/diy/ - Do It Yourself

well, it depends. That large board seems to have lots of eg MC3403 opamps.. Those could be useful, they are fairly generic parts. But on the other hand, you can get new ones for like 70 cents, so is taking those apart really worth your time? Especially if you factor in the fact that some of those chips maybe borked from old age or the removal process.

Additionally when you buy new parts, you can pick the ones which are best suited specifically for the project you are putting them into, instead of using whatever you happen to find in your junk.

Seeing that most of the parts are through-hole, that maybe another thing to note. World is transitioning to surface-mount parts, making PCBs for those is lot easier because you don't need to drill anything.

allaboutcircuits.com seems to the most recommended
there might be others listed here
http://fourchandiy.com/w/index.php/Recommended_Reading

ICs aren't really worth the trouble because they're difficult to unsolder and inexpensive.
Old boards are pretty handy though, especially if you need a component now.

Use a heat gun. mass flow the solder, tap it on a table, shit should mostly fall out on it's own. I can't throw away boards and shit, I always salvage them, and I use the random shit on a fairly frequent basis. It's not about money. It's about time, parts on hand, and not wanting perfectly good shit to go to a dump.

if you are going to salvage parts, you probably want some quick way to identify them, like the rule of thumb that 74-series and 4000 series are basic logic etc.

resistors have color codes, caps have their values often written on them. although caps also have the most limited lifetimes, so salvaging those might not be such a good idea.

just having a huge bin of random parts is no use if you don't know what you have, and have some hope of finding the parts too when you need them.

Are you new to English because your grammar and sentence structure are horrendous.

>>397135
Would a hair dryer work as a heat gun? Serious question

>>397163
Does your hair drier do 700 degrees plus?

>>397178
Is that Celsius or Fahrenheit?

>>397179
in a weird coincidence... either. High end guns do 700C at the very top of their range and low end guns do atleast 700F.

>>397135
using a heat gun to desolder is a bad idea,
with lack of experience you will just end up melting the components

>>397199

Lol, I occasionally use a blowtorch. Not on anything I *really* want, but still.

years ago I had a friend who worked with electronics a lot more than I do. I was promoted to a supervisory position overseeing projects worked on by others, and didn't get much hands on, while he was in research and development, and basically paid to experiment all day. Part of his job was to adapt one thing or other to a different purpose than it was originally designed for... such as sticking PCI based devices into VME machines. A lot of equipment was thrown at him, saying "here, make these compatible" so he acquired quite a collection of parts boards, and machines of all kinds. after ordering some of the same components over and over again, he thought. I've already got these parts in all these prototype boards, etc. so he decided to inventory all his spare boards so he wouldn't have to wait on an order for something he already had. Mind you nothing he made was a finished product, we didn't put used parts in anything we sold, he just did development, prototyped, and tested, so most of these components were barely used and just setting. Excluding breakthrough developments where the piece had significant historical value, which were preserved.

The team assigned to inventory the components on the boards were young inexperienced kids who learned a lot from looking up the components and entering them into a database. With some components costing as much as $7K each, his re-utilization plan saved the company hundreds of thousands of dollars.
I'm not implying that you're sitting on a goldmine, I'm simply saying if you have the space to store them, and you intend to tinker, you could benefit from knowing what you have on hand.

>>397212
A single component costing 7k?
Could you give me an example? I am seriously curious as I thought the most expensive stuff on a board could be around 100$, tops.

Was it some sort of particle detector?

>>397223
there are lots of expensive parts once you get out of the lowest-cost consumer market.

example: a piece of test equipment i use has a $500 fpga in it. in addition, asic prototypes use high end fpgas because it's cheaper to develop and work out bugs on a $50k fpga than to keep spinning silicon through the fab.

before you throw any boards away,
cut these little things off, (pic related)
and save them until you get enough to sell

they can be small or large, and only take a second to snip off. They get processed to recover the Tantalum they contain, and you can make some money selling them if you have enough.
Not all capacitors contain tantalum, only a few, but for example the big orange one on the far right in the OP pic.

>>397230
This is hard man, don't think you won't need to hit the books.

>>397223

Bigger FPGAs can cost that much or even more. Check Altera's web shop, if you're interested.

Other possibilities:
space-certified shit, including space fpgas
scope adcs
big vacuum tubes
exotic sensors

>>397223
I'm not at liberty to disclose that information. Not to say that government spending is crazy, i'll put it simply. Millions of dollars can go into designing a chip. If they are intended for consumer use, that cost is recaptured by selling millions of copies. But when the chip is specialized and custom made for a limited production, It still cost the same, and often more to develop, but in these cases the cost is divided by much fewer units sold.

But even in consumer components, CPUs for one, far exceed your $100 tops.

>>397243
>>397238
>>397228

Alright, FPGAs and ASICs make sense.
I somehow forgot about them, just thought that spending 7k on a simple resistor, capacitor or similar primitives seemed a little expensive.

>>397135
The same thought

>>397145
Sorry, im from Valencia Spain, im trying to improve my english

>>397212
I have begun to clasify all the components I find, theres a lot of scrap in my garage from old computers, hard drives, I even have an zx spectrum

Thanks for the help guys!

hey, i wonder where i could learn all about circuits?
>http://www.allaboutcircuits.com/