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eBay gambles: how I got a 25mW 488nm DPSS for $75...

aryntha

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Yeah, some people are gonna be angry at me for lucking out like this...

A discliamer first, I rarely "luck out". As some vets here can attest to, I've had more ebay losses than wins. I have a pile of "dead soldiers" I chalked up to a loss, and the 'tuition price for learning'. ArIons, HeNes, DPSS, you name it, i've blown a deal on a dead one, or been taken for a ride.

That said, this was a risk. Not a huge one, but a risk nonetheless. To make a long story short, I saw an eBay auction for a broken laser: a "JDSU FCD488FC-20". The auction said clearly:

Condition: For parts or not working: An item that does not function as intended and is not fully operational. This includes items that are defective in ways that render them difficult to use, items that require service or repair, or items missing essential components. See the seller’s listing for full details.

For the uninitiated, the above translates to one word: BROKEN.

Furthermore, the seller's description was as followed:

Item Details:

The pictures show the actual item as you will receive it. This item is in used but good physical condition, and it is sold "AS-IS" for parts or repair. My research found that this is an FCC-488 JDSU Laser unit and I obtained a printed manual to confirm this. We have tested this unit to power up but we cannot get the laser ready LED to illuminate. There are no accessories other than what are shown in the pictures. There is a printed 51 page manual included. Please see the pictures for all details and for what is included in this sale.


Another eBay keyword here: AS-IS. This also translates directly to the word above.

Broken.

Well, it was at $55 and had a few hours left. I figured, what the heck, I'll put in a super lowball bid of around $80. Free shipping; worst case, I get some fiber out of the deal and maybe some IR diodes. But I saw this shot in the auction's photos:



And thought to myself... Well.. Maybe. JUST MAYBE, this thing might not be broken. It had a data port in the back - and the guy testing it was just jamming a paperclip into the interlock pins (1-3, as specified in the manual he had found and included.) Owing to my past experience with the Novalux 488 DPSS, which ultimately lead to some help from Trevor (further explained in that thread) -- I knew there was a possibility that this thing had an RS-232 interface and could take commands from the computer. What if this guy was missing something?

Well, again, I put in $80, feeling like I was prrrrobably going to lose that money. Because it basically said all over the place that it was BROKEN, there were only 2 bids other than mine. A few hours passed and, what do you know: I won it for $76.05 -- shipping included. Five cents over the next highest bidder... At first, I actually felt a little sick, since I knew (probably) that this thing was going to be a paperweight. Oh well, you live and you learn, right?

Well, today it arrived. On top was the inkjet-printed manual that the guy had managed to find:



CW, frequency doubled 488nm solid state laser. If only.

The laser itself:



That was it. Nothing else. The manual and the unit. Scratched up a bit, "Firmware 2.11" labeled on it with scotch tape over it...

In the back, I saw the power connection, (5v DC, 4A; the only pins used are the bottom left and middle left, with the bottom left being positive..) and the excellent "paperclip interlock" installed.



By the way, an interesting side note. I did open the unit up at first, and unscrewed the fiber coupling to try to tighten it (as it was loose.) -- The interesting things I found out:

  • It includes TWO 'butterfly' packaged diodes, each attached to a fiber strand.
  • The two outgoing IR fiber strands lead all the way up to the laser head.
  • The frequency doubling appears to occur inside the attachment at the end of the fiber run! Meaning, the doubling happens in the 'tip' of the fiber device, NOT in the body of the laser.
  • There's also a third 'plastic' fiber strand that runs back to the housing, which appears to be used for output monitoring.

I thought this was pretty interesting. The doubling doesn't appear to happen in the 'box' at all, it seems to happen at the end of the 'fiber cable'. Kind of cool.

Upon powering it up with the "paperclip interlock" installed, I got the exact same result the seller got -- one green light (controller status) and one 'off' light (laser status). But, I thought, the laser status LED wasn't showing an error, the manual said that this would be red. I figured if the laser was actually broken, it'd be showing an error on the laser and the controller. The controller was showing green, and the laser was simply showing "off". This was encouraging.

The paperclip really wasn't my style. And I really wanted to try to issue some commands to the laser which were listed in the manual. So, I quickly soldered together a cable by cannibalizing an old DB15 VGA cable and hacking off the end of an old DB9 serial cable.



I installed the "interlock" permanently across pins 1-3 of the DB15, and routed the TXD, RXD and GND pins from pins 2,3 and 5 of the DB9 serial to pins 4,6 and 10 of the DB15.



To be able to address this thing (hopefully) on a modern system, I used a USB to Serial converter. Windows 7 recognized it right away and I used the free terminal program Putty (which - unknown to many actually supports serial ports up to 'com-whatever', its a million times better than Hyperterminal) -- to get the serial interface going.



I connected everything up, and after hitting enter a few times I noticed the laser ready light was green. Well, hot damn.



I entered a few commands in Putty, one of them was a status command which returned the current values that the laser was set to or returning. I queried the power, and it returned "2.2mA" -- obviously not enough to get the thing lasing, and probably (hopefully?) why I wasn't seeing output.



Moment of truth, I issued the command "LON", for Laser On... The Laser status LED blinked Yellow, Green, Yellow, Green... Damn. Error, I thought. But I looked at the manual. This meant "warmup stage".

Ok, wait a little bit..

And a little bit more...

And then.



Blammo. Bright, sweet 488nm photons. Collimated, too. I couldn't believe it. This $76 off-chance crapshoot was putting out a VERY bright cyan beam.

Hot damn.

And, as I said, collimated, too. I was NOT expecting that from a fiber coupled laser. The divergence on this thing is tight. Pretty much no noticeable divergence at 10 feet:



So, it was time to measure the power:



The laser seems to go through a 'warmup calibration' phase where it does 10mW for about 30 seconds, then 5mW for about 10 seconds, and then does 25mW solid, unwavering, completely flat, for the remainder.



That "remainder" for me so far has been 7-8 minutes without any power dip or problem whatseover. Just 25mW of solid state 488, all the time. This thing is MUCH brighter by FAR than my Novalux DPSS. And stable, and cool; it seems to require only moderate heatsinking. (Putting it on a large metal block seems to keep the entire thing lukewarm to the touch, and again, I've gone 7-8 minutes with no porblems in the solid 25mW of power.)

So...

I'm not sure if there's a moral to this or not. Most of the time when you're taking chances on eBay you're going to get screwed. This time, miraculously, the thing worked. There's always a chance that people just haven't tried everything, I guess... For me this was an amazing gamble that paid off... I have no idea how much this would go for as "working", but I know I've seen the Coherent Sapphire 20-40mW units go for $300-$500 in an unknown state of repair.

Anyways, I know I haven't been around LPF much lately (due to RL circumstances being pretty rough) - but this was a hell of a way to come back around.
 
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What did you search to get that result (in ebay?) Also, you are a lucky [CENSORED] I cannot believe what I am seeing.......What would be the cost of getting an equivalent system from CNI or directly from the source? Incredibly jealous as of now, you better update your sig again...
 

aryntha

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Bloompyle,

I do pretty much nightly searches for:

"JDSU Laser"
"Uniphase Laser"
"Melles Griot Laser"
"HeNe Laser"
"488nm Laser"
"Cyan Laser"
"612nm Laser"
"Orange Laser"

Then I sort by most recently listed. That's my "secret", heh. So something like this, I'd see it right when it was listed.

From what I've been able to tell, from JDSU, new, or from CNI, we're talking ~$4000+, for 25mW.

And... trust me, it took me a while to believe it too. Again,I've had to go through a LOT of failures to reach this success. I've probably lost $2000 or more on bad auctions. So you have to kind of go into it knowing it's a gamble. Kind of like: if you're going to go to Vegas, realize that the money you're putting down is what you're going to lose.

If you don't lose it all, then that's just a bonus.
 
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Bloompyle,

I do pretty much nightly searches for:

"JDSU Laser"
"Uniphase Laser"
"Melles Griot Laser"
"HeNe Laser"
"488nm Laser"
"Cyan Laser"
"612nm Laser"
"Orange Laser"

Then I sort by most recently listed. That's my "secret", heh. So something like this, I'd see it right when it was listed.

From what I've been able to tell, from JDSU, new, or from CNI, we're talking ~$4000+, for 25mW.

And... trust me, it took me a while to believe it too. Again,I've had to go through a LOT of failures to reach this success. I've probably lost $2000 or more on bad auctions. So you have to kind of go into it knowing it's a gamble. Kind of like: if you're going to go to Vegas, realize that the money you're putting down is what you're going to lose.

If you don't lose it all, then that's just a bonus.
I'll give similar tactics a shot, but now you have competition ;)

And you got it for $76 and change?!?! That's like getting a 593.5 for $5. Epic find sir :beer:
 

AnthoT

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Wow talk about luck! Anyway congrats on the great price 488nm laser hopefully it lasts you awhile :beer:

-Anthony
 
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lazeerer

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First the Hene Now This. Give me some of that Luck.:p

Ive been looking into those 488nm on ebay for a wail now but never pulled the trigger on any of them. I ended up buying a Coherent Cube instead. Iam going to keep a Look Out. You and rhd both Scored On these 488nm.

Nice Job Buddy.:)
 
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DJNY

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That was a very interesting read!

I´m glad you were lucky this time :)

Great work!


Lazeerer might be able to super-polish this thing :D
 
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vk2fro

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nice work aryntha - thats a lot of 488nm without the big fans and psu's. Its pretty cool that all the action happens in the fibre head and not in the laser box :)
 

Bluefan

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I saw that one on ebay, if I wasn't in the middle of a move I would have placed a bid on it. But considering argons give the same wavelength and these usually go expensive I didn't bother. So, congratulations to you! Maybe someday later I'll catch a 488nm solid state.
 

Lonewolf

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Yeah, some people are gonna be angry at me for lucking out like this...

A discliamer first, I rarely "luck out". As some vets here can attest to, I've had more ebay losses than wins. I have a pile of "dead soldiers" I chalked up to a loss, and the 'tuition price for learning'. ArIons, HeNes, DPSS, you name it, i've blown a deal on a dead one, or been taken for a ride.

Congrats on your score :) although I'm not a vet, I've read some of your purchases from the nightmare collection. I'm always happy to see good people win!

The ones that get angry have issues :tinfoil:
 

532 with Envy

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Glad to see someone here got this unit! If I remember correctly you made out with a pretty good price on it, but like you said....many times you end up getting something that doesn't work.

Congratulations!
 

LtKernelPanic

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I hate you! :eg:

Seriously though nice find. 488 is such a beautiful wavelength. I usually run my ML Argon at around 5.5A for its monthly burn but I always have to ramp it up to 9-10A for a minute or two just to enjoy the full 100+mw of 488 goodness. The individual lines look pretty damned sweet too. Now if you'll excuse me I need to go get my 488nm fix! *









*(thanks for the "reminder". I was going to fire the argon up this past weekend and never got around to it.)
 
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I've never seen an auction off eBay won over a nickle before. Its usually $1, or at the very least $0.25.

Never apologize for getting a good deal. Thats silly.

Nice score though.
 
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