Frequency modulation fm is the standard technique for highfidelity communications as is evident in the received signals of the fm band 88108 mhz vs. Frequency modulation fm is where the output of one oscillator is used to modulate the pitch frequency of another. La72912v fm modulator and demodulator ic overview the la72912v is a fm modulation and demodulation singlechip ic. The main function of the voltage divided circuit is to let the negative voltage waveform of the 2206 ic operates normally. The oscillation frequency of 2206 ic is determined by resistor r i. Discussion following are the three frequency modulation fm concepts you need to remember. The xr2206 function generator circuit sinetrianglesquare waveform generator. Xr 2206 is an integrated circuit function generator. Generation of fm using xr 2206 chip to study the wave shapes, the basic idea behind using frequency modulation fm in audio sound synthesis was proposed by john chowning in 1973. The xr offers many possibilities fatasheet sine wave generation and modulation over a wide range of frequency. The output waveforms can be both amplitude and frequency modulated by. Ancient technology of making bamboo crafts most incredible bamboo woodworking ever duration. Angle modulation changes the phase of a signal as well as its amplitude, where amplitude modulation leaves the phase unchanged.
Frequency modulation objectives upon completion of this chapter, the student should be able to. The khz signal could be picked up on an am radio at the expected frequency, and the modulation heard. Armstrong, known as one of the founding fathers of radio technology, invented the superheterodyne radio receiver in 1918 and frequency modulation fm in 1933 1. Monolithic function generator xr 2206 the xr 2206 is a monolithic function generator integrated circuit capable of producing high quality sine, square, triangle, ramp, and pulse waveforms of highstability and accuracy. If m1 100 percent modulation with modulated frequency of 1khz sinusoid find the following. The output of the mc 1496 balanced modulator is proportional to the product of the two input signals. Internal led short circuit protection and autorestart timer can enabled by directly connecting the. Xr2206 function generator circuit electronics projects.
Connect to vref with a resistor to create active low fault signal output. This method is used by design team 5 from ece480 to build a radar system with rf components that has a frequency of 2. Bfsk modulation by using 2206 ic xr2206 ic is a waveform generator, which is similar to 8038 ic. Ic xr2206 datasheet pdf the xr is a monolithic function generator integrated circuit capable of producing high quality sine, square, triangle, ramp, and pulse waveforms. The carrier or sideband amplitudes are zero at some modulation indexes 20. The output waveforms can be both amplitude and frequency modulated by an external voltage. Connect directly to gnd to disable spread spectrum modulation of switching frequency. Frequency modulation fm is a process in which the carrier frequency is varied by the amplitude of the modulating signal i. Ic xr 2206 datasheet pdf details, datasheet, quote on part number. In figure 2, the resistor r3 and r4 comprise a voltage divided circuit.
Experiment 10 frequency modulation 80382206 youtube. Some phase modulation and quadrature amplitude modulation formats have a higher spectral efficiency for data transmission than frequency shift keying, a form of frequency modulation. In figure 1, resistors r2, r5 comprise a voltage divided circuit. Its main advantage is that it is more resistant to additive noise than am. Fm modulation and demodulation electrical and computer.
Out of many methods of frequency generation, this tutorial covers one of the simplest and most efficient circuits. Ask modulator circuit using ic 4066 ask demodulator using ic tl084. Instantaneous frequency the instantaneousfrequencyof cos. Xr description the is a monolithic voltagecontrolled oscillator vco integrated circuit featuring excellent. The output can be buffered to adjust its dc component and signal amplitude. Obtain a copy of the frequency domain display for further analysis. Function generator with xr modulating the frequency with an external signal has quite a few applications. Phase modulation is another type of angle modulation very similar to frequency modulation. Provides sine waveform output using ic 2206 having a frequency of 30 khz with amplitude adjustments of 5v pp. Reducing r to 2k gave an ideal 20 ms period, or 50 hz. Along with 555 ic timers, the circuit is designed around a wien bridge oscillator circuit and a clamping circuit. In modulation, one characteristic of a signal generally a sinusoidal wave known as the carrier is changed based on the information signal that we wish to transmit modulating signal.
The khz signal could be picked up on an am radio at the expected frequency, and the modulation. From its generation to modulation, the wave suffers. Formerly you will find the signal generator is called the function generator for use one. The ic mc 1496 is used as modulator in this experiment. Calculate modulation index, signal bandwidth, sideband frequencies and. However if st is sinusoidal, then the instantaneous frequency deviation of the anglemodulated signal is.
The bandwidth of an fm signal is proportional to the modulation index 21. The goal of this experiment is to become familiar with fm modulation and demodulation. From its generation to modulation, the wave suffers minimal. Frequency shift keying the xr 2206 can be operated with two separate timing resistors, r and r, connected to the timing pin 7 and respectively, as shown in. Chapter 8 frequency modulationfm fm was invented and commercialized after am. Polar view of digital iq modulation contd transmission signal is sine wave at frequency f 0 with information encoded in discrete values of amplitude and phase. You will also be able to describe phase modulation and a pm circuit. Figure 2 is the circuit diagram of the fsk modulator by using 2206 ic. Keywords modulate exert a modifying or controlling influence frequency modulation the modulation of wave by variation of its frequency. This tutorial explains circuit designing using a 555timer to generate a frequency modulated wave. In chapter1, we investigated the way of modulating a sinusoidal carrier wave using am technique. Its adjustment free modulation demodulation circuit significantly reduces the number of peripheral circuits required and can contribute to lower production costs. There are two ways to calculate the bandwidth of an fm signal. When you have completed this exercise, you will be able to describe frequency modulation and an fm circuit.
Mc1496d mc1496, mc1496b balanced modulators demodulators these devices were designed for use where the output voltage is a product of an input voltage signal and a switching function carrier. The xr 2206 is a monolithic function generator integrated circuit capable of producing high quality sine, square, triangle, ramp, and pulse waveforms of highstability and accuracy. For fm, the percentage of modulation is the ratio of the actual frequency deviation and the maximum allowed frequency. With this circuit the desired value of frequency modulation can be obtained easily by calculating the frequency of ic 555 in general, which is determined by the resistor 6. There is another way of modulating a, sinusoidal carrier wave, namely, angle modulation in which the angle of the carrier wave is varied according to the baseband signal. Pdf ak8125ae ak8125a 10pin 6mhz 92mhz 30khz ms1099e01 may10. Discuss the differences between am and angle modulation. Xr2206 datasheet monolithic function generator exar. Gnd to set the spread spectrum modulating frequency. Tps92692, tps92692q1 high accuracy led controller with. Mc 1496 is a monolithic integrated circuit balanced modulatordemodulator, is versatile and can be used up to 200 mhz. Frequency can be varied by a range switch and a potentiometer, so that one could make a fairly useful function generator based on this chip, at low cost. Typical applications include suppressed carrier and amplitude modulation, synchronous detection, fm detection, phase detection, and chopper.
Generation of fm using xr2206 chip to study the wave shapes. The oscillation frequency of xr2206 ic is determined by resistor r 1 and the resistor located at pin 8. Figure 1 is the circuit diagram of the ask modulator by using 2206 ic. The xr 2206 offers many possibilities for sine wave generation and modulation over a wide range of frequency. Am control must be used in conjunction with a, xr 2206 monolithic function generator general description the xr 2206 is a monolithic function generator inte grated circuit capable of. That could be the amplitude, phase, or frequency, which result in amplitude modulation am, phase modulation pm, or frequency modulation fm. The formula for the frequency is shown in the figure. Explain the advantages and disadvantages of the different analog modulation techniques. This lc meter allows to measure incredibly small inductances. You will use an oscilloscope and a multimeter to make measurements. The xr 2206 can be operated with two, amplitude modulation is approx imately 55db. Using the spectrum analyzer interface circuit, connect the output of the low level modulator with r4 removed and the modulation set to 50% at a frequency of hz. Circuit for pulse and ramp generation frequency shift keying.
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