TX-2B / RX / 2B 5 channel radio remote control. This article is about a simple 5 channel radio remote control circuit based on ICs TX-2B and RX-2B from Silan Semiconductors. TX-2B / RX-2B is a remote encoder decoder pair that can be used for rem… Read more »
Description. Here is a simple circuit in which an LED will continue flashing as long as the voltage of the battery to be monitored is above the set level.The transistors Q1 and Q2 are wired as a complementary astable multivibrator.The circuit can… Read more »
Description. A very simple battery charger circuit having reverse polarity indication is shown here.The circuit is based on IC L200 . L200 is a five pin variable voltage voltage regulator IC.The charging circuit can be fed by the DC voltage from a… Read more »
Description. The circuit given here is designed by Mr.Seetharaman V.S (seethasub@hotmail.com) from Chennai. Seetharaman’s comments about the circuit: This circuit is a modification of High & Low voltage cut-off with delay& alarm circuit appeared … Read more »
LDO regulator means low dropout regulator. An LDO voltage regulator is just a DC linear voltage regulator which can be operated with a very small input-output voltage differential. This input output voltage differential is called dropout voltage… Read more »
Regulated DC Power Supply using transistors. A low ripple regulated DC power supply designed based on transistors is shown here. Such transistor voltage regulators are suitable for application where high output current is required. Conventional in… Read more »
12V/120mA switch mode power supply circuit. Transformer less switch mode power supplies have become very popular these days. The circuit shown below is of a 12V/120mA output, 85 to 230V AC input transformerless switch mode power supply using LNK304… Read more »
MSK5012 is a highly reliable adjustable voltage regulator.Whose output can be programmed using two resistors. The regulator has a very low dropout voltage(0.45v @10A )due to the usage of MOSFET with very low Rds (ON) as the internal series pass … Read more »
Description. Here is the circuit diagram of a battery eliminator circuit that can be used as a replacement for 9V PP3 batteries. The circuit given here can be used to power any device that operates from a 9V battery. The transformer T1 steps down… Read more »
Description. The circuit diagram shown here is of a automatic changeover switch using IC LTC4412 from Linear Technologies. This circuit can be used for the automatic switchover of a load between a battery and a wall adapter.LTC4412 controls an ex… Read more »
LM3914. The heart of this circuit is the LM3914 from national semiconductors. The LM3914 can sense voltage levels and can drive a display of 10 LEDs in dot mode or bar mode. The bar mode and dot mode can be externally set and more than one ICs ca… Read more »
Description. Here is a simple charger circuit for charging SMF(sealed maintenance free ) batteries.The charger circuit being curernt and voltage regulated,can be safely used to charge SMF batteries of 1.2 AH rating.This circuit was actually design… Read more »
Description. Here is the circuit diagram of an effective and super fast Ni-Cd battery charger circuit.The circuit is based on the IC MAX 712. The circuit is designed to fast charge a Ni-Cd battery at 3oomA. After the fast charging is completed … Read more »
Description . Here is the circuit diagram of a simple and straight forward 12 V battery charger circuit with diagram. This circuit can be used to charge all type of 12V rechargeable batteries including car batteries. The circuit is nothing but a 1… Read more »
Description Here is a lead acid battery charger circuit using IC LM 317.The IC here provides the correct charging voltage for the battery.A battery must be charged with 1/10 its Ah value.This charging circuit is designed based on this fact.The ch… Read more »
Description This is a very useful circuit which when installed on your car gives the voltage of you car battery in a LED dot display form.The circuit is based on four comparators made of quad op amp LM324.The inverting inputs of IC are kept at at… Read more »
Description Here is a easy to build low battery level indicator circuit that produces a visible indication by flashing a LED when the battery voltage drops below a predetermined voltage.The circuit is based on Panasonic’s IC MN13811G and a eff… Read more »
Description. Many electronic circuits related to fan speed controlling have been published here and this one is just another approach. The circuit diagram shown here is of 12V DC fan speed controller using the IC LM2941CT which is a low drop out … Read more »
Description. Here is the circuit diagram of a simple stepper motor controller using only elementary parts. The driver circuit uses, four transistor (SL100) to drive the motor windings, two NOT gates and one XOR gate to decode the two bit control l… Read more »
Description. Here is a simple circuit based on two transistors that can be used to control the speed of a 12 V DC fan depending on the temperature.A thermistor (R1) is used to sense the temperature. When the temperature increases the base current … Read more »
Here is a remote operated spy robot circuit which can be controlled by using a wireless remote controller. It can capture audio and video information’s from the surroundings and can be sent to a remote station through RF signals. The maximum rang… Read more »
Description. The circuit given here is of a simple H bridge motor driver circuit using easily available components. H Bridge is a very effective method for driving motors and it finds a lot of applications in many electronic projects especially i… Read more »
Description : A bidirectional H bridge DC motor control circuit is shown here. The circuit is based on the IC L298 from ST Microelectronics. L298 is a dual full bridge driver that has a wide operating voltage range and can handle load currents up… Read more »
Description. A simple DC motor controller circuit using NE555 is shown here. Many DC motor speed control circuits have been published here but this is the first one using NE555 timer IC. In addition to controlling the motors speed its direction of… Read more »
Description. Here is the circuit diagram of a simple and low cost AM radio. The working of this radio circuit is straight forward. Inductor L1 and capacitor C1 forms the necessary tank circuit. Diode D1 performs the job of de-modulation. Transist… Read more »
Description. With this compact FM adaptor circuit plugged into the audio out of your cassete player or i Pod out put,you can listen your favorite music on your car stereo.This circuit is very useful if your car stereo doesnot have an auxillary in … Read more »
AN7415 is a monolithic integrated circuit that can be used in FM stereo demodulation applications. The operating voltage range is 1.6 to 7Vdc. Two AA dry cells are enough for powering this IC and it makes the AN7415 suitable for handheld FM radio… Read more »
A simple PLL FM demodulator circuit using IC XR2212 is shown here. XR2212 is a highly stable, monolithic PLL (phase locked loop) IC specifically designed for communication and control system applications. The IC has 0.01 Hz to 300KHz frequency r… Read more »
Description. The circuit presented her will transmit a audio tone in the FM band. The circuit can be used as a tracking signal transmitter or a remote control transmitter. The circuit uses only easily available components and any one can build … Read more »
Description Here’s a single chip FM transmitter circuit using Maxim semiconductors IC MAX2606. The MAX2606 is a compact, high-performance intermediate frequency VCO specially designed for wireless communication circuits. They have monolithic co… Read more »
Description. This is a simple, but very useful circuit that can be used to transmit telephone conversations. When the telephone receiver is on hook the voltage across the lines will be about 48 volts. The preset R7 is so adjusted to obtain a 24.7 … Read more »
A high quality FM receiver circuit based on CXA1019 IC is shown here. CXA1019 is a bipolar silicon monolithic FM/AM radio receiver IC from Sony. Built in circuitries inside the CXA1019 include RF amplifier, mixer, oscillator, IF amplifier, quadr… Read more »
Description. Here is the circuit diagram of the simplest FM transmitter using a transistor. Great performance or range is not guaranteed here, because this is an elementary design. General purpose radio frequency transistor BF 494 (Q1) is used h… Read more »
Description. Circuit shown here can be used to jam FM radios in its vicinity. The circuit is nothing but a classic single transistor oscillator operating in the VHF region. Working principle of the circuit is very simple and straight forward. Pow… Read more »
Description. This could be the simplest FM transmitter circuit you can find on the internet. Only using a single transistor and few passive components, this transmitter can deliver signals up to 50 meters. The transistor Q1 serves as the modulato… Read more »