Very simple speaker circuit

[Octember13]

Hey all. So I'm a total beginner to everything having to do with electronics. To the point where i'm still not quite sure exactly what resistors do. Regardless, i've been having loads of fun going to the dump and picking up old computers and such, taking them apart (I learned the hard way the hazards.) and messing with the little pieces that I know how to work with. So far, all i've really been making are super simple circuits, with two AA batteries, a bunch of switches, and a few LED's.

While taking apart the computer, I found and removed a small speaker. I became curious about how to make it project sound, so I hooked it up with 3 volts, and heard a little popping sound whenever I switched it on or off. This amused me for about five minutes, but I really wanted it to do more than just pop. How would you use the speaker to make any kind of noise? For instance, if I wanted to make a buzzing kind of sound, how would that work? Is there a special kind of speaker that buzzes when you run power through it? Let me know. Any advice from people who know what they're doing would be greatly appreciated. Thanks.

[StayatHomeElectronics]

They do make piezo buzzers that just need to be connected to batteries and they, well, buzz.

They carry them at Radio Shack if you are in the US.

http://www.radioshack.com/product/in...ductId=2062394

You can probably find them at most electronics supply places on the web.

[Octember13]

How, though, would you make a speaker make sound? What's different about the electricity flowing to the speakers than to that buzzer?

[tibbles]

hi octember
if you were able to connect and disconnect your battery a few thousand times a second you would set up an audio tone in your speaker,
normally we let electronics do this, in this instance an audio oscillator,
the buzzer sahe mentions i think has internal circuitry to produce this.
plenty of these circuits on aac.

but if your just starting what about this

http://www.hwscience.com/physics/electronics/Experiment9.pdf
dougal

[tibbles]

ps you may need adobe reader to view pic. usually a free download (img .c/right ?)

r2 can be varied to change tone,

i think i can speak for my fellow insomniacs,there is always plenty of help here.
dougal

[Octember13]

Looks pretty do-able. Once that's made, would it make a certain pitch? Would the pitch be adjusted by changing the resistors? Don't mean to be a hassle, just curious here.

[BMorse]

You could replace the resistor with a variable one (potentiometer) then you can change the pitch by just turning it one way or the other, almost like a volume control except it doesn't change the volume only the pitch...


My .02

[Octember13]

Huh. Thanks for the input, everyone. How would you change the volume? By increasing/lowering the ampage?

[auri_z]

Originally Posted by Octember13

Huh. Thanks for the input, everyone. How would you change the volume? By increasing/lowering the ampage?

no, you can change volume by increase amplitudo input signal or voltage

try make input more voltage to your speker .

sorry if i wrong

[Octember13]

I'm pretty sure increasing the ampage would also increase the voltage, but I could be wrong on that.