There are a lot of "YouTube circuits" that use color changing LEDs to trigger things as they cycle.

I want a circuit without LEDs to drive the buzzer with dual tone.

 

You need a buzzer that can generate a dual tone.
Do you have a buzzer?

You could drive a small speaker with a 555 astable oscillator that can be configured to generate more than one tone.

 

You need a buzzer that can generate a dual tone.
Do you have a buzzer?

You could drive a small speaker with a 555 astable oscillator that can be configured to generate more than one tone.

Yes, its a general 12v Buzzer

 

Does it buzz (or make its sound) when 12 volts is applied? If so then it's tone is internally controlled, you're not going to be able to change that.

 

I believe the TS is willing to abandon the circuit he provided and create a circuit with parts he can get to make a "two tone" buzzer. The ambiguity is what "two tone" means.

Does it mean an alternating tone like low, high; or does it mean two tones at the same time like a chord?

Also, which parts are available? It will require a speaker and the obvious thing is 555s.

 

If you can obtain a small speaker and a 555 timer, than we can show you how to build it.

Do you want it to continuously change between the two tones by itself at some slow rate, like once or twice per second?

 

The circuit shown with all the photos uses a transistor that is not needed.
The 330 ohm resistor is not needed and should replace the 100 ohms resistor for the current to be about 20mA.
It uses a piezo beeper that works from DC.

Maybe he wants the sound to be a European siren: bee, boo, bee, boo etc.

 

Thanks for all replies.
If there is a possibility to control the tone of the same buzzer by using an external circuit such as Astable Multivibrator, I would go for that.
Else, I would go for another circuit.

I'm using the circuit for an alarm.

 

If there is a possibility to control the tone of the same buzzer by using an external circuit

Not likely.
What is the buzzer you want to use.

 

Not likely.
What is the buzzer you want to use.

Any tone other than general beep tone.

 

@rafiec14 this thread seems to be going in circles. Which type of circuit do you want to go with and what "buzzer" do you have access to?

 

@rafiec14 this thread seems to be going in circles. Which type of circuit do you want to go with and what "buzzer" do you have access to?

I want to go with an alarm circuit. I have that circuit and I just want to change the general beep sound buzzer at the output to get other tone (or dual tone ). I think I'm clear now.

 

Thank you. It is getting clearer. What circuit is that?

 

Thank you. It is getting clearer. What circuit is that?

It is a water level indicator circuit in which I'm using a relay to drive the buzzer.

 

Good,
can you describe or publish the water alarm circuit?
You already said that it will be driven by a relay.

What type of "buzzer" do you have available and want to use?

What voltage is the power source?

How do you want to use the two tones? Warbling*, tone depends on type of alarm,...?
Earlier you wrote: "Generally, a buzzer gives a continous tone in any circuit. My requirement is to vary the continuous tone." That would be "warbling*".
*Example: To warble is to sing in an uneven, quavering voice.

Are there any constraints upon the design that have not been covered?

 

Using two astable circuits and the first one to modulates the second one, like:
556*1
555*2
CD4069*1
74HC14*1
Etc...

And adds a bjt or MOSFET to drive the Buzzer.

 

Using 555 stable curcuit for water level alarm then it could be google 555 organ circuit.

 

IF the circuit is equal to that one shown in post #7, it may be that the voltage applied to the sounder is varied by the changing current draw of the "RGB" LED device, which has been mentioned here once, at least. In that circuit the device incorrectly called a buzzer might have some variations in amplitude, because what is shown must be a device similar to the "Sonalert", the original DC powered sounder.
So not only has this thread wandered in a circle, it has reached the center and fallen down into the rat hole.
So the short answer is that "NO", you can not get significantly different sounds from a device whose frequency is set by the mechanical resonance of the sounder disk, and whose components are all inside a sealed package.

The very best that could be done is to rapidly pulse the sounder on and off, possibly very rapidly.

With a different sounder that is not sharply resonant and does not include internal circuitry, there are many possibilities, several already shown.

 

Would the single tone buzzer be acceptable if it gave an interrupted tone - beep beep beep...

 

39 posts in, about half of which ask what tyoe of “buzzer” the TS has and what he means by “dual tone”, and no comprehensible answer yet on either question.

Bob