Leadlight 105/110 Modification Stages1,2

[HD58PHD]

Hi,I don't think z-bolt sells leadlight.
More likely Lightvision,as I have one of their modules,and it is the latter.

 

[buster]

the beam of my laser isnt going straight out, its going out ant a slight angle. anyone know how to fix this? ive only dont the pot mod.

 

[GreenMachine]

i recently bought a green laser on ebay, not really knowing which brand was the best. the one i got is a leadlight from luckyduck, and has APC. does this mean that no matter what i do to the pot, it wont get any brighter? i read that the negative feedback circuit that is in these APCs prevents the output from going higher than 5mw....i hope this is not true :\

 

[Databyter]

If you read the modification threads you will see that yes, an apc will limit your ability to do a simple pot mod unless you disable or bypass the apc.
I assume this isn't really too easily done unless you have some very fine tools and a big magnifying glass and the steady hand of a jewler or laser mod'er

Maybe you could sell the one you got on ebay and get another model?

Or better yet just buy a pre-screened pointer that will provide you with the power you want/need from a reputable dealer.

 

[Rich_UK]

Hi all, first post from laser newbie 🙂 I just did the pot mod on my green leadlight (from vital*spirit), after pulling the button off I discovered the hole in the plastic cover was already there, I thought damn it's already been modded so I wont be able to boost it, wrong! using a jewelers screwdriver (covered in black tape) I carefully gave the pot screw a little turn (with the button pressed and watching the dot on a white wall), and was amazed with the instant result :wow: so I carried on turning until it went off, and then back a little, my laser now works way better than before, but just one thing....... for a brief second it's very bright, but then it suddenly dims a little, don't get me wrong I'm still very happy, and it's still loads brighter than before, but it would be great if it would stay at the intital power, according to my battery tester the batteries are still good, but at the moment it's still running on the standard ones that came with it, would rechargable NiMH batteries help?

P.S. a big thank you to you LaserMod for putting in the effort to make this guide for us newbies, it's much appreciated :twothumbs

 

[DFiorentino]

I too just bought a leadlight "105" from vital*spirit and attempted the pot mod only to encounter a strange result. (Oh, and mine already had the hole beneath the button, but i removed the unit from the tube just to make things easier.) When I initially turned the pot, I got the same result as Rich_UK above. At first bright, then the APC circuitry kicks in (as I'm understanding these more recent "Vital 105/110s" have?) and the laser dims back to almost stock brightness. Frusterated, I hooked up a amp meter and adjusted the pot to the very edge of my maximum power reading which was 300ma. This took several press on-turn the pot-read the meter cycles, so that I could get a reading before the laser dimmed. Now, when I turn it on, it comes on bright, then dims as before within @5sec....but after @30-60sec. on it goes very dim to almost off then brightens back up and then back to the initial full brightness. :huh: If I press the button again in a short period of time, it does the sames thing, but all in a matter of @1-2sec. :thinking: However, if I let it sit and cool, it'll go back to the 30sec. wait deal. Its at the brightest almost immediately once it warms up.

Kind of wierd. Kind of frusterating. Yet, kind of cool that I seem to have one of the few newer Vital Leadlights lasers that have some sort of positive effect with the pot mod. ...or I'm just setting my laser up for a short lived life .

-DF

 

[Corona]

Sounds like a Vital 110, not a 105. The Vital APC ("110") driver circuit is really unstable, especially if you turn the pot up past the point where the laser can actually deliver the power that the pot setting corresponds to. The APC circuit "wants" to see more green than the assembly can actually make, so it tries to increase the LD current to get there, and can't...there is a horrible current oscillation that can kill LDs if you take the trouble to mod the driver so it can exceed about 350mA (or happen to encounter one that responds to the pot mod, as you have). Be happy that yours caps at about 300mA. The result of this current oscillation is the intensity modulation that you see. Thermal response/drift of all the interrelated laser parts (LD, Nd:YVO4 crystal, KTP doubler) all affect the green output - and the poor APC design is not compensated for these effects.

The Atlasnova 110 is a slightly better APC circuit, but all over-simplified APC designs such as these are subject to the runaway condition. It works fairly well at a reasonable level above the laser diode threshold (~200-250mA), but once the overall system enters into a non-linear response condition, all bets are off.

Simple as 😀

 

[Hack]

Hey, I to am very new here. I've done mods 1 and 2 and ready to do the resistor mod. I know where the resistor is to be replaced but don't know what size of resistor to put there. Can you guys help me out?

 

[Athoul]

Also the initial power fluctuations are caused by the crystals reacting to the sudden activity. The laser then dims to it's actual output ability. Note that heat is a factor as well. As the laser gets hotter the crystals start to perform differently, this also occurs when they cool down...and you can notice increase/decreases in beam brightness. Most, if not all DPSS lasers are known for this :/

 

[blinkest]

I recently bought a black/gold-colored Leadlight 110 laser pointer off of eBay and attempted the "pot" mod. First, I removed the button, but instead of the whole there was only thick black plastic. I then drilled through this but when I got through I realized the pot was about 1 cm out of reach!

Now no matter what I try -- using the sharpest knife I can find, using pliers, scissors, and about everything else that comes to mind -- I can't get the pointer disassembled! All I managed to do was to severely scratch the aperture cap and completely wreck the paint job.

Does anyone have any hints for me to defeat this mysterious unbreakable force?

 

[Databyter]

My dad has always maintained that there is nothing that a 4 pound hammer can't fix.

I'm not sure his defnition of fixed is the same as ours however..
Sorry about the paint job and difficulty. It sounds kind of frustrating. You can always refinish it though once you get it modded.

Personally I would think a pair of rounded jaw vise grips would do the job of getting the cap off. Don't grip it too tightly or you will defeat the purpose.

If nothing else the 4 pound hammer would be satisfying for a few moments.

Good luck

 

[Hack]

Hey, I to am very new here. I've done mods 1 and 2 and ready to do the resistor mod. I know where the resistor is to be replaced but don't know what size of resistor to put there. Can you guys help me out?

I guess not!!😡

 

[Robban]

I guess not!!😡

Dude... It's only been a couple of days since you asked. And even if it was a week ago no one here has any obligation to answer any of your questions. We're all regular people around here sharing a common interest. No need for that kind of attitude, even less so when asking for help.

 

[Robban]

Ok. Today I became the proud owner of my first green laser. I got it at day time and of course ripped the package apart and turned it on. OOooh I thought to myself that's pretty darn bright. Came home now tonight at dark and tried it again. This time I went WOW, this thing is crazy it lights up my entire room.

Now... it didn't take long before I decided to do the pot mod. I slowly turned the pot and this time I went HOLY CR@P! the spot on the wall was too bright and I stopped turning before I reached the max, this thing scares me 🙁 I measured the output using the green led method before doing the mod and after. I measured an output 8 times higher than before, and I haven't maxed it out yet... Is that normal?

One other thing. I'm now scared to use this thing without squinting and kinda looking the other way (or covering my eyes and admire the beam). Is it safe to look at the spot as it is reflected off a light colored wall? Or should I be getting some safety glasses? (I'm thinking I should get them anyways though).

Thanks for the excellent tutorial!

 

[Athoul]

As long as the reflections are off of a non glossy surface you should be ok, just be careful of reflections from shiney objects, glass and mirrors. Sounds like you got a good one, It's possible you tweaked your laser up to 15-40mW, if it's in the higher end of my estimate you might want to buy some goggles. I would say around 30mW is getting risky for the eyes, I read the US army uses 25mW and considers them to not cause permanent damage, although I personally think the chance of eye damage is greater then they are claiming.

 

[Robban]

As long as the reflections are off of a non glossy surface you should be ok, just be careful of reflections from shiney objects, glass and mirrors. Sounds like you got a good one, It's possible you tweaked your laser up to 15-40mW, if it's in the higher end of my estimate you might want to buy some goggles. I would say around 30mW is getting risky for the eyes, I read the US army uses 25mW and considers them to not cause permanent damage, although I personally think the chance of eye damage is greater then they are claiming.

So a whiteish wallpaper should be ok then. And a carpet for example should not pose any problems either I suppose. I will still refrain from looking straight at the dot though, but it's good to know I'm not gonna go blind just by catching a glimpse of it here and there 🙂 Now that I'm not feeling quite so worried (still have a huge amount of respect for it though) I'm going to try to crank it up a wee bit more, just to see if it'll go any higher and then turn it back down again.
edit: Turns out I was pretty darn close to the max as it was. I however took a little drive out into the woods and tried it out in the snowfall. OOooh pretty! 😀 But of course, the one car I met had to come just as I was trying it out in a clearing, so I had to pull out my flashlight and pretend to fix my wipers 😛

 

[Robban]

Ok guys... I think I've messed up 🙁 I was trying to pot mod today again. Pulled off the button as usual and used a small screwdriver (it has a magnetic tip but that shouldn't be a problem right?) that is taped all the way except for a tiny tiny bit at the very end (less than a millimetre). I was turning the pot and it got a little brighter, brighter still and then it went dim. That's what I was expecting by reading the instructions. So I turned it back a bit, but it didn't seem to get back to full brightness again. I've now tried to turn it a couple of turns in each direction and it now goes from dim -> little brighter -> dim and then repeats. It's not even putting up much of a fight against a 5buck red one now.

Why can't I ever leave stuff alone! I hate myself right now :/

Have I destroyed my pointer? 🙁

edit: How can I test if it's broken or not? Can I bypass the pot by putting a resistor in the whole and connecting it to the side of the button opening? If so, what resistor value should I be using. Anything else I can try? I reeaaally don't feel like throwing out another 60 bucks...

 

[Corona]

Sounds like you have damaged the laser diode, alright. The pot has no stops at the ends of travel, so your description of the brightness variation makes sense. Unfortunately, once you had adjusted it past the LDs maximum allowable current (the driver board is capable of applying far tooo high a current, yes), and operated it, the LD was internally damaged. Either the die was damaged, or more likely, the tiny mirror facets are ablated/cracked from the excess infrared power. It still lases, but the output power is way below spec.

I don't recommend adjusting any stock pointer above about 300mA, and tweaking the pot without monitoring the current - that is like playing Russian Roulette. You need a new LD, almost certainly. Ouch.

Now you have what can affectionately be called a "parts laser". Welcome to the club 🙁

 

[Robban]

Well that royally sucks don't it 🙁 I thought I would be ok as according to the guide it would never go over spec by just doing the pot-mod (I'm not blaming the author for what happened here though, you didn't turn the pot, I did).

So I guess I'm SOL then? This sucks. It's not that I can't afford another one, it just feels stupid to waste money I could've spent on a tank of gas on getting another toy (yeah, gas is expensive over here...).

 

[Corona]

Ja...det er meget dårlig, kanskje du vil være mer heldig og kjøpe en med meget kraftig!!

LOL Norsk is as close as I can get to Swedish - and mine is pretty bad!

Yes! Buy another, and modify with more care, you will be OK

vennlig hilsen 😀