DTMF infrared remote control circuit
The DTMF (Dual-Tone Multi-Frequency) infrared remote control circuit is designed to facilitate wireless control through the transmission of DTMF signals, which are commonly used in telephone dialing. The circuit incorporates a DTMF decoder that interprets the dual-tone signals emitted by a keypad or other input device. The LM567 phase-locked loop (PLL) audio decoder is a critical component that enhances the circuit's ability to accurately decode audio frequencies, enabling reliable signal processing.
In operation, the circuit generates a DTMF encoded signal, which consists of two simultaneous audio frequencies that correspond to the keypad buttons pressed. Each button on the keypad produces a unique combination of these frequencies, allowing for a wide range of control commands. When the signal reaches the DTMF decoder, it analyzes the frequency components and outputs a corresponding digital signal that represents the specific command.
However, it is essential to note that a single decoder can only process one frequency at a time. To create a complete control signal, the circuit must utilize two decoders working in tandem. By combining the outputs from both decoders, the system can generate a more complex control command that encompasses multiple actions or functions.
The infrared remote control signal produced by this circuit is transmitted via an infrared LED, which emits the encoded signal as light pulses. A compatible infrared receiver detects these light pulses and converts them back into electrical signals, which can then be processed by a microcontroller or another control system. This design allows for versatile applications, including remote operation of electronic devices, automation systems, and more.
Overall, the DTMF infrared remote control circuit represents an effective solution for wireless control applications, leveraging the reliability of DTMF signaling and the efficiency of infrared communication technology.The DTMF infrared remote control circuit. The DTMF encoded signal can be decoded by the special decoder and the PLL audio decoder LM567. But the DTMF encoded signal which is decoded by only one decoder, has only one frequency, one group of control signal is composed by two decoder`s output frequency. The infrared remote control signal which is produced by th.. 🔗 External reference
Related Circuits
A simple and inexpensive automatic night light circuit designed using the timer IC NE555, which extinguishes after a preset time. This time can also be adjusted. The automatic night light circuit utilizes the NE555 timer IC configured in monostable mode....
This device and all information contained on this website is for educational purposes only. This device must be used in conjunction with any and all local, provincial, and federal laws. It is the responsibility of the end user to...
The circuit illustrated in Figure 3-97 features two contacts and is designed specifically for a 2kW dual-speed motor. In this configuration, SB1 is utilized for low-speed operation, while SB2 serves as the high-speed run button. The circuit operates by allowing...
The oscillator circuits presented on this page are derived from expired or non-maintained U.S. Patents. All circuits are formatted for "Electronic Workbench 5.12" or "Multisim 7" circuit simulation software. A note regarding SPICE simulation of electronic oscillator circuits: all...
A highly effective 1-watt FM transmitter circuit that is easy to construct. The circuit consists of four transistors: one functions as a stable oscillator, followed by a buffer stage to maintain frequency stability during adjustments. Next is a resonance...
This project has been set aside for several years. It was initially intended for programming old 8051 microcontrollers, which have since become obsolete. The project was recently revisited due to the need for a programmer for the Atmel Xmega...