leadlight modding advice needed

[bootleg2go]

I've modded my glp-110 by doing both the pot adjust and diode/mirror adjust. I also tried shorting the 332 resistor, but that didn't really do anything as far as I can tell. I did get a little boost by increasing the 103(10k) resistor above the pot to 20k. I've managed to get quite a decent increase in output as measured using the led DVM method. It shows the ouput to be about 25-27mw. Another glp-100 a friend bought, I modded the same way, but only can manage about 10mw...not bad as I've doubled the output.
The only problem is that on both units, after 10-15 seconds of continuous use, the output starts dropping on each on. The 10mw unit will drop to 5-6mw and the 25mw unit will drop to around 10-12mw. In each case the output drops by 50% or more. Does anyone have any idea what I can do to get them more stable over the course of 1-2 minutes of use? Does everyone who has modded their 110 have this same output drop as they start to warm up? To tell the truth, I'm not even sure they are really getting hot at all as it is a very short time and it doesn't feel warm at all to the touch. One more piece of info, both unit draw about 225-230ma of current from the battery.

Jack

 

[Spec]

Thats heat.

The emitter of the diode is shifting frequency as it heats.

Its ability to produce 808nM will diminish way before you notice it getting "hot".

From what I have noticed in the past certain manufacturers use an 805-806nM diode so it still produces green right up to the point it dies from thermal shock.

If you really want stability, your not going to get it in a pointer short of adding exotic non portable heat pumps. Sorry.

As far at the "time elapsed" not seeming like its long enough for it to heat up, concider this: I have a 1 watt 808 diode here that would die in about 15 seconds if it wasnt properly heatsinked to a peltier element. The diode can would still be cool, however the emitter in the unit would be completely dead.

 

[bootleg2go]

Thanks for the information, I really didn't think it was temp related as I had also tried putting the leadlight in the freezer for awhile, and even when freezing cold, it would still drop off at the same rate.
If anyone reading this post has modded their own glp-110, does your power output dropoff like mine does?
One other question Spec, If what your saying is true and I'm not saying it isn't, just trying to understand and learn more, then why is it that many here talk about how their laser needs to "warmup" for a short period of time before it reachs it's full output power?

Thanks
Jack

 

[Spec]

Available stock at the manufacturer /ubbthreads/images/graemlins/wink.gif

I have one pointer that exhibits symptoms like yours. Its a unit I installed a 808nM diode in. It starts out perfect, maybe 1 second off from peak and then just fades out after about 10 seconds.

Others here (mostly leadlight owners) have diodes that start out at 805-806 and when they run it it shifts up to 808 and beyond after a little while, rather brilliant move in my opinion. Either that or they are in a colder environment and they dont carry their pointer on them(body temperature).

As usual, there are variables involved that I dont know and could not get access to without having your pointer here.