Atmel AVR ISP Dongle
Atmel’s AVR microcontroller chips are in-system programmable (ISP), i.e. these can be programmed directly in the target circuit. A special programmer software is used...
Smart Switch
To switch on the mains voltage, either a mechanical switch or a relay offers a simple solution. However, the relay and its associated components...
Transistor Tester
With this transistor tester, you can test both npn and pnp transistors using this circuit. The circuit indicates whether the transistor is good, open...
Automatic Dual Output Display
This circuit lights up ten bulbs sequentially, first in a direction from first bulb to last bulb and then in a reverse direction.
Reaction Time Game
This reaction time game tests the time taken by two players to react, and declare the fastest one as a winner. To do this...
Simple USB Interface Signal Monitor
Presented here is a simple, low-cost USB interface signal monitoring circuit. It can be used to monitor signal activity for most of the USB...
Getting Started With NodeMCU Development Board For IoT
Since Internet of Things (IoT) projects are now quite popular, I recently bought a NodeMCU board to try IoT application development. The NodeMCU development...
30W Audio Amplifier Using NE5534 and Darlington Transistors
There are many different audio power amplifier ICs to choose from, but designing an audio power amplifier using an operational amplifier (op-amp) and bipolar...
Fan Speed Increasing Regulator Using PIC16F73
Voltage dips in mains supply make fans run very slow, leaving you sweaty through hot summers, especially if you don’t own an air-conditioner (AC)....
Design and Analysis of A Single Stage Transistor Amplifier Using C++
Single stage transistor amplifierDesign GuidelinesSoftware ProgramDownload source code: click here
Designing a single-stage transistor amplifier requires numerous formulas to calculate various parameters, such as the...
Electronics Projects: Controlling a Stepper Motor Using a Rotary Encoder
Presented here is a project for controlling stepper motor using rotary encoder. It consists of a Raspberry Pi (Raspi) board, 5-pin rotary encoder, 5V...
Microcontroller Projects: Home Automation System
In this era of digital revolution, we are surrounded by smart devices that are capable of making decisions on their own without much human...
Microcontroller-Based Tachometer
A tachometer is nothing but a simple electronic digital transducer. Normally, it is used for measuring the speed of a rotating shaft. The number...
Moving Message Display On LCD
A moving message display is ideal to get your message (advertisements, greetings, etc) across in an eye-catching way. You can make an LCD show...
Microcontroller Based Clock Using DS1307
Digital wall clocks, table clocks and desk clocks with pointer or LCD display are readily available in the market. Here we present a microcontroller...
Phase Angle Control Of SCR Using AT89C51
Silicon-controlled rectifiers (SCR) are solidstate semiconductor devices that are usually used in power switching circuits. SCR controls the output signal by switching it ‘on’...
Simple Soldering Iron Temperature Regulator
Soldering irons are available in different wattage and usually run at 230V AC mains. However, these have no temperature control. Low-voltage soldering irons (e.g.,...
Tachometer
Non-Contact Type Digital Tachometer
Low-Cost Tachometer
Simple Tachometer
DIY Tachometer built with a Microcontroller.
The article was originally published in December 2010...