It also didnt seem to drop in power. these open cans can sure take quite a wippin, theyve been pushed to over 500mA! you will be fine at 420mA, as it is the "sweet spot", like 250mA is for senkat diodes.

with the heatsink, you will have long life at 420mA. remember, eith the jayrob heatsink, you technically have that block of aluminum, plus the whole flashlight as a heatsink.

BE SURE to use a DDL driver regardless of mA, because if you dont isolate the diode from the flashlight while using a DX AMC driver, you will be running the diode straight off the batteries, and you will totally bypass the driver. the AMC's also require up to 4.5 v in, which can be a pain in a 6v flashlight.

the perfect, long life, high power, and easy setup is:

Glass aixiz lens: $6
aixiz module: $6
open can: $23
MXDL: $12
Jayrob heatsink: $22
DDL driver: ~ $5
3.6v CR123 Rechargables: $5

Grand Total: $79
give or take a buck

use the 3ohm resistor that is already in the MXDL, solder it to the LM317T, and solder the 1N400x + Cap directly onto the diode.

screw it all in and you will have along livin kik ass ~290mW laser!

with the jayrob heatsinks, you got a lot of options regarding duy cycles and what mA = stable, and long livin output.

IMO, the above is the perfect setup

its also easy, I set mine up in an hour and a half.

regards,

amk
 
Amk, I know that 420mA has been mentioned to be the sweet spot, but I think it's too early to tell, even if the diode doesn't feel warm with the heatsink, it might die at any time, you know how tricky LDs can be, plus they're not all the same, I mean look at Gazoo's "freak diode" 400mW :o I think we should wait a little bit longer before coming to conclusions IMO. :)
 
chido said:
Amk, I know that 420mA has been mentioned to be the sweet spot, but I think it's too early to tell, even if the diode doesn't feel warm with the heatsink, it might die at any time, you know how tricky LDs can be, plus they're not all the same, I mean look at Gazoo's "freak diode" 400mW :o I think we should wait a little bit longer before coming to conclusions IMO. :)
Click to expand...


then again, 420mA is the sweet spot. its also safe. look at the graph Dr. Lava made recently. the open can starts to un stabilize at about 500mA. 420mA is not even in the curve, its in the uphill slope. so, we are running it at a safe mA AND getting good output.

regards,

amk
 
Ok amk, it's just a thought I had since the open cans haven't been used for too long. Then again I don't have my open can yet, so I think I should shut up now. ;D
 
Ok, i've been searching for a while now, but i can't find Mike's graph for the open cans..

I found all the other graphs except for this one. Anyone know where it is?
 
IgorT said:
[quote author=TheMonk link=1202158967/90#103 date=1203443938]Look here :D
Click to expand...

Thanks, Monk!

I think i saw it, but i mistook it for something else, because it was in another thread...[/quote]


**echoes** 420 is the way to go...
 
alright thanks guys!

I have most of Daedal's circuit. The only thing I have to change out is the resistor I think. As for the LM317, is it necessary? because the voltage supplied by a CR123 is only 3.6 volts or something, which isn't even 5(which is what the LM317 limits the voltage to I think). I need some help with this lol. But I'll just see how powerful this thing really is to decide what amount of mA to run it at.

oh wait, I don't have any parts for the circuit LOL. I just remembered I am using that driver for the blu-ray I'm selling my dad. I'm getting 70 dollars from that, which is the money I'm using to pay for all this!!

but I'm so excited because this will be the first high powered laser I have owned. or seen. It will even beat the power of my friend's x-105 ;D :D 8-)

and another thing lol, can somebody recommend a potentiometer for me? the ones that came with the daedal circuits I ordered were MESSED UP!! they would provide a ton of resistance, and I would turn it alot, and it would barely change. then it would jump to basically NO resistance at all!! basically, the mA would read pretty much below 15 for a long time, and then it would quickly go up to 30, and then it would(no lie) jump straight to 120mA!!! this experience has left me with almost no knowledge of pots and how they work. can somebody explain this and recommend a pot to use?
 
dont use a potentionmeter, its not needed.

the one thing that is not needed is the potentiometer. you DO need the LM317T, and the red run off of 3v, NOT 5 like the blu's

the 3.6 + the spke on the battery will kill the diode without the LM, remember, the whole point of that circuit is the current regulation of the LM317T. heck, you could do with just the LM317T and a resistor, but its not recomended.

regards,

amk
 
Abray said:
alright thanks guys!

I have most of Daedal's circuit.
Click to expand...

Good, then follow the calculations and you won't have any problems:

The LM317 is no mystery and very easy to work with. The following calculations always apply since it uses 1.25 volts for its reference voltage.

To calculate the resistor needed for a given current, take 1.25 and divide it by the current. So say you want to drive a SenKat diode with 250 ma's. 1.25 divided by .250 = a 5 ohm resistor.

Another way you could do this is to take 1.25 and divide it by the resistance. 1.25 divided by 5 = .250.

Next you will want to calculate the wattage of the resister needed. We know 1/2 watt resistors are common for use with the regulator. But to figure it out, simply take the 1.25 and multiply it times the current. 1.25 times .250 =.3125 watts.

The rule of thumb for the voltage going into the regulator is it should be 3 volts more than the voltage going to the diode. A SenKat diode running at 250ma's will have about 3 volts across it. Therefore a minimum if 6 volts is needed.
I recommend 6 nimh batteries or 2 RCR123's for use with Daedal's driver.

Some of the MXDL's have been coming with 2.4 ohm resistors. If you need 3 ohm resistors I think here is a good place to get them from.

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=003-3
 
Abray said:
I have most of Daedal's circuit. The only thing I have to change out is the resistor I think. As for the LM317, is it necessary? because the voltage supplied by a CR123 is only 3.6 volts or something, which isn't even 5(which is what the LM317 limits the voltage to I think). I need some help with this lol. But I'll just see how powerful this thing really is to decide what amount of mA to run it at.
Click to expand...

The LM317 doesn't limit the voltage to 5V.. Maybe you were taking a reading without a load?

In current regulation mode it needs a load to regulate the current.. With a LD it will adjust the voltage all the time, to keep the current constant, even when the LD heats up. This will be around 2.85 at 300mA, depending on the LD.. If you connected the LD directly to the battery, you would kill it pretty soon. The current from a full LiPo would be much too high, and since the current wouldn't be regulated, it would actually increase, as the LD would heat up..


Use two Li-Po rechargable 3.6V cells with the LM317. This way, you will get 8.4V when both are full and 6V when they are empty, which is perfect for this circuit, as it needs 6V or more to regulate the current.


Follow the circuit exactly, recheck all the connections, and use calculations Gazoo posted above to figure out the best resistor.
 
IgorT said:
[quote author=Abray link=1202158967/105#106 date=1203476557]I have most of Daedal's circuit. The only thing I have to change out is the resistor I think. As for the LM317, is it necessary? because the voltage supplied by a CR123 is only 3.6 volts or something, which isn't even 5(which is what the LM317 limits the voltage to I think). I need some help with this lol. But I'll just see how powerful this thing really is to decide what amount of mA to run it at.
Click to expand...

The LM317 doesn't limit the voltage to 5V.. Maybe you were taking a reading without a load?

In current regulation mode it needs a load to regulate the current.. With a LD it will adjust the voltage all the time, to keep the current constant, even when the LD heats up. This will be around 2.85 at 300mA, depending on the LD.. If you connected the LD directly to the battery, you would kill it pretty soon. The current from a full LiPo would be much too high, and since the current wouldn't be regulated, it would actually increase, as the LD would heat up..


Use two Li-Po rechargable 3.6V cells with the LM317. This way, you will get 8.4V when both are full and 6V when they are empty, which is perfect for this circuit, as it needs 6V or more to regulate the current.


Follow the circuit exactly, recheck all the connections, and use calculations Gazoo posted above to figure out the best resistor.[/quote]


2x 3.6 batteries = 7.2 volts :-?
 
OH I didn't know the MXDL ran off of 2 batteries. sorry guys :(

but thanks for all the help on the circuit!

so If I wanted to run the diode at 420 mA, then I would want a 2.97 resistor... lets just go with 3!
Another question. I've heard of the wattage of a resistor about twice. Can somebody explain that too?

Alex
 
You must log in or register to reply here.





Back
Top