In this post I have explained how electret microphone devices work, through appropriate diagrams and formulas. What’s a Microphone A microphone is a device designed for transforming weak sound vibrations into tiny electrical pulses, which can be then amplified through a power amplifier over a loudspeaker for achieving a louder reproduction of the sound. The […]
Newly Updated Circuit Projects:
LM317 with Outboard Current Boost Circuit
The popular LM317 voltage regulator IC is designed to deliver not more than 1.5 amps, however by adding an outboard current boost transistor to the circuit it becomes possible to upgrade the regulator circuit to handle much higher currents, and upto any desired levels. You might have already come across the 78XX fixed voltage regulator […]
Bicycle Speedometer Circuit
In this article I have explained how to build a simple bicycle speedometer circuit which can be used to measure the speed of the bicycle. Video Demonstration What is a Bicycle Speedometer, How it Works Bicycle speedometer is a device which checks the rotation per minute of the bicycle wheel and displays the results over […]
Solar Battery Charger using LM339 Comparator
This small LM339 based solar battery charger setup is designed to optimize the charging of your battery using any solar panel while protecting it from accidental overloads. Considering the extended battery life it allows you to achieve, it is an investment that quickly pays for itself. Circuit Description Our setup is nothing more than a […]
PWM Solar Battery Charger Circuit
This simple, enhanced, 5V zero drop PWM solar battery charger circuit can be used in conjunction with any solar panel for charging cellphones or cell phone batteries in multiple numbers quickly, basically the circuit is capable of charging any battery whether Li-ion or Lead acid which may be within the 5V range. Using TL494 for […]
Sound Activated LED Lamp Circuit
A highly sensitive sound activated LED lamp circuit can be built using just a few transistors and resistors. The circuit is actually a high gain MIC amplifier circuit which amplifies the external sound hitting the MIC. The amplified signal is then used to momentarily illuminate a bunch of LEDs. What does the Circuit do? Basically, […]