partspartsparts

[PKV]

Has anyone had any luck pulling parts from old circuit boards? And if you have, what sort of devices give the best yield of compatible parts?

[sir_modulus]

Desoldering braid, SolderVac and a good soldering iron. The soldervac (vaccum desoldering pump...usually about $10) is an easy way to get off blobs of solder quick and without eating through solder braid (it's damn expensive normally...), and the braid'll get of the rest. That's gonna be your best best.

[sfr]

I've heard of folks using a heat gun on the back side of the board, which heats the solder enough to let many parts just fall out.  I've never tried it.

Honestly, I don't salvage many parts any more.  Too many times I've had a build messed up by an electrolytic cap that's gone bad, flaky salvage wire (that's usually too big to get into PCB holes or too small to strip easily) or IC's that were fried when something got shorted (which was why the electronics where getting tossed in the first place).  Resistors and caps often have leads that are too short to use, anyway.  For the cost of my time salvaging parts, I find it's just as cost-effective to order the bulk packs from Futurlec or something when it comes to caps and resistors and diodes.  IC's and trasistors are pretty cheap too, and I've still got a drawer full of old ones from salvaging that I never bothered using, because I don't know exactly what they are, (and I'm too lazy to spend an afternoon punching in part numbers into Mouser to see what they are)  I do know I have a bunch of quad op amps, which would be handy except they're a pain in the ass to design around.

The few things I still always take the time to salvage are pots, knobs, transformers, nuts and washers, the occasional jack (most of the ones you find are board mounted, but if they're on a daughter board, that's often just as good as panel mount)  and depending on the size and construction of it, the enclosure.  Sometimes you'll find a stereo with a daughter board for powersupply filtering that can often work well as a good regulated, bi-polar power supply.

If I'm going to go the trouble of gutting something, however, I usually save the board in a box, so if I find myself one cap short of finishing a project, I can hunt over a couple of boards and see if I can find what I need.

[tcobretti]

Germanium transistors!  Just be sure to heat sink 'em.

[RickL]

I've used a heat gun to desolder salvaged boards quite successfully. The parts don't always fall out (although sometimes a good whack on the board after the solder has been heated enough will knock most of them out) but they can usually be pulled out quite easily with a pair of pliers.

I mostly agree with SFR about what parts you can use except I've had quite good luck with salvaged electrolytic capacitors. Most of the diodes I use are salvaged. I also use salvaged transistors fairly frequently. Many projects just need generic NPN or PNP transistors and almost anything will work. I've also found single and dual op-amps that I've used where I'm not too concerned about noise. I use salvaged caps too and they're particularly nice to have around when you need just one slightly weird value like a 0.0018uF or such. I have more DIP switches than I know what to do with from salvaged boards. I've also lucked into optoisolators and inductors (what am I going to do with a 2 H inductor?) occasionally.

Old home organs are a goldmine for salvaged parts as are old stereos and TVs. It's also worth checking at your local scrap yard if you have one. Many of them have a bin with old boards in them that you can pick through. You'll get charged for the ones you take but sometimes you'll hit the jackpot. I got over 300 enclosed 1/4 inch jacks off boards I found in a bin once. I didn't have to buy another jack for a couple of years.

[zyxwyvu]

I've salvaged some parts from a few things, the best of which was an old phone - I must have taken about 20 electrolytic caps off of it. Some other good places to look are old computer cards like IDE/SCSI hard drive controllers, network cards and modems. I don't have any desoldering braid or a vacuum, so what I do is melt the solder with my iron and then slam the board on a table. The solder comes right off if you do it fast enough! If that doesn't work, you can grab the component with pliers, and pull out each end while you melt the solder for the pin.

[Barcode80]

speaking of salvaged parts, i mentioned this in another thread and maybe u guys can shed some light. i salvaged some pcb mount jacks and i can't determine a pinout. i know the front pin is ground, but i can't figure out which of the other two is ring and which is sleeve. here is a pic.




they are in brand new shape pulled from a brand new (but DOA) zoom multieffect that came in at the shop i work at. which do you guys think is which pin?

[PKV]

I'm going to guess tip toward jack end, and ring on the same side opposite end, with sleeve next to it. do you know if it was the in or out jack?

[Barcode80]

i know the singular pin near my thumb in the pic (or near the jack opening) is sleeve, as it is one piece with the threaded jack receptacle, which would be grounded against the enclosure. so the two back pins are the ones i can't decide which is which on.

also, that pin is centered at the jack end. so neither of the other pins are "on the same side"

[alderbody]

i salvaged some pcb mount jacks and i can't determine a pinout

plug in a guitar cable.

With your DMM, check the continuity between the leads of your jack and the plug on the other side of the cable.

This way you can determine which is tip and which is sleeve/ring.

[MikeH]

I use a desoldering iron from radioshack (about 10 bucks).  They're pretty high wattage, around 45watts, I think.  But they work so quickly I've never had a problem ruining components.  And they come out really clean too.  You can also use it with one hand, which is nice.  They're also handy for when you muck up a solder when installing parts and want to re-solder it. 

As far as parts, I've had luck with phones, CD players, VCRs, and computers.  But the mother load was in an old audio amplifier/speaker phone type deal laying around at my work.  It looked like it was from the 60's.  All kinds of old transistors and good stuff.

[Chuck]

Back in the early 80s, I lived in Japan and I was a very poor enlisted Marine.
I would get old TVs from the back of the Japanese tv stores and I salvaged tons of parts with just a soldering iron and tissue paper.
I also learned to fix TVs.  Back then they'd have the schematics pasted inside the back cover.
But I had to learn to read some kanji to read the print on the schematics.  I did that by comparing the characters to a kanji/english dictionary.  Long proces at first -- until you start to learn the characters.
I ended up fixing a tv or so a week - which I sold to other guys for $50 each.

I did have a lot of time on my hands. 

[Mark Hammer]

Older (8-bit and some early 16-bit) sound cards have a surprisingly wide array of usable parts on them.  There are many smaller-package electrolytics that are quite reusable and have enough lead length left on them for re-use in PCBs.  Some older cards will come with a variety of dual or quad op-amps (I have a Soundblaster that yielded a couple of TL074s).  Older sound cards will also often come with onboard power-amp chips, often stereo chips that are easily bridged to mono for more power.  The TDA1517 (used in Paul Nelson's stereo guitar amp project) was often used in sound cards, as were the TEA2025 and several other 14-pin dip forms, and the venerable LM386.

A word about using heat guns to remove parts.  It "works" but those boards get VERY hot.  If you use this, you will want to grip the board with a vice or vice grip pliers.  You do NOT want the board to flip and fall on your lap or touch your hand.  As well, if the board has tiny SMT resistors, get ready for the shower of little tiny bits on your benchtop.

[The Tone God]

To add when desoldering boards with a heat gun wear a respirator. Besides lead potentially becoming air born the board material can sometimes release other bad chemicals in the air. Also disconnect your nearby fire alarms as many will sense those chemicals and go off. Hmm makes you wonder if the fire alarm is configured to sense those chemicals maybe they are really bad for you.

To be honest I don't support the heat gun method. Besides the above safety concerns most of the parts we use are through hole. Trying yank parts out while the board is hot and solder is molten is annoying and even dangerous not too mention the high potential risk of damaging the parts due to overheat.

I would also add that using some parts, even if they look good, off of old boards are not worth the trouble they could cause. An example would be electrolytic caps. They have only a certain lifetime and when you are re-using caps that are already old you are loosing right out of the gate especially for the cheap cost they are these days. Not worth the time IMHO.

About the only thing I keep an eye out for in old gear is Ges which I usually find in old radios. Just about everything else I can get new and fresh through suppliers.

Andrew

[PKV]

Thanks to everyone for the responses - truth here is, since discovering (after nearly 29 years of playing guitar) the potential joy of DIY, I have been dying to build something. And alternative sources for parts are a good idea at the moment, if you catch my drift...but while we're on the subject, where does everyone get their stuff from?

thanks again

[zpyder]

where does everyone get their stuff from?

I get my stuff from 4 main sources at this point:
Mouser.com - HUGE selection of components for cheap.  Very low prices.  You can get resistors for 3 cents here.  Fast shipping
Futurlec.com - I buy potentiometers and knobs from them.  Easy to navigate site.  Also look at their value packs for great grab bags!
Here!  Click the STORE link above - I like buying 3PDT switches, jacks, perfboard from Aron.  Also has Ge trannies.  Lightning shipping!
Small Bear - smallbearelec.com is an online store dedicated to DIY fx projects.  Basically has gathered and stocked all the best parts!

cheers,
zpyder

[RickL]

I get most of my parts from three places. Small Bear (which you're going to see mentioned alot), a local electronics store in Victoria called Queale Electronics and a wonderful store in Vancouver called Lee Electronics. I rarely leave Lee without at least $80 worth of pots, caps, ICs and transistors.

[col]

I have had good experiences retrieving items off scrap boards using a solder sucker. They usually just drop out once the solder is removed. Older items are usually the best as modern equipment is usually sm. I have posted anothe rthread on using items from low energy light bulbs. All the components are 'real' and useful. Loads of diodes and caps, two transistors etc.

Col

[alderbody]

For EU DIYers, Banzai is an excellent choice!

They ship wordwide, too.

http://www.banzaieffects.com