Multi Channel Remote Control System

Here is a hobby circuit of a multi channel remote control system, by which you can control 8 different appliances. The main sections of this multi channel remote control circuit are the RF receiver and transmitter. By using this circuit we can control 8 devices, each of them independently by pressing the push buttons. When the button is pushed, corresponding relay is turned ON and is turned OFF on the next push. Here the relay load current is dependent on the relay used. A serial encoder IC HT12E and a serial decoder IC HT12D are used, where the encoder IC encodes the parallel data to serial and decoder IC decodes the serial data to parallel during the wireless transmission. You must need a regulated power supply of 5 volt for this circuit because ICs 7476 and 74138 requires 5v for its operation. The main advantage of this system is that it does not require a ‘line of sight’ as compared to IR remote control systems; also it gives longer distance control.

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Bidirectional motor control (driver) circuit for Robotics beginners

How can we rotate a DC motor in clockwise and anti clockwise directions? Or how can we rotate a motor in forward and reverse direction? These are the popular question asked by many of the robotic beginners. DC Motor (control) driver circuits are the essential circuit of robotics workshop. L293D IC is widely used for implementing DC motor control circuits. It is a dual H bridge motor driver IC, that is it can drive two DC motor simultaneously and is available in 16 pin DIP package. We have already posted H Bridge motor driver circuit with transistors. L293 driver IC has a current capacity of 600mA per channel and  a wide supply voltage range (4.5 to 36V DC). They are integrated with internal high speed clamp diodes for inductive spike protection. Other superior features of L293 are high noise immunity, internal ESD protection, thermal shutdown and separate input supply for each channel.

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H Bridge motor driver theory & practical circuit using transistors- animation/ simulation: Getting started with Robotics

What is H Bridge driver circuit? How to build an H Bridge circuit? H Bridge is a topic of great discussion in Robotics engineering and automation and H bridge motor (driver) controllers are the most common circuit for many robotics hobbyists. Further H Bridge driver circuits are the initial step of getting started with robotics (how to make robots? build a robot, etc). This Transistor H Bridge tutorial is devoted to the theory and practical construction of simple H bridges for controlling DC motors. An H-bridge is a type of driver circuit that you can use to spin a DC motor both clockwise and counterclockwise. H Bridge ICs are also available, L293 dual H Bridge IC is used in many robotic applications.

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Transistor act as a switch: DC Motor control (driver) circuit with animation

In one of the previous article we had already discussed about How transistor acts as switch? Here is another example of bipolar junction transistor BJT switching. In this case we will study a high voltage switching circuit i.e. how a transistor act as a switch for cutting flow of current when a high voltage flows. Today BJT switches are common in many electronic circuits and control systems. The main application of 'transistor act as a switch' is in the automation field.This example article explains how a transistor can control a DC motor. Animated working of transistor switch is also given for better understanding.

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