Help with harvesting parts

[davey696]

hi,
I am currently going through all my dud electronic equioment with my soldering iron and a bright idea to make my build cheaper by using parts i can "harvest" from them, however past the capacitors and momentary switches is there anything else salvagable? if i get an aixiz housing would the laser in my cd drive actually be powerful enough to burn anything?also there is quite a feww potentiometers on there, how do identify whether they will work or not?
Thanks for your help in advance,
Dave
P.s i put this in general because i wasn't sure where else to put it if its in the wrong place let me know and i'll see if i can change it.

edit
Right i've done abit more research into everything, i think that i am right in saying that the main thing to keep a ld alive is to regulate the current and to also make sure that it doesn't take a voltage spike when first powering up.
With the electronics knowledge i have(not loads) i have worked out that i need around a 10 ohm resistor to give about 125 out and i know that capacitors just need to be double the maximum voltage on the circuit to protect well, if anyone is/does read this could you please let me know if i am correct.

 

[billg519]

Salvage is a very good way to build a stock of components. Some types of boards will be better than others. The board from a crt monitor or crt tv is a great source for capacitors, current sense resistors, mosfets, diodes, rectifiers, pots, transistors and inductors. Computer power supplies contain useful components, or if working, can be made into a bench PS for experiments. Get a good DMM to test resistors, pots, diodes, caps, etc.

As far as laser salvage from CD or DVD devices goes, the diode will only burn if it comes from a burner. Players have a weak 5mW diode only useful for practicing extraction from the sled. A high speed CD burner will have an IR LD in it capable of burning. A DVD burner will of course have a red diode in it as well as an IR diode for reading and burning CD's.

You must be referring to the DDL (LM317) current regulator and want an output current of 125mA? This would be a 10 ohm resistor needed, yes. Capacitors have a voltage rating, but also must be of the correct value of capacitance in uf. An output cap for the LM317 could be 10-47uf at 16V or better. Always short this cap before connecting the LD. Legions of LD's have died needlessly from this cap not being shorted prior to connecting the LD. The capacitive discharge will kill an LD.

 

[davey696]

thanks for the information, i currently have a sandwich bag full of parts from car stereos(caps,pots and a heap of resistors) i also have a load of voltage regulators but the only thing is i don't know how to find out how much they let through,i'm going to invest in a dmm over the next day or so.
Thanks again,
Dave

 

[Morgan]

Hey Dave,

If you can get any identification numbers from your harvested components then you can usually pull up some datasheets from the internet. This should give you the info you require to make use of them.

M

 

[billg519]

You can look up these semiconductors on the web.

ALLDATASHEET.COM - Datasheet search site, Datasheet search site for Electronic Components and Semiconductors and other semiconductors.
Datasheet & Application Note Database, PDF, Circuits, Datasheets | Datasheet Archive
Datasheet - World Electronic Components Datasheets Search Site!

 

[joekane]

Lots of great information here. I've got a stack of "junk" electronics and I've been wanting to do a project like this for a while anyway.

 

[davey696]

thanks guys, yuo kmow what i can't believe it didn't occur to me to search google to start off with, ill get on with that today,
I'll let yuo know how i get on.
Just ordered a 200mw red pointer with goggles from o-like any idea how long they take to deliver? it doesn't say on their site.
Thanks,
Dave