Over years we have developed a number of FM transmitter circuits with various aspects. Today I thought of listing all of them here as a single web page, so anyone can easily navigate through all the radio transmitter circuits and its schematic diagrams. For first time readers- What is an FM transmitter An FM transmitter […]
PLL FM demodulator. 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 range, 4.5 to 20V operating voltage range, 2mV to 3Vrms dynamic range, high
AN7415 FM Stereo Demodulator. 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 applications. AN7415 has low current consumption (2.6mA), low
LM1800 is an integrated FM stereo demodulator IC which has a number of good features integrated on it which makes it possible to design a high quality FM stereo demodulator system with excellent sound quality. The LM 1800 uses phase locked loop technology to regenerate the 38kHz sub carrier from the composite signal. The features
AM radio circuit using TDA1572. The circuit shown below is of a high performance AM receiver designed based on the TDA1572 IC from Philips. The TDA1572 is an integrated AM receiver circuit that has all essential circuitries like RF amplifier, mixer, IF amplifier, AGC circuit, signal strength indicator driver, audio pre amplifier, controlled oscillator etc
CXA1019 FM receiver circuit 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, quadrature detection circuit, tuning LED driver electronic volume control, detector etc. FM section
Stereo decoder circuit. In FM stereo transmission left and right channels are algebraically encoded into sum (left + right) and difference (left-right) signals. This is done in order to make the mono FM receivers compatible with the stereo transmission. The mono receiver will reproduce the summed left and right channel and the listener will hear
MK484 AM receiver circuit Description. A simple AM receiver circuit based on the MK484 AM receiver IC from Rapid Electronics Ltd is shown here. MK4844 is a monolithic integrated circuit that has all the necessary sections of a AM receiver like RF amplifier, detector, AGC etc. The IC is available in TO92 package and requires
Description. This is the circuit diagram of the simplest single chip AM radio. The circuit is designed around the IC ZN414Z which is a ten transistor tuned radio frequency receiver .The IC has only three leads and is available in the TO92 package. All necessary circuits required for an AM receiver (RF amplifier, detector and
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. Powerful VHF oscillations from the circuit will interfere with the FM signals to nullify it.
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 modulator as well as oscillator. Capacitor C2 and inductor L1 forms the necessary tank circuit for
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. Transistor T1 is wired as a preamplifier whose output is further amplified by the IC
Description. Here is the circuit diagram of an FM transmitter using the IC UPC1651. UPC1651 is a wide band UHF Silicon MMIC amplifier. The IC has a broad frequency response to 1200MHz and power gain up to 19dB.The IC can be operated from 5V DC. The audio signals picked by the microphone are fed to
Description. This is a very simple AM radio circuit using only two transistors. The coil L1 and variable capacitor C1 forms the tank circuit. Transistor Q1 does the job of demodulation. The demodulated signal will be available at the base of Q1.This audio signal is coupled to the base of Q2 for further amplification. The
Description. Here is the circuit diagram of a simple radio that uses one transistor and few other passive components.The C6 and L1 forms a tank circuit which picks up the signal from your desired radio station.Diode D1, capacitor C2 and resistor R1 does the detection of the picked signal.The detected signal is coupled to the
Description. This is a simple and low cost wide band VHF field strength meter. The field strength is measured by converting the radio signal to DC and measuring it. The RF signal will be picked up by the coil and rectified by the diode D1.Even a very small DC voltage is sufficient to alter the
Description. Here is a low cost AM receiver circuit that can be tuned from around 550 to 1100 KHz. Three transistors are used in this project. The transistors Q1 and Q2 are wired as a compound transistor pair in which Q1 is an emitter follower and Q2 is a common emitter amplifier. The emitter follower
 Description. Low power ( 3 to 30 MHz) transmitters constructed by hams are generally called QRP’s. For such transmitters a well tuned antenna is a must.If the impedance is not properly matched there will be a little or no output.But if properly matched there will be great results.A circuit for matching the antenna properly with
Description. Here is a handy field strength meter that can be used to check the strength of AM radio signals.The circuit is a very useful for those who assemble radio transmitters(especially in the tuning of the final stage for maximum range). The circuit is essentially some sort of a AM receiver it self. The capacitor
Description. Here is the circuit diagram of a versatile FM transmitter that doesn’t have a coil. The circuit is simple and easy to assemble. The gate N1 acts as a buffer for strengthening the signals from the condenser microphone. The inverter N2 with its associated components forms a radio frequency oscillator in the FM region.The
Description. The circuit presented her will transmit a audio tone in the FMÂ 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 this. The transmitter has a range of 100m @ 9V supply, with a matching
Description. When there is a fire breakout in the room the temperature increases. This ultra compact and low cost fire alarm senses fire breakout based on this fact. Transistor BC177 (Q1) is used as the fire sensor here. When the temperature increases the leakage current of this transistor also increases. The circuit is designed so
Description. Here’s a low cost radio circuit that can be used to listen to the radio conversations between aircrafts. The radio circuit based on transistor 2N918 and diode 1N82 receives in the 220Mhz to 400Mhz range. Capacitor C1 and inductor L1 forms the tank circuit for tuning. Diode D1 performs the detection. Transistor T1 performs
Simple AM Transmitter Transmitters are devices that are capable of transmitting audio as radio waves from an audio device. There are two types of transmitters; FM & AM. We have many posts on FM transmitters, so we decided to make one on AM transmitter. AM transmitters create radio waves using Amplitude Modulation (that’s why AM).
Single chip FM transmitter An FM transmitter is a device that can transmit audio from an audio device as a radio signal. Doing so allows the audio to be picked up and played by an FM radio in the transmitter’s range. The FM (frequency modulation) device allows the waves to move in predefined frequencies so
