Light-Controlled Bird
Here's an electronic bird that will sing for you from morning till night ... but his singing will change as it gets near sundown.
After you finish the wiring connections, turn the power ON. You'll hear a sound like a chirping bird from the Speaker.
Now trying varying the amount of light that fails on the CdS Cell by covering it with your hand or shining a flashlight on it. You'll notice the chirping becomes faster in bright light.
You can also alter the chirping rate with the 50K Control. There's some parts in this Project you might be tempted to change, such as the 100 uF capacitor or the 1K resistor. There are others, of course, but we want you to find them for yourself!