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100mw 520 module from techhood/ebay

GSS

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Your right, it isn't right to advertise it that way.. It took me half a day to realize the green looked a bit different than a 532 even.
I tried all day to light a match also. Shut all the lights off to darken the room and still barely saw a beam. I was actually more excited for a 100% duty cycle beam to lay back and relax and watch it than burning.. Now seeing even if I could drive it up, 38mw isn't the best beam profile.. Finally looked through the front with a flashlight and saw no 532 added lenses..
That front cover was just a thin tin piece that mangled coming out.
 

CurtisOliver

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Yes, I remember you saying about yours Peter. Yep, definitely no 532 DPSS. I'm starting to wonder whether yours is a 505, or an overdriven 510/515 like Roberts?
 

RedCowboy

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I wondered why the heat sink never gets the least bit warm and the output slowly trickles down, well the heat sink is just for looks there's a plastic spacer that prevents the large black heat sink from doing anything, it's a 5.6 diode with 4 pins one appears to be a case pin and there's probably a photodiode as I bet these are used in devices limited to 5mw.
The can is a thick brass looking deal with a small output hole and I don't see any window.

Anyone know diode this is ?

643056430664307643086430964310
6431164312
 
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GSS

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Wow.. That's a strange one..
Mine just might have a plastic piece over the module but it's black. Same blob of white glue on the back of the diode.
Maby I can post some pics.

Edit: Looks like I have the exact same unit.. What I thought that was a black spacer looking down the front was the reflection of the black anodizing that's alot thicker in the back half off the heatsink.
From the back you see the same white plastic sleeve, and the 2 prong connect that's on the side 2 pins of the 4.
 
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RedCowboy

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They probably got a deal on some out of spec diodes made for 5mw consumer products, hence the case pin and feedback so they can be used in a wide variety of devices, the heavy brass housing would let a it operate in plastic at 5mw.
 

paul1598419

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Man, that is a major disappointment. I wouldn't have guessed they used a plastic spacer to completely nullify the lab host. That is total nonsense.
 

RedCowboy

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I expect it was simply a matter of sizing to make the little aluminum heat sink fit which is sloppy and overdriving what looks like a 5mw laser diode to the edge of foldback to put out 39mw and advertise it as 100mw is no doubt intentional and discouraging.

I wouldn't have been upset if it was at least 85mw and over 100mw would have been nice and I would have bought more, but I will look at anything they sell " built/assembled " with a jaundiced eye from now on and likely only buy parts they didn't build.......funny thing I also discovered that my 200mw 532nm modules that I had bought from techhood are not 200mw, they are 125mw but I have had them for over a year so I won't complain, I also won't buy anymore.

On a positive note I have won some nubm/nugm diodes at auction that are good deals although I am pretty sure I got a ndg700 in place of a ndg7475, but it was still a good deal.
 
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paul1598419

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Those 200 mW 532nm modules are actually up to 200 mW. I bought some years ago and they will come in at 190 mW if you heat sink the output transistor and set the drive current at max.
 

RedCowboy

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Yea but are you not overdriving the 808nm pump past it's spec. ? They should be doing near 200mw out of the box but there not.
 

paul1598419

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Not at all. These drivers only apply less than 1000 mA of current to the pump diode. Typically 700 mA. These are 1 watt pump diodes.
 

RedCowboy

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Come to think of it I have had to adjust these before when they arrived weak, it's been a while since I worked with the small China dpss modules and they don't typically use an oversized driver capable of killing the pump diode but they could.........although I don't remember ever killing one by turning it up and they were often at/near peak.

I have had many that were working well then start mode hopping out of the blue and I am talking about low use modules in a good heat sink so I haven't been buying them lately, haven't bought anything 532 except some 303's because they are so cheap.

I adjusted this 1 techhood 532 ( was advertised as 200mw when I bought it ) that I have loose ( in a heat sink ) and it's not doing any more than 127mw, I also have 1 that was doing about the same and now will only do 95mw. May have been 150's sold as 200's and I have not measured the current but I suspect the 150's are less efficient crystal 1w 808 pumped 532's so it would be the same 800ma driver in theory, 100mw 532's should use a 500mw 808 and 400ma driver and 50's use the 200ma driver and 1/4 watt 808 but they could also be less efficient 500mw 808 pumped crystals.
The reason is I have bought 800ma drivers and 400ma drivers as well as 200/300ma but I have not seen any 600ma 808nm pump drivers so I expect the 150mw 532nm modules are the same animal as 200mw 532nm modules only the crystal is less efficient and I would not be surprised if I had received some 150's in place of purchased 200's
 
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ronaledsmith

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I won a 100mw 520nm module from techhood on ebay, I have bought quite a lot from techhood but this module is clearly underspec.
I also tested the TTL input and still it would not do more than 39mw.
If you buy from ebay be prepared to deal with crap like this.


View attachment 64208

View attachment 64209

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Great
 

GSS

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Come to think of it I have had to adjust these before when they arrived weak, it's been a while since I worked with the small China dpss modules and they don't typically use an oversized driver capable of killing the pump diode but they could.........although I don't remember ever killing one by turning it up and they were often at/near peak.

I have had many that were working well then start mode hopping out of the blue and I am talking about low use modules in a good heat sink so I haven't been buying them lately, haven't bought anything 532 except some 303's because they are so cheap.

I adjusted this 1 techhood 532 ( was advertised as 200mw when I bought it ) that I have loose ( in a heat sink ) and it's not doing any more than 127mw, I also have 1 that was doing about the same and now will only do 95mw. May have been 150's sold as 200's and I have not measured the current but I suspect the 150's are less efficient crystal 1w 808 pumped 532's so it would be the same 800ma driver in theory, 100mw 532's should use a 500mw 808 and 400ma driver and 50's use the 200ma driver and 1/4 watt 808 but they could also be less efficient 500mw 808 pumped crystals.
The reason is I have bought 800ma drivers and 400ma drivers as well as 200/300ma but I have not seen any 600ma 808nm pump drivers so I expect the 150mw 532nm modules are the same animal as 200mw 532nm modules only the crystal is less efficient and I would not be surprised if I had received some 150's in place of purchased 200's
Glad I re read this and the theory..

I'm noticing the Aptlighing 200mw 532 module that Paul set up for me is only giving me maby 3 or 4 minute's "total" of 190mw+
No No Paul this isn't aimed at you, you set it up nice..;)

I run it for about 5 to 10 seconds on and 20 to 30 seconds off 2 or 3 times at start as it's not cold in my house but just a bit chilly outside to maby warm up this 532.
I can meter it for about 30 seconds and have gotten 195mw+ peak and a more stable 170mw but after the 3rd or 4th test with at least 2 minutes cool down it will drop to around 80mw or 90mw..
At a 1/2 hour of no run time it will not recover, it needs a good 2 or 3 hours to max out again into the 190mw's.
The back half of the module and importantly over the pump diode it's heatsinked and so is the driver. The module sink isn't huge but is 5/8 in. wide by 3/4 in long aluminum. Like I mentioned I run it no more than 30 seconds..

Total understanding these are over pumped modules with a 1W initial pump but would expect a bit more run and especially way quicker recovery time.
Are the crystals saturated with so much heat that they need hours to recover??
 
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RedCowboy

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Could be the pump diode or crystal or the driver or any combination of them all, I have seen all kinds of stability issues with the dpss modules, some will do continuous duty in a good heat sink without any active cooling but many won't hold their output.........you could heat sink the driver and see if it helps or not.
 
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GSS

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The driver was sinked from Paul with a nice little finned aluminum piece that kinda dwarfs the driver.
I didn't use any thermal paste on the module heatsink though from fear of getting it on the lens and plus wasn't sure to where I would put this module in and didn't wan't the paste mess incase I were to put it something else.
I did shim it the best I could with .005 inch of copper sheet.

I have a Fasttech module doing 124mw's that'ss surprisingly very very stable and that's with a .500 pump but other Fasttech's that are way weaker and are all over the place.. At $6 each for the Fasttech's it's not a big deal but frustrating.
 
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RedCowboy

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Some crystals are more efficient than others and they sell the more efficient crystals for more money and use them in the higher quality modules that sell for more money.

Granted the Chinese have become much more proficient and are making better modules today, but they do bin them by their range and they are not all created equal.

I expect they use 250, 500 and 1000mw 808nm pump diodes in the basic springboard 532's and I'm sure they still bin the modules according to where they are most stable at least in a quick test, but you can't really expect to get 200mw from just any 5 dollar 532nm module by pot modding it, not a stable 200mw

I have a few dozen survivors and 50-100mw is common but modules that put out a real 200mw I haven't seen many of and I paid a lot for some advertised as 200mw, again today they are better and I haven't been buying many but the 5-8 dollar units lately but I have quite a few that didn't hold up and developed issues such as coming on bright and fading fast, just how much you can push what they make today and how long it will hold up is likely proportional to the cost range of the modules and their rating, I expect modules rated as 100mw will take it much better and last longer than 5 - 30mw rated modules when pot modified for max output.

p.s. A decent heat sink is a good idea for anything modified if you want it to last and hold output, heat is the enemy.

I have thrown away most but here's some of my old 532nm boneyard.
64784



---edit---

Are these what you are using ?

It says 3v at 250ma so the pump diode can't be more than a 500mw as no driver is 100% efficient and diodes are around 50% .


I just ordered some with fast shipping ( still 8-12 days ) and I will pot them up and test them in a good heat sink with the chip sinked as well and post what I get.
 
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