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FrozenGate by Avery

New DX Green MODULES

Got one 100mW today. It sucks. 40mW. In the garbage now. At least it didn't mode hop. I have 3 more on the way.
 





Sorry I didn't clarify, my nephew was adjusting the potentiometer while I held the connections and we shorted the laser out. Dead diode.
 
Prelim Review of New DealExtreme 100mw Green Module -

When I first got this, the package was badly mangled, so when I noticed while unwrapping the module that the driver was not firmly attached, and was moving in relation to the module, I thought to myself - "OMG, did they break-off the diode pins in transit???" :huh:

But when I got it unwrapped and examined it closely, it turns out that the driver was free-spinning because the small piece to which it was attached had not been screwed-in all the way!

It turned-out (a major benefit for this DX design), this module consists of several modular components that are threaded, and can easily be disassembled - Cool! :yh:

Initial impression is that the 100mw one is likely a 200mw one that did not pass Q/C at full strength, given that I found at least one issue with the unit that could potentially reduce output power.

Both the overall length, and the individual length of the assembled brass module and driver board, are all slightly shorter than my O-Like. Only size issue is that fat resistor (yes, it DOES have that), one end of which is sitting on top of the regulator IC, and extends out slightly farther than the outer edge of the brass module, so fitting in a tight pen host might cause a problem.

The module itself can be easily disassembled into 3 threaded modular components, the driver/lasing module, the beam expander/containment module, and the collimator/focusing lens module. I will describe each of these in turn.

(Note - examination aided by my 30x jeweler's loupe, great for looking at tiny SMD designs, DPSS crystals, diode innards, etc.! :yh:)

DRIVER:

The driver, even though shorter, appears to be possibly superior in design to my O-Like. It has an 8 pin regulator IC that is controlling a separate driver transistor. The big resistor (if I am decoding it correctly) appears to be a 0.33 ohm, with 1% precision.

Examination of the driver under magnification, however, reveals rather poor soldering, with some poor/barely attached solder connections, some semi-cold soldering joints, and splatter all over the board. :( Also excess flux all over and bubbling-up from some joints - appears board was not cleaned/de-fluxed after soldering? :confused:

Pushbutton switch takes a lot of pressure to depress (possible problem because of the way the driver board is mounted - see below). Two color-coded leads. Black lead connects to back/center of driver, making is appear fairly easy to replace with a spring. Red lead attaches towards front of board, has clear plastic goo insulating where it attaches - rather strange, as red lead connects to case pin on LD!

One corner of board barely touching back of brass base, other corner actually has slight gap between it and base. Unlike the O-Like (which has glue on both sides holding the driver board securely to the module), the driver board is ONLY supported / attached to module via the laser diode pins! :eek:

DIODE/DPSS MODULE:

Diode has 3 pins, in a flat-based triangle arrangement, with the peak of the triangle being case ground. Hard to tell with stuff in the way, but based on pin spacing, diode also appears NOTICABLY larger than the one on my O-Like. All 3 pins are soldered to the driver. Diode appears to be held in place from the back with something similar-looking to a lens nut (but deeper), with notches on each side.

Outside visible portion of diode/DPSS module is surprisingly short - only about 4mm (about 1/2 that of the O-Like). Majority of it extends inside, and has threads which screw it into the next module.

Inside the diode/DPSS base, it is apparent that the diode is a sizable open-can variety. There is an extended C-shaped piece of metal about 3mm tall glued to the top of this module, which contains the crystals. It has a deep notch to hold the crystals, which does not extend quite to the top, but opens-up near the top inside of the piece.

The SHG crystal is rectangular and long. The end is square, and slightly less than half the width of the notch. It is pressed into one corner of the notch, so that two sides of it are heat sinked to the metal, and held in place with a large glob of white glue-like substance (It is not possible to see the vandate crystal, or whether the two are one piece, because of all of this glue). The end of the crystal extends slightly past the top of the notch, and thus is not heat-sinked.

There appears to be a defect or foreign substance on the coated face of the crystal! :wtf: Examination revealed this to be a streak of that white glue, stuck to the face of the crystal - apparently they applied this stuff too liberally / sloppily! :tsk:

Luckily, closer inspection revealed that this streak of glue was along the same horizontal direction as the laser diode die, but was located vertically aligned with the base BELOW the die on the laser, and so appears to be out of the beam path - Whew!
(Although I am curious if this substance on the crystal face could still cause problems?:undecided:)

The side of the crystal has a rough texture, white and with what appeared like veins, similar to what a piece of quartz rock (not crystal) looks like. Looking inside the crystal from the top, typically appears sections light and dark green, but occasionally dark violet, depending on the angle and lighting. One thing I did notice was angled lines of dark green (hopefully not fractures inside the crystal!), perhaps someone more familiar with these crystals can let me know if these lines are normal?

BEAM EXPANDER/CONTAINMENT MODULE:

This module wraps-around and "contains" the DPSS section of the module below. The visible outside portion of this module is about 9mm in length. It is closed and thick at the top, with a narrow "light tunnel" drilled through it. (It is hard to tell with the attached piece, but it appears this may extend out past the top).

Glued to the top of the module is a piece similar in shape to a brass spacer, but wider, and about 4mm thick, and which appears to contain a negative lens (viewing through both the magnifier and this lens results in focusing at infinity), presumably used as a beam expander.

Unfortunately, this piece is glued off-center, such that the expander lens and the light tunnel below do not line-up fully, blocking part of the path below. Hopefully this is not blocking part of the beam! (This may be why this unit was rated at 100mw?:rolleyes:) Not sure if this is fixable or not.:confused:

COLLIMATOR/FOCUSING LENS MODULE

This is the longest of the brass sections, with a base extending about 12mm long, which then narrows, and then extends about 1cm, about the last 7mm of which is externally threaded. There is a long, black spacer inside of the threaded portion behind the lens. While the end of the module is narrower, surprisingly, the lens itself appears to be wider than the O-Like!

The lens nut has two shallow "dimples" rather than the more traditional notches. The lens appears to be located as far out as it could be, and the aforementioned spacer prevents it from going any deeper. The lens appears to be designed to just collimate/focus the beam from the beam expander, and NOT to support adjustable focusing.

There was some theorizing before about the purpose of these external threads. Given the thickness of the metal at the end, the fairly small outside surface area of the (heat generating) diode/DPSS module, that this appears to have been designed to use all three screw-on pieces of brass as one big heat sink, (carrying the heat forward and away from the LD), and finally the fact that this is not some hobbyist "mod", but was designed from the get-go for high power - IMHO all of this point to the use of these threads to mount to dissipate heat, ether to a metal case, or a supplemental heat sink, one that could press against the flat lip below the base of the threads, and perhaps even wrap-around the module.

This might also eliminate the need for a set screw. You could also build a pretty neat-looking "screw on" heat sink accessory for such a laser - a "screw-on silencer" design! :cool:

BTW, styropyro, you said the pics on DX looked like the modable ones you pulled out of the True 5's. Did they also come apart like this one? Does it have the same resistor & colors - Black Orange Orange Silver Brown? My description should be detailed enough for you to be able to tell us if it is indeed the same driver and/or module you were referring to?

After detailed examination of the innards and hours of work, my PC crashed while I was finishing this, vaporizing most of my review! :banghead: Arrrgh! So beware most of the measurements are a bit rough, and from memory. Likewise, don't shoot me if I made any mistakes - I wanted to get this up for everybody as quickly as possible, and plan on editing / adding to / improving it afterwards.

Overall, I would say that while the construction quality was a bit lacking (and may impede the performance of the unit), I think the physical design is better than my O-Like, and both the driver and diode also appear to be heavier-duty than my O-Like one. So a mixed bag, whether these stronger components actually follow-through with stronger results during testing will determine if I rate this one thumbs-up or down.

Finally, I haven't had a chance to "flame-test" this guy yet (I do not yet have a proper host, batteries, or an LPM). I'm also thinking that trying to juggle two batteries, test wires, and a bare high-power unfiltered module, indoors and at night without goggles, is PROBABLY not the best idea! Once I can find / get access to the right stuff, I will see about posting some performance #'s on this guy!
 
Great review of the build! Pics Pics Pics of this module doing what it does best? :D
 
Great review! Can't wait to see the rest although as previously stated I don't expect much performance wise from this diode.
 
I tested mine 2 days ago:
Unfiltered reading was 123mW.
The beam was horribly off center and blocked by the module, so I fixed it.
Output climbed to 154mW.
Beam was bright. I'm assuming 125-135mW green.
Beam quality was surprisingly good: stable TEM00, not many artifacts... just poor alignment.
Good value.


Then the damned thing died before I finished testing.
Awaiting autopsy.
 
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Mine arrived yesterday - cold solder joints, one pin of the laser diode had broken free due to the cold solder joint.

I heated and fixed all the cold joints and applied power. No dice. DOA :(

I removed the driver and tried directly powering it with an LM317. Still no dice, diode is blown open circuit.

I reassembled the laser and will be sending it back to DX.
 
Whoa these are turning out very, very bad!

baboo1bx.gif


Sorry to hear that, guys... DX needs to take care of this.
 
Well hopefully these greenies will be useable... DX sent me an email yesterday that my stuff got shipped... patiently waiting... I ordered a bunch of stuff. The condition in which all of these (tools, parts, greenie modules, etc.) will arrive will determine whether I will remain a DX client or not.

Many thanks SEOGUY, that was a very insightful review. I'll know what to expect when I start playing with these. Somehow, I have a feeling i'll be using a lot of 99% Isopropanol, acetone and CCl4 when theshipment arrives. :D

Robert
 
I would recommend to anyone purchasing these:

Watch the amount of voltage you pump into these
Heatsink the driver
Disassemble the module and apply some thermal adhesive (if you have some silicone or arctic silver glue) around the crystals. They are glued above the diode with not much brass to keep 'em cool.

I will be using the crystals to resurrect this laser. The diode will be cheap to replace (I may even get one of the cheaper modules and take the diode out of that).
I'm surprised I got the amount of power out of the (tiny) crystals that I did, although I cannot say for sure how much was IR.
Rebuilding will be pretty simple so I don't think it was a real waste of money.


Oh- and one more comment... DX shipped mine (along with all the other goodies I ordered) in a deflated bubble wrap envelope. The module was in a plastic bag with no other cushion. I'm surprised nothing was knocked loose or broken when I got it.
Thumbs down.
 
I'm still waiting for my 200 mW module to ship. I ordered on 8/1. My hopes are looking bad.

Mike
 
Great review of the build!

Thanks, millirad! :yh:

Great review!

Thanks for the compliment, and the +Rep, ZRTMWA - MUCH appreciated! :thanks:

Many thanks SEOGUY, that was a very insightful review.

You're welcome, roddenberry! :yh:

Somehow, I have a feeling i'll be using a lot of 99% Isopropanol, acetone and CCl4 when theshipment arrives.

Carbon Tetrachloride??? Isn't using that stuff slightly hazardous to your health? :rolleyes: Be careful!

The beam was horribly off center and blocked by the module, so I fixed it.

RA_pierce, did yours have the same alignment problem with the expander lens holder on top of the middle brass piece that I described with mine? If so, how did you fix it?

Output climbed to 154mW.

I suspected that the off-center lens holder on mine might cause a loss of power sufficient to get it re-classified as a 100mw unit, and that fixing that could bring it up to full strength. If you are describing the same problem, then that might be true for mine as well! :yh:

Then the damned thing died before I finished testing.

Ouch! :cryyy: I know the guy on DX who bought the 20mw had his die as well, but he attributed the burn-out to pot modding. Were you adjusting the pot as part of performance testing? Had it been on for a long time? What were you doing with it at the time that it died?

Awaiting autopsy.

Based on your later post, were you able to confirm the cause of death was a blown diode?

If so, could they have been pushing the diode too hard?

Watch the amount of voltage you pump into these

I know there are some defective hobbyist driver designs going around right now that do not regulate current properly, and are thus susceptible to increases in supply voltage.

But this is sounding more and more like the driver may be over-driving the diode?

Can you try something for us? Hook a dummy load up to the driver, and see what the output current is on this thing?

Then perhaps try altering the supply voltage, and see if the current holds steady - or goes up?

Thanks! :yh:

Oh- and one more comment... DX shipped mine (along with all the other goodies I ordered) in a deflated bubble wrap envelope. The module was in a plastic bag with no other cushion. I'm surprised nothing was knocked loose or broken when I got it.

Mine had packaging issues as well! I wonder if that also could have been the cause (along with a cold solder joint, and the poor method of mounting the driver mentioned in my review), for MarioMaster's pin problem?

Beam quality was surprisingly good: stable TEM00, not many artifacts... just poor alignment.

That seems similar to what my examination found - good design, but poorly constructed. But given many of these units seem to have obvious manufacturing defects, raises an interesting point -

Is DX buying the "manufacturing rejects" of modules designed for use in, say, a high-power green RPL, and then re-selling these defective modules to us???

Disassemble the module and apply some thermal adhesive (if you have some silicone or arctic silver glue) around the crystals. They are glued above the diode with not much brass to keep 'em cool.

Something I noticed when I was examining these under magnification - both the crystal holder, and the expander lens holder, were not glued flush with the module, but were sitting on TOP of glue, so there was an air gap - I'm wondering if they were deliberately trying to thermally isolate them from the heated brass case?

I'm surprised I got the amount of power out of the (tiny) crystals that I did

It was hard to tell with all of the white stuff, but the KTP crystal appeared to be at least 2mm long. After I examined the crystals, I did a little searching for similar-looking ones elsewhere, to get an idea on their ratings.

O-Like pics were next to useless, and didn't appear to have anything that matched, but I did find this on eBay -

75mW GREEN beam LASER MODULE DPSS CRYSTAL UNIT KTP

A used DPSS unit that appears to have been torn from a 75mw greenie(?), 1x1x2mm crystal, pump with 500mw 808nm and get 75-100mw 532nm out, claims crystals capable of up to 200mw! -

75mW GREEN beam LASER MODULE DPSS CRYSTAL UNIT KTP - eBay (item 290341361237 end time Aug-23-09 23:49:27 PDT)

The crystal shape and specs seemed right, but the holder was different - it didn't have that indentation above the notch -

23012d1250942855-new-dx-green-modules-crystal1.jpg


But then looking at other stuff, I found pictures of what looked like the same thing, crystals again rated for 500mw 808 --> 100mw 532 out, but this time, pictures of BOTH sides of the holder...

23013d1250942855-new-dx-green-modules-crystal2-1a.jpg


23014d1250942855-new-dx-green-modules-crystal2-2a.jpg


Look familiar?
;)

But if these are designed for ~100mw out when pumped with 500mw 808, it raises an interesting point. Given that conversion efficiency in the SHG crystal increases with power density, pumping these with a 1W diode would more than double output power, and likely kill them! :eek: They could be running a 1W at well below full power:thinking:, or perhaps...

What if DX is pumping these with 500mw 808's, and severely over-driving the diode in order to get the higher power out of the crystals?

That could certainly explain the short life expectancy!

That fat resistor might be the clue, if we had all the right numbers. Does anybody know what the voltage drop and current draw of a typical open-can 500mw 808 is, when running at full rated capacity?

This also re-confirms the importance of measuring the output of that driver!

Mine arrived yesterday - cold solder joints, one pin of the laser diode had broken free due to the cold solder joint.

MarioMaster, sorry to hear that! :cryyy: Did your package arrive mangled as well - does it look like it broke free in shipping due to poor packaging?

Mine likewise had poor/cold solder joints. Was your driver also only supported by the diode pins?

Still no dice, diode is blown open circuit.

Which pin came loose - do you think that ESD to the disconnected pin perhaps killed your diode?

Hey, if it's your diode that died, could you try something for us? I'm working on a theory that these may have a short life expectancy due to being over-driven to get >100mw out. Can you try connecting a dummy load to the driver, and see how much current it's set to?

If your diode is truly blown open circuit, you could probably do this without even disconnecting anything?

Thanks! :yh:

I've yet to hear of anyone who's module worked for more than a short while. :anyone:

Now I'm afraid to power-up mine! :undecided:
 

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Seoguy:
To fix the alignment issue I removed the expander lens/OC and glued it down so that the beam was more centered with the collimator lens. After I accomplished this the beam still exited the aperture at a large angle (est. 20-25 degrees from center). This makes me think that the crystals are not aligned properly, throwing off the whole optical assembly.
Alignment of the lenses definitely has an effect on power.

When my module died I was testing the alignment... I powered it with an 18650 at 3.4V.
It's possible that the driver does not regulate voltage very well and the over-voltage killed the diode. If this is the case, these may not be able to be run on rechargeable lithium battery types at all without significant risk to the diode.
I did not adjust the pot. I only had it running for 5-10 seconds at a time to inspect the new alignment of the lenses every time I made an adjustment. I put the module in a brass heatsink for additional cooling.

I have not yet tested the cause of death, but I get zero output from the diode. This means either the driver is malfunctioning or the diode is really cooked. Normally with dead greenies I get the "dim red glow."
I can't test the driver at the moment as I have no dummy load (lost) and I also lost my good multimeter. Yeah... I know... :(

I suspect the diode is either 1W and being driven at around 800mW or 500mW and being over-driven to well beyond it's rated limits. I have never cooked a crystal set (even a 20mW one pumped with 700mW) so I think it's most likely the diode or the driver that is dead.

Either way... I agree that they are using decent components but just doing a lousy job of assembling them.
Although as I mentioned... the crystals are tiny... they are smaller than those found in CNI pen type greenies. The crystals from my X50 are about 2x2x3mm... the crystals in the DX module are about 1x1x2.5mm.

I will hook up the diode to a working driver and test it to see if it's really a dead pump... but I'm a little busy so I will get to that probably tomorrow.
 





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