can any of these transistors be used ?

found these transistors off an old VHS player and just wanted to know if it was possible to use these for arduino,

can i use any of these transistors for say wiring up a speaker to a arduino mega 2560 for music playing or .wav file play back to the speaker?

any advice would help... i have no idea if these are even compatible with the wiring of a speaker to an arduino...

if they are... how big of a speaker can i wire them up too?

http://www.instructables.com/id/Playing-Wave-file-using-arduino/

They may not be transistors. I don’t recognise any of the numbers as transistors.

L5431 is probably a shunt voltage regulator. I don't recognize any others.

what about these...

i seen people say go with this... BC546B or BC546: http://www.ebay.com/itm/220756135095?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

and some say go with BC549C NPN...

does it matter or is one better then the other? not sure... would like some advice tho

bryanmc1988: what about these...

The "B" or "C" at the end is a gain category for the "BC" series (not that old :D ).

Just look up datasheets, just about any will probably do for simple projects such as controlling small LEDs.

It is barely worth your while nowadays using "pulls".

L5431

C3331

A1318: SEE ATTACHED

@polymorph,
Thanks for the WAV file project link ! I think I’ll give that a go…

A1318-A1319-Datasheet (2).pdf (835 KB)

combined, they amount to about $1.00 worth of parts.

it is easy to get lots and lots of pulls.

outside in the fresh air take a brick, a large box like a pizza box and some aluminum foil place the aluminum foil to the box and put the brick on it.

while wearing safety glasses and heavy leather gloves, use your blow torch to warm up the board. as it gets hotter the lead will begin to melt.

sharply snap the board, lead side down, parts up.... on the brick.

the lead will fly off onto the aluminum. the loose chips will fly every way.

you can easily salvage $1.00 or even $1.50 in parts.

I used to have access to old modems, with tiny relays. loads of fun

I've used the same method but I would describe it this way:

Using the safety gear mentioned, select the component you wish to extract and place a pair of needle-nose pliers or IC chip puller on the device. Direct the blowtorch flame at the solder (not lead) on the PCB. Depending on how hot the flame is , the solder should flow almost immediately and you should be able to pull the component through hole leads out of the PCB within a couple of seconds. As soon as the component come loose and you have it completely out of the board direct the flame away from the pcb. By always using the least amount of heat, for the shortest period of time , you should be able to recover almost all the components without damaging them.

sharply snap the board, lead side down, parts up.... on the brick.

What he is saying is that after running the torch flame back and forth for a couple of seconds on the back side (solder side) of the board, the solder starts to flow and the sharp impact on the brick (Solid steel works too) causing the molten solder to fly out of the holes making it easy to extract the components. You can cherry pick one device at a time if you want or just shotgun it and do a whole bank of chips. The sharp rapping on a solid surface is a very common desoldering technique used by thousands of techs every day. It takes 2 seconds. Normal desoldering with solder wick takes minutes.

These are japanese transistors (pretty much all consumer electronics uses japanese transistors).

You have to know the JEDEC numbering scheme to make sense of the part numbers.

Bipolar transistors start 2SA, 2SB, 2SC, 2SD, MOSFETs start 2SJ or 2SK. The 2 is the lead count minus one. The S means silicon The A/B/C/D/J/K/etc says what kind of device - google jedec part numbering for more details.

These days the "2S" is left off as it can be assumed since (nearly) all devices are silicon and you can count the leads!

Anyway 2SA1318 is PNP, 50V, 200mA, gain >= 100, gain-bandwidth product 200MHz 2SC3331 is NPN, 50V, 200mA, gain >= 100, gain-bandwidth product 200MHz

(these are complementary pair).

2SD734 is NPN, audio amp, 20V, 0.7A, 0.6W

The L431 appears to be a 2.5V shunt regulator (like a zener but better).

I will not describe how I have, in the past liberated electronic components for fear of being criticised for lack of health and safety procedure....

But it was quicker and warmer than those described above... :)

Not thermite?

MarkT: Not thermite?

No, haven't made any yet though I have made lots and lots of iron filings and aluminium swarf....

It involved a gas cooker, with a very large uncovered flame (can't do that now, safety interlocks in the cooker) ... and stuff.

raschemmel: You can cherry pick one device at a time if you want or just shotgun it and do a whole bank of chips. The sharp rapping on a solid surface is a very common desoldering technique used by thousands of techs every day. It takes 2 seconds. Normal desoldering with solder wick takes minutes.

I find that there is a magical temperature, just as the board starts to change color, but before the smoke starts to billow. the sharp rap frees the solder and the chips bounce off. I have had a few chips that I got confused with new parts. for me the leads being free some excess solder is a plus. I guess these days one could make an 'oven' with bricks and a thermocouple and be more scientific.

dave-in-nj: I guess these days one could make an 'oven' with bricks and a thermocouple and be more scientific.

And where exactly is the fun in that? ;)