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SIMPLE RADIO FREQUENCY REMOTE SWITCHING CIRCUIT RF TRANSMITTER SECTION Today we are going to discuss about the simple RF (Radio Frequency) Transmitter and Receiver circuit. RF(Radio Frequency) is a High Frequency signal commonly used for communication applications, due to its high frequency we can transmit signal to a sufficient distance (about 300 Foots) without attenuation. Here, the simple RF switching circuit is used to turn ON and turn OFF an LED (For Demonstration) you can replace the LED with a switching RELAY and control any appliances. Read More.....

Now a day, everyone wants to control their appliance wirelessly (i.e. remote control). Here is a simple tested and inexpensive remote control switch utilizing reading available components.   Circuit Description of infrared (IR) remote control switch As in all wireless systems Infrared (IR) remote control switch also comprise two major section i.e. transmitter and receiver section. Transmitter Section: – The logic of this section is simple and is build around most versatile IC NE555 (IC 1 ), configured as astable multivibrator to produce frequency about 38 KHz. This is so, because IR module receiver used here works in range of 38 KHz frequency. Timing component of infrared remote control switch is resistor R 1 and R 2 and capacitor C 2 , determine the range of oscillating. Where, formula of generated frequency (F) from transmitter section IR remote is given by F = 1.443 / (R 1 + 2R 2 ) C2 The output frequency from pin 3 of IC 1 is fed to base of transistor T 1 through resistor ...

This ultra-simple remote control extender is ideal for use with a hidden video recorder. The recorder is a Panasonic NV-SD200 and is used as part of a camera surveillance system. A PICAXE-08-based circuit is used to detect events and control the recorder. It also flashes a LED near the monitor to indicate the number of events since last viewing. Strangely, the NV-SD200 model refused to work with a number of commercial infrared remote control extenders, hence the need for this design. As a bonus, it uses less power than a traditional extender (no plugpacks) and the remote can still be used in the normal manner. As shown, an additional 5mm infrared LED is mounted directly in front of the equipment to be controlled. This is cabled back to a convenient location near the monitor and terminated in a 3.5mm plug. To modify the remote control unit, break the circuit to the anode of the existing infrared LED and wire in a 3.5mm headphone socket. In most cases, the LED will be accessible ...

Description  This is a simple type remote control by using RF communication without microcontroller. In this project a remote has been designed for various home appliances like television, fan, lights, etc. It gives lot of comfort to the user since we can operate it by staying at one place. We can control any of the appliances by using this remote within the range of 400 foots. In this project consist of two sections, transmitter (remote) and receiver section. Whenever we are pressing any key in the remote it generates the corresponding RF signals, and these signals are received by the receiver unit. ASK transmitter and receiver is used as transmitter and receiver. HT12E, HT12D encoders and decoders are used in this electronic circuit. The block digram of the whole circuit is given below.  Appliance Control Block Diagram Remote Section In remote section consist of an encoder (HT 12E) and a ASK transmitter. The encoder generates 8 bit address and 4bit data. We can set the addre...

While I was home this winter, I saw that the remote for our TV tuner was damaged physically, causing the buttons to not function responsively. Some of them just didn't work. I saw this as an opportunity for a fun couple days' project to build a new remote controller for the tuner. The TV tuner was manufactured by a brand name RealView and, as expected, I couldn't find much detail about it. Thus, I had to reverse engineer the remote. From my previous experience in working with IR remotes, I had a hunch that the IR was most likely modulated at ~38kHz or ~56kHz. For those of you who don't know how this works, I highly recommend going through this website: http://www.sbprojects.com/knowledge/ir/ Thus, I connected a 38kHz IR receiver I had at home (TSOP1738) to an oscilloscope in order to figure out what IR protocol is used by the remote. Upon pressing the 4 key on the remote, I saw the following waveform: Fig. 1: Oscilloscope waveform capture of the received IR signal Note...

Description: An Infra Red wired Repeater circuit to control appliances from a remote location. IR Remote Control Extender Circuit Diagram Parts List: R1: 1k Resistor (1) R2: 3.3k Resistor (1) R3: 10k Resistor (1) R4: 15k Resistor (1) R5: 2k2 Resistor (1) R6: 470R Resistor (1) R7: 47R Resistor (1) 0.5 Watt PR1: 4.7k Preset (1) C1,C3: 47u Elect(2) C2: 1n Polyester 5% or better (1) C4: 100u Elect(1) Z1: 5V1 Zener (1) Q1: BC549C or BC109C or 2N2222 (1) Q2: BC337 or BC549 or ZTX450 (1) IC1 : TSOP1738 IC2: 555 or 7555 (1) LED1 5mm RED (1) LED2,3 IR diode TIL38 or similar (2) Alternatives to IC1 : Everlight IR receiver module ELIRM 8621 Harrison electronics IR1 Vishay TSOP 1838 Radio Shack 276-0137 Sony SBX 1620-12 Sharp GP1U271R Notes: The signal emitted by an IR remote control contains two parts, the control pulses and a modulated carrier wave. The control pulses are used to modulate the carrier, a popular modulation frequency being 36 and 42KHz. The signal is radiated by an IR diode, ty...

This circuit confuses the infra-red receiver in a TV. It produces a constant signal that interferes with the signal from a remote control and prevents the TV detecting a channel-change or any other command. This allows you to watch your own program without anyone changing the channel !!    The circuit is adjusted to produce a 38kHz signal. The IR diode is called an Infra-red transmitting Diode or IR emitter diode to distinguish it from a receiving diode, called an IR receiver or IR receiving diode. (A Photo diode is a receiving diode). TV Remote Control Jammer Circuit diagram : There are so many IR emitters that we cannot put a generic number on the circuit to represent the type of diode. Some types include: CY85G, LD271, CQY37N (45¢), INF3850, INF3880, INF3940 (30¢). The current through the IR LED is limited to 100mA by the inclusion of the two 1N4148 diodes, as these form a constant-current arrangement when combined with the transistor and 5R6 resistor.