Remote Control

This is an image Schematic. No Description available.

The CIR, Computerized Infrared Remote, is a very simple device for recording and playing back streams of infrared data, in particuliar the codes transmitted via remote controls. It consists of two sections: a receiver to capture an incoming IR data stream, and one or more transmitters to resend the data stream under computer control.

The CIRThis article will show you how to build your own version of the Fire-Stick infrared remote control system. The Fire-Stick has been an extremely popular, and HOT selling item here at Rentron.com for quite a long time. The LITEON infrared receiver modules originally designed-in to the Fire-Stick have been discontinued, and forced us to re-design the original circuit boards.

This is a very simple RF transmitter circuit that consists of the Holtek HT-12E encoder chip and AM 418MHZ-transmitter module (WZ-X01). Using the hybrid RF xmit/receive modules make building the RF remote control a lot easy. The transmitter can be powered with any voltage from +3 to +12V. The recommended oscillator is Foscd (decoder) = 50 Fosce (encoder). See data sheet for more details. The circuit diagram for the receiver (WZ-R01)is shown in figure 2. The decoder U1(HT-12D) receives serial addresses and data from the encoder that are transmitted by the RF transmitter module.

Due to the huge interest in this project, I have just recently finished the NEW schematics. The older schematics were scanned and pretty poor quality. These new ones should make it considerably easier to recognize the parts used for the project. The Ming RF transmitter and receiver boards used for this project are relatively inexpensive and perform admirably considering the meager price. Using the quarter wave antennas, I have had some excellent results with operating distance as well as overall operation.

You can use a single-supply system to precisely measure the temperature at a remote location with less than 1°C error over a 0 to 100°C range (Figure 1). The circuit includes T1, a low-cost AD590 temperature sensor; IC1, an AD8541 rail-to-rail amplifier; four resistors; a trimming potentiometer; and an ADC. You can omit the ADC if you need an analog output. You could replace the trimming potentiometer with an AD8400 or AD5273 digital potentiometer for easier calibration.

The remote control receiver is a custom design based on a pre-built 433MHz UHF radio receiver, a decoder chip and a BASIC Stamp. The Stamp is expensive, but easy to work with. The receiver requires 8.5mA, plus 1.5mA for each LED (individual or segment) that is lit for a maximum of up to 23mA. In practice it is between 13 and 16mA. Pressing a button on the remote transmitter causes the receiver to consume an extra 0.2mA. In the 'power saving' mode the PBASIC 'nap' instruction is used in combination with turning all the LEDs off to reduce power consumption to 4mA. The battery should last about 30 hours of on-time.

With a handful of inexpensive components, a little creativity, and the power of PicBasic, you can build some pretty outstanding robotics creations as Rob Arnold proves with his Ruf-Bot project. RF remote control is just way too cool not to use in your designs, but if you're a newbie like me it's difficult to successfully build solid RF transmitters and receivers on your own. When I started out I didn't realize that the larger breadboard I was working off of was causing a lot of the signal deviance because the metal traces on the breadboard worked like small capacitors, and changed my circuit dynamics.

These units can be useful as a short-range, single-channel remote-control. When the pushbutton in the transmitter circuit is briefly activated, the LED D1 in the receiver illuminates and an optional beeper or relay can be operated. Circuit operation is based on a non-modulated 35KHz frequency carrier transmitter, and on a high-gain two-stage 35KHz amplifier receiver, followed by a frequency-voltage converter and DC load driver.

This is a simple, cheap device that can be connected to any serial port to control most components that have infrared remote controls. I designed and built it (on a solderless breadboard) in 1991. In 1992 I wrote a lengthy description of it for an electronics class. In 1994 I finally designed a PC board for it, using a free, X-based PC board design program called pcb, and in 1995 I etched several of the boards and made the final product.

Infrared remote controls are using a 32-56 kHz modulated square wave for communication. These circuits are used to transmit a 1-4 kHz digital signal (OOK modulation) through infra light (this is the maximum attainable speed, 1000-4000 bits per sec). The transmitter oscillator runs with adjustable frequency in the 32-56kHz range, and is being turned ON/OFF with the modulating signal, a TTL voltage on the MOD input. On the receiver side a photodiode takes up the signal.

In many embedded or control applications, you might prefer to use a small, customized keypad with your PC-based system rather than a full-fledged alphanumeric keyboard. You may also need to locate the keypad some distance from the system hardware. If you have no parallel ports available for this purpose, you could use a standard RS-232C port.

Here is a handy gadget for test- ing of infrared (IR) based re- mote control transmitters used for TVs and VCRs etc. The IR signals from a remote control transmitter are sensed by the IR sensor module in the tester and its output at pin 2 goes low. This in turn switches on transistor T1 and causes LED1 to blink. At the same time, the buzzer beeps at the same rate as the incoming signals from the remote control transmitter.

If you face the challenge of adding a second, independently controlled light source to an existing ceiling lamp controlled by a wall switch, you may find that stringing a second power line is impossible. First, you can replace the wall switch by the circuit in Figure 1. Pushing the on switch S1 or S2 for approximately 1 sec inserts the 12V zener diodes D1 or D2 in series with the hot wire of the power line.

The circuit described here can be used to switch up to nine appliances (corresponding to the digits 1 through 9 of the telephone key-pad). The DTMF signals on telephone instrument are used as control signals. The digit ‘0’ in DTMF mode is used to toggle between the appliance mode and normal telephone operation mode. Thus the telephone can be used to switch on or switch off the appliances also while being used for normal conversation.

The heavy-duty switching device in Figure 1 counts the number of products manufactured and rolled out of a production line per hour. The switch is useful for counting rolling heavy objects or materials weighing one to several thousand kilograms. It generates one pulse per product (no false outputs generated) and provides a count rate as high as 3600 parts per hour. The switch uses a low-cost, commercial, piezoelectric gas lighter, commonly used for kitchen or gas-grill burners.

Measuring temperature at a remote location is a common requirement, but the implementation is usually not straightforward. Most temperature sensors have a voltage or current output, which, to minimize noise pickup, should undergo conversion to digital form near the sensor. Thus, an ADC, a digital interface, and a power supply must all be situated at the temperature-measurement point.

This infrared light controlled 12-tone musical bell can be operated using any TV remote control. It can be operated from up to 10 meters, provided the remote control is directed towards the sensor.

This project will show you how to build a circuit to control things remotely using the the Basic Stamp II and Ming RF modules. I am making a remote engine starter for my truck, but anything you can turn on and of with a Relay could be used in this project. Without any type of anttena the Modules can get 50 to 100 foot range, which is excellent considering there only 10 bucks each. However with a antenna much better range can be achieved.

Up to 15 Transmitter units can be learnt by one Rx unit. (The article says 16 but the technical manual says 15.) Press button 1 (the button all by itself) while simultaneously pressing the LEARN tact switch on the main board. You only have to do this briefly for under a second. But note it takes about 15 seconds for the two units to internally connect and recognize each other. (During this 15 seconds it seems that one and only one keypress of the Tx unit will be recognised. Just disregard this. Wait the full 15 seconds until the two units have connected.