6 LED voltage indicator circuits
This is four circuits of LED voltage indicator are simple and easy to builds for check voltage battery and others, use as zener,transistor,LM339 and more Read more
Meters & Detectors
6 ranges AC millivoltmeter circuit
Sometimes, we need to measure a too tiny AC voltage level. And high frequency too. Ohh… We cannot use general multimeter. I recommend you try watching the AC millivoltmeter circuit. It includes the 6 ranges. Lowest is 15mV only. Also, it uses an analog meter form. So, you can watch easily a slow changing of … Read more
Simple Refrigerator/fridge Door Alarm circuit
This is a Simple Refrigerator Door Alarm circuit, it will detect light of lamp in the fridge and alert with buzzer.Small size, easy to make and cheapest. […] Read more
Diy digital voltmeter panel meter 0-50V
This is Diy digital voltmeter panel meter 0-50V is 0-50V scale. Display with LED 7 segment. In cost 3$ dollar only, builds simple regulator dc power supply Read more
Simple SCR tester circuit diagram
Simple SCR tester circuit diagram is very useful. We can know location pin on gate lead, anode lead and cathode lead. can also test diode, LED and Triac Read more