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Components Source: from old computer parts?

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I was disassembling an old Pentium III POS computer with a dead PSU last night when it hit me:

I see all these capacitors and resistors on the boards from modems, network cards, power supply units, old school VGA boards, even the motherboard....

Does anyone else desolder these components and use them in their projects? Are they ever usable in laser projects, like in drivers?

Just on the motherboard, I noticed a bunch of little cylindrical capacitors (markings indicated):

SMS 16V 10uF
SHL 16V 220uF
LXV 10V 1500uF
SMS 16V 22uF
SXE 16V 120uF

and I also noticed a few things that look very similar to the LM317:

SC EZ1585CM 0002 G19218A1
i 76129S H001 A4K

Should I desolder and harvest these components, or do they serve no purpose in the laser hobby?

Thanks for letting me know.
 

Eudaimonium

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It is unlikely that you will find some laser-related IC chips, however,
All the SMD capacitors and resistors ALWAYS come in handy.

I found exeptional amount of good components in DVD drive electronics alone.
 

MarioMaster

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Electronic components are always useful, it's all whether or not you want to spend the time to salvage the components from it or not. Usually I don't save boards unless they have several useful components but I've already got a box full of boards to scrounge components from. I also do a lot more electronics work than just lasers though...

TLDR version - only if you want to bother desoldering them
 

photonaholic

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One thing to consider, electrolytic capacitors do dry out, then the values change sometimes dramatically.

By the time most motherboards are laid to rest, many of the caps have already swollen from stress.

look closely at the caps, if the tops are even slightly "domed" on top, it's not worth it to salvage them.

In my personal experiences, if I am fabricating a complex circuit from the ground up, I will use as many virgin components as I can, troubleshooting after building is tiresome and frustrating.

Not to mention, desoldering from these new quad layer boards is a real pain in the arse.
 
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One thing to consider, electrolytic capacitors do dry out, then the values change sometimes dramatically.

By the time most motherboards are laid to rest, many of the caps have already swollen from stress.

look closely at the caps, if the tops are even slightly "domed" on top, it's not worth it to salvage them.

In my personal experiences, if I am fabricating a complex circuit from the ground up, I will use as many virgin components as I can, troubleshooting after building is tiresome and frustrating.

Not to mention, desoldering from these new quad layer boards is a real pain in the arse.
You must holding your mouth wrong, Wayne, I never seem to have any trouble with the QL PCB's:D
 

IceNoise

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By the time most motherboards are laid to rest, many of the caps have already swollen from stress.

look closely at the caps, if the tops are even slightly "domed" on top, it's not worth it to salvage them.
Kinda off topic, But I acually had a mates motherboard with swollen, or bulging Caps. yellow stuff leaking from then amd everything. every one of the same value was in the same condition, But the others were OK.

Aparrently what happened was an incomplete recipie for the electrolite stuff inside got out by accedent, and was snatched up by a chinese manufacturer. who made probablly millions of these caps. A gas is produced inside the cap causing them to expand, and sometimes POP!! These were around during the Athlon XP era in the PC world I am guessing.

Most caps won't do this, But Im sure that after years of use, the values can change somewhat.

Sorry Photon, just thought I'd let you know where these 'swollern' caps came from...

I think that if you're in a fix and EED the resistor off the motherboard, go for it, but components are so damn cheap these days, it makes sense to use new components. I can get an LM317t for less than 50p in maplins electronics. (UK electonics store.)

Si
 
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This remembers me of the day I tried to use the car charger for my mobile as DC transformer to driver a laser module. Somehow, I thought They needed 24V in, and when I connected to the PSU the damn capacitor literally exploded kicking my hand so hard, I had the mark for months!
 

photonaholic

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You must holding your mouth wrong, Wayne, I never seem to have any trouble with the QL PCB's:D

Desoldering station number one $250, Desodering station number two $185, SMD removal tool, $149.99, saving 15 cents on a capacitor.... Priceless!
 
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Desoldering station number one $250, Desodering station number two $185, SMD removal tool, $149.99, saving 15 cents on a capacitor.... Priceless!
ROTFL Yes, I never have thought of it that way. The components I'm scrapping now cost me >$3 a piece. LOL.
 

Eudaimonium

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ROTFL Yes, I never have thought of it that way. The components I'm scrapping now cost me >$3 a piece. LOL.
It is much easier to desolder a component offa board and save yourself the trouble of driving to electronics shop and buying it (or ordering online and waiting for it).

Man, I envy you of your soldering and rework stations.
Saves unbelivable amount of times when desoldering multi-pin SMD ICs.

You don't even need soldering wick with all that equipment!:wave:
 
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What is "soldering wick"?:) I forgot about that awful stuff. (burns the h#ll out of your components)
A Desoldering and Rework station is one of those things that once you use, you think "How did I ever do anything without this tool"
I can completely strip a mother board or TV PCB in <10 minutes.:D
If you get a LD soldered crooked on your driver,pssh! pssh!, removed, that quick, along with all traces of solder on the LD and the driver.(suction is, 29.92" of vacuum @200microns, about 100 X greater then a good shop vac)

BTW: To anybody considering buying one of these; Don't cheap-out, buy a Hakko, it has the best specs, by far, of other ones. Over 250 different tips available, on E-bay for $2-5 each, for the most common ones. Other brands tips can cost up to $30 each
 
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Eudaimonium

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Wow!

Well, I can't imagine desoldering something (multi pin IC) without wick right now, I used it couple of times but never had it actually, so I am gettign some from DX (should be in one of those packages that arrived back home).
Simple desolder pump works good for me.
But that is mighty equipement...
 




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