Basic SPST (Single-Pole,Single-throw) switch
Mechanical switches permit or interrupt the flow of current. They are also used to direct current to various points. The basic knife switch is the simplest switch. OPEN = OFF , Closed = ON. This is called an SPST (Single-Pole,Single-throw) switch.
Easily draw circuit by easyEDA
My son draw circuits by a pencil, which is not beautiful at all as Figure 1. We found a way to draw a good and perfect EasyEDA.com, we can do circuit simulation, PCB design, Electronic circuit design online for free. It works well on Mac, Linux, Windows and Android: All …
How to fix unclear the 7 segment led display
I’ve bought a cheap digital frequency counter kits. It works great, can measure frequency up to 1GHZ in 19$ only. It use 8 the LED 7 segment display. But it’s a little brighter so cannot clearly read the value. Figure 1 low brightness LEDs My son fix easily this problems …
How to calibrate touch screen GARMIN GPS
I like taking the kids to tour upcountry. We purchased a GARMIN GPS to reduce stray. I like it because it can Map update any lifetime and cheap. But yesterday have a problem white screen with a message that touch dot. I try to calibrate touch screen. I started to …
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 …
Pulse Generator Oscillator 32.768KHz by watch crystal
My Friend need to like a Pulse Generator Oscillator circuit that stable frequency at 32.768KHz with watch crystal,for digital CMOS binary counter, so he tell to me even low prices. I think may be used the watch crystal and IC4069 or IC4049 inverter CMOS IC. They are very cheap and …