The transmitter function is to modulate the original signal frequency of the signal carrying the message, the process is called modulation, the circuit realization of this function is called frequency modulation circuit. al of the circuit. FM tuner is divided into direct and indirect modulation types. Direct FM modulation signal is directly controlled from the oscillator circuit parameters and
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operating status, so the oscillation frequency by the modulation varactor diode frequency modulation, frequency modulation and relaxation reactance tube FM oscillators fall into this category. Klystron as the microwave frequency band commonly used devices. Integral circuit indirect FM is the modulation signal points so that the output amplitude is inversely proportional to the modulation angular frequency, then the phase modulation of the phase modulation device, then the output phase modulation is required for FM signals. FM has the advantage of an indirect carrier frequency is relatively stable, but more complex circuit, frequency shift is small, and large parasitic amplitude modulation, it normally takes several times to increase frequency to frequency shift. The basic requirements of the tuner is adjusted frequently move large frequency characteristics of a good, small parasitic amplitude modulation. Widely used in FM radio tuner, TV audio, microwave communications, phase-locked circuits and other electronic equipment Sweep. FM radio has a strong anti-interference performance, sound clarity, etc. , gained rapid development. FM radio frequency band is usually about 200 ~ 250kHz, the band width is ten times the number of AM radio, easy to send high-fidelity stereo signal. The amplitude by the bandwidth limitations, there is in the receiver passband width and interference conflicts, so the audio signal is limited to 30 ~...
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....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
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....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
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....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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