Simple big robot toothbrush
Today, My son make a toy for younger sister. It is a Simple big robot toothbrush. The principle is very simple, It vibrates with movement, without direction and control. He took it to play with the cat great fun. Figure 1 the Simple big robot toothbrush He uses all old …
Simplest Automatic Solar Light
This is simplest automatic solar led light circuit that my son try to make it for basic small solar charger. This circuit is a simplest circuit. He trial it to learn about solar LED light, and makes it all by himself. He needs one LED light that brightest at night. …
Simple High power LED flashlight
This is simple hight power LED flashlight,we use 24 LEDs super bright for display and 3 AA batteries and resistor for limit current so cheaper. My son buy this LED flashlight but is low light. Thus, he want to builds the new high power LED flashlight with himself. How does …
Simple solar plant watering alarm
This is a simple Solar plant watering alarm circuit. It will sound alarms when the soil is dry. The trees have died. It the solar sell is 6V DC power supply. Thus saving convenience and does not require batteries.No noise at night. How the circuit works As circuit diagram in …
Fast blinking LED bike light circuit
This is a fast blinking LED bike light circuit For safety when the bike at night. We use two-NPN-PNP transistor oscillator circuit and RC circuit only show on 4 LEDs use low current. We take the four LEDs to parallel because each LED use voltage about 3 – 4.5V We …