This tutorial explains a Tone Generator Doorbell Circuit using dual IC 555 timers, also the circuit is simple and works well when we press the button One IC works in astable mode and other in monostable mode and it is very important for making sound to run a 8Ω speaker. Also, the circuit needs 9V […]
Hobby Circuits
9V Battery Powered Transistor Intercom Circuit
Intercom system is device for talking at short distance; so a 9V Battery Powered Transistor Intercom Circuit uses 9V battery which is good for home or office talk. Also, it uses only transistors which is easy to understand and works well. Furthermore, the circuit has mic and small speaker as sound and a BC547 transistors […]
Transistor Based Battery Heater Circuit
Transistor Based Battery Heater Circuit uses 12V DC with good heat and very portable; also circuit is good for outdoor, no-electric place, small incubator and emergency heat. Furthermore, it uses astable multivibrator with transistors and this transistors switch power transistor and run heat coils and finally, LED show if circuit is working. Circuit Working: Parts […]
Ultrasonic Mosquito Repellent Circuit
Mosquitoes are small bugs which are very annoying, as they also spread bad sickness like malaria and dengue; so this Ultrasonic Mosquito Repellent Circuit idea is to use high sound especially ultrasonic to above 20 kHz to scare mosquitoes. Ultrasonic sound can disturb them and make them go away, hence, this simple circuit makes that […]
Simple Boost Converter LED Torch Circuit using IC MAX660
Simple Boost Converter LED Torch Circuit using IC MAX660 is small but useful light tool, as this project use MAX660 chip to make LED torch work well. MAX660 boost 3V battery to higher voltage and can light many LEDs, furthermore, it is good for battery devices needing more voltage and with no inductor needed. Also, […]
Simple 555 Timer Based Time Sense Tester Circuit
Simple 555 Timer Based Time Sense Tester Circuit is fun and easy to make, it uses IC 555 and make time delay, so press one switch and start timer. Then guess time presses second switch and it stop and then LED show result and it is good for learning how brain feel time. Also, circuit […]