Ticking Sound Generation Using BC547 and BC557
Since the invention of the transistor electronics has evolved fast, it started with transistors being huge in the form of point contacts, vacuum tubes and today we have IC where Each IC has an equivalent of billions of transistors.
Though most of the world has switched over to micro controllers and other IC related projects it is still fun to do projects using transistors.
In this tutorial I'm going to show you one such project using the BC547 and BC557 transistor it is a circuit that generates a sound like a ticking clock that would make a good movie prop to emulate a loud clock ticking noise or to make a fake bomb prop.
Step 1: Bill of Materials
For this project you will need
- BC547 & BC557 Transistor
- 10uf Capacitor
- 2.2 uf Capacitor
- 10K resistor
- 1K resistor
- 100K Pot
Step 2: Circuit Sketch
The circuit for this project is simple you could refer to the images above while assembling it, this project can be easily assembled on a Breadboard. This circuit works by quickly, charging and discharging of the 2.2uf Capacitor and the capacitor causes both the transistors to turn on an off alternatively creating the ticking noise.
Step 3: Freqency of the Ticking
The frequency of the ticking of the clock can be varied by changing the value of the 100k pot, turning the pot using a screwdriver in either direction should either increase the frequency of the tick or decrease the frequency of the tick.
Step 4: Going Further
Now that you have the circuit ready you can make a more permanent model by soldering it on a PCB, if you don't know how to solder there are a ton of YouTube videos on how to do that that you can lean soldering from.
If you like a series of transistor circuits let me know and I would be happy to post more instructables on it.