Multivibrator switch

Hello,

it’s been great fun studying all the projects in this edukit, but I want to take things one step further with the buzzer. I want to make a circuit which switches between feeding the buzzer with a high current and feeding it with a low current. Basically, I want it to alternate between buzzing loudly and buzzing less loudly. Is this possible with the components included in this kit, or do I have to get some kind of IC?

I’ve tried hooking the buzzer into the astable multivibrator, but from the result I guess that wasn’t a very clever idea (I think I bypassed the transistors by doing it and the buzzer made no sound if I recall correctly).

I still have a long way to go before I fully understand the basics about how all the components work and how they should be used together. Sorry if this is the wrong place for this kind of question.

A resistor with a low value in series with the buzzer can make it sound less loud.
Please experiment with the value, you cannot damage the unit.

Thank you for your answer, but I should have mentioned that I’ve already tried that. So far I’ve built this:

Btn1 and btn2 are push-buttons, I want to eliminate them from the circuit and replace them with something that will automatically switch between the 1K resistor and the 10K in order; similarly to how the astable multivibrator switches between two leds. Is it even possible without an IC?

You could experiment with something like this.
For component values, please check multivibrator circuit of EDU01.
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http://www.velleman.eu/images/tmp/twotonebuzzer.jpg

Thank you very much! That works great and it’s exactly what I was looking for :smiley: