beep or chirp sound

[scottnj]

What device is used to make a nice beep when you push a button?

 

[Alun]

A piezo buzzer?

 

[scottnj]

A piezo buzzer will make a beep? Then why do they call it a buzzer? ;D
How do you use these? Can you set the tone?

 

[hamoodyjamal]

You can build one your self. Just use a 555 timer set to say 500Hz (the frequency should be between 20Hz to 20KHz - human ear range) to drive a small speaker. Basic really.

Yet again, you can always use a buzzer, or a relay (thats right, sounds wierd but true i can tell you if your interested)

Later ;D

 

[scottnj]

I have a PIC in my project, I think I can turn a pin on/off in that frequency range. Is this how the buzzers work? If so, I adjust the tone in my firmware?

Can you adjust volume?

I would like to minimize components and keep to a small space. The PIC can only source/sink ~25mA.

 

[Alun]

A piezo buzzer will make a beep? Then why do they call it a buzzer? ;D

I don't know, I suppose as far as electronics goes any device that you connect up and it produces a tone is a buzzer, a car horn works on the same principle as an electromechanical dorbell buzzer, but a piezo buzzer is different it uses piezo transducer conected to an oscillator.

How do you use these?

Just connect the + to the output of your circuit and the 0V to 0V - simple as that.

Can you set the tone?

No they are fixed tone devices,  2KHz is the normal frequency and it sounds like a beep probably the same pitch as most electronic devices such as alarm clocks and smoke detectors, do you really need to change the frequency?

I have a PIC in my project, I think I can turn a pin on/off in that frequency range. Is this how the buzzers work? If so, I adjust the tone in my firmware?

Can you adjust volume?

I would like to minimize components and keep to a small space. The PIC can only source/sink ~25mA.

The current consumption is also very low, most units consume less than an LED so in my opinion a piezo buzzer is the best device for your application unless you want to change the frequency or anything fancy.

 

[scottnj]

Thanks Alun,
That sounds exactly like what I need. Easier the better. I don't want it to be adjustable, I just got confused from trying to read some other web page.

 

[audioguru2]

A piezo transducer is a piezo buzzer without its built-in oscillator. If you drive it with musical frequencies it will play a high-pitched song. You can adjust its volume in steps if you feed it with resistors from multiple outputs from the PIC. You can make it much louder if you drive it with push-pull outputs. ;D

 

[scottnj]

Looking in the mouser catalog, there are a lot to choose from. It looks like I may have to buy a few different ones to see what frequency sounds best.

Are there any computer programs that let you enter a frequency and play it through the speakers?

How loud are these things? They seem to range from 70-105db, but I don't really know how loud that is. I want to be able to easily hear it, but not be anoying.

Any recomendations for a starting point so I don't spend too much $.

 

[scottnj]

I found some software to generate signals. Its called speclab and does a lot of other things to.
http://www.qsl.net/dl4yhf/spectra1.html
I liked the 2kHz-3kHz range. How different will these sound compared to a pure sine wave? I guess it doesn't really matter, since these seem like my best option.

Now I just need to figure out the db.