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Topic: Getting a nice sound from piezo (Read 3423 times) previous topic - next topic

Grumpy_Mike

#15
Jun 29, 2016, 09:03 pm Last Edit: Jun 29, 2016, 09:03 pm by Grumpy_Mike
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Not sure about that,
Then you can't begin to design a filter for it. Sorry it looks like you are going to have to give up. Their are only a limited number of options. Maybe some one else can think of one.

pjrc

Do you know of a very simple circuit that would work?  I'm trying to keep it as simple as possible.
The problem is human brains are far too smart.  They perceive very simple sounds as annoying.

Your desire for a "nice" sound is fundamentally in conflict with your design for a simple circuit.

Feddar

Hmmm

I got a buzzer with a driver in it, and it has a decent sound.  Maybe I should take it apart and see what driver it is using.

I've tried several permutations with the above 555 circuit, at 12V, but I cannot get the output to be greater than 8V. Any idea why that would be?

pjrc

Maybe I should take it apart and see what driver it is using.
You probably should.

And if you learn anything valuable, maybe you should take some time to share the info to help others?

tmd3

I've tried several permutations with the above 555 circuit, at 12V, but I cannot get the output to be greater than 8V. Any idea why that would be?
How are you measuring the output voltage?

Feddar

How are you measuring the output voltage?
I am using a cheapish multimeter.

DVDdoug

#21
Jul 01, 2016, 04:47 pm Last Edit: Jul 01, 2016, 04:47 pm by DVDdoug
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I am using a cheapish multimeter.
A multimeter won't measure accurately...  You've got a signal that's changing rapidly between (approximately) 12V and ground (zero).     If it's a square wave, the average (and RMS) voltage is about 6V.

There are some higher-end meters that can measure true-RMS (usually when set to read AC voltage).

A cheap meter will accurately read DC or an AC sine wave (within its accuracy capabilities) but with a square wave (or a pulse) the readings are unreliable.   On the DC scale, you'll probably get the average or something close to an average.

If you had an oscilloscope you'd see the waveform shape and you could read the peak voltage.    (I have 'scopes at work, but like most hobbyists I don't have one at home....  I'm not implying that you need one.)

tmd3

... I cannot get the output to be greater than 8V. Any idea why that would be?
I am using a cheapish multimeter.
It seems clear that you were expecting some other reading on the meter.  What reading did you expect?


Feddar

If it's a square wave, the average (and RMS) voltage is about 6V.
Thanks, that helps.

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If you had an oscilloscope you'd see the waveform shape and you could read the peak voltage.
I might get a DIY one...

Feddar


Grumpy_Mike

How about usic a CAPACITANCE CERAMIC RESONATOR to run the buzzer?
How good is your hearing? The lowest frequency one is in the order of 2MHz.
Not sure what you mean by "run" the buzzer.

Feddar


Amal_ns

guyz,any one have the code for radar sound

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