The basic small-range remote controls are 2, Infrared and RF (Radio Frequency). One of the weaks of Infrared is that the signal can not pass the walls. So, if you wantto control your garage door, the only way is to use some RF remote control. The circuit (transmitter and receiver) uses few components and ordinary (I love few component circuits). It`s easy to be built because you don`t
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have to tune-up any coil or variable capacitor. The RF modules are fix to work in 418MHz area. b. ) and thepower-saving of thetransmitter. Atransmitter must havelong battery life. It`s not the bestchoice for youto change the battery every 3 days ;). I don`t care about the receiver`s power supply, because receiver must beworking all the time. The transmitter is constituted by AT90S2323 microcontroller and TLP-418A RF transmitter module that works at 418MHz. I have designed the transmitter for more battery conservationand safe transmission of the data. The battery conservationwas madeby using thepower-down mode of AVR. In this case the AVR goes to sleep with less than 1uA (microampere) current and wait for external interrupt on pin PB1 to awake from sleep mode and continue operating. If you press the S2 key, the logic of this pin goes to `0` (0V) and AVR awake from the sleep mode (because PB1 is INT0) andcheck if pressed the S1 key. If not, the AVR take as pressed key the S2. If yes the AVR take as pressed key the S1. Then, it calculates the checksum and transmits 4 times the same 4byte sequence to make sure that receiver will take the data and goes to sleep mode until next interrupt on PB1 pin. The transmitted data has4 bytes length and is transmittedwith2400 bps (bits per seconds). The 1st and 2ndbyte are for the recognition of a valid remote control from the receiver (like ID bytes), 3rd byte is thecommand byte. The relays...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
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The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
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This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
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