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AM and FM - Difference
AM stands for amplitude modulation. It is the older technology for broadcast radio. In an AM signal, the carrier frequency is fixed and the information (audio or other signal) is transmitted by varying the magnitude of the carrier wave.
FM stands for frequency modulation. In an FM signal, the magnitude of the carrier wave is fixed and the information is transmitted by varying the frequency of the carrier.
An FM receiver can produce a better signal-to-noise ratio, since lightning and other electrostatic noises in the atmosphere can be mistaken for changes in amplitude of an AM signal, but do not resemble the changes in frequency in an FM signal. This led to FM being used increasingly for music broadcasts, where noise was particularly bothersome.
As it turns out, AM broadcast stations were also allocated limited bandwidth, which restricted their ability to transmit high-fidelity audio. FM broadcast frequencies were not so restricted. That meant that FM also had better audio bandwidth as well as better signal-to-noise ratio. However, that was a result of the technical decisions by the FCC (and its equivalent in other countries), not an inherent difference between AM and FM technology.
There are of course, additional modulation systems for each type of carrier, but that largely depends on the application.
Television (NTSC) uses both AM (picture) and FM (sound). HDTV uses digital modulation for both picture and sound.
Wiki User
∙ 7y ago
Wiki User
∙ 14y ago1.The difference between AM and FM is that AM stands for Amplitude Modulation while FM stands for Frequency Modulation.
2. Amplitude of FM wave is constant, It is independent of the modulation index. Where as amplitude of AM wave will change with the modulating voltage.
3. Transmitted power remain remains constant in FM, it is independent of mf. Where as in AM Transmitted power is dependent on the modulation index.
4. Fm receivers are immune to noise but AM receivers are not immune to noise.
5. It is possible to decrease noise in FM by further increasing the deviation. This feature is absent in AM.
6. BW is larger in FM, Thus wide channel is required. BW is much less than FM in AM.
7. In FM space wave is used for propagation. So, radius of transmitted on same frequency. Ground wave and sky wave propagation is used in AM. Therefore, larger are is covered than FM.
8. FM transmission and reception equipment are more complex. AM equipments are less complex.
Wiki User
∙ 12y agoFM covers more distance than AM :D
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What are the differences between AM and FM radio?
The main difference between AM and FM radio is the dial-in number and the amount of static each receive. AM radio preceded FM radio, with FM becoming popular in the 1950s.
What is the difference between FM 21-11 and FM 4-25.11?
FM 21-11 is numbered in the old system. FM 4-25.11 is numbered in the new system. The book is the same.
Difference between satellite radio and regular radio?
One of the main differences between satellite radio and FM radio is that there is a cost for satellite and FM is free. Satellite radio also does not operate using the same numerical AM and FM channels as FM radio.
What is the difference between narrowband FM and wideband FM?
wide-band is used for high quality transmission Narrow-band is used for speech & data k.vijayvardhanbabu
What is the difference between am raido and FM radio?
A: AM radio is an Amplitude Modulation transmission . Meaning it has fix frequency but it is modulated by the signal. FM Frequency Modulation the frequency is modulated by the signal
What are the differences between AM and FM waves?
There is no fundamental difference in the waves. It so happens that in the USA, commercial AM radio broadcasts in a frequency band around 1 MHz, and FM radio broadcasts in a band around 100 MHz, so their frequencies and wavelengths are different. But that has nothing to do with being AM or FM waves. The codes used to manipulate the waves in order to make them carry information are different for AM and FM, but there's no physical difference in the waves themselves.
What is the difference between a fifth generation iPod and an iPod Nano?
The 5th Generation has a video camera, FM radio, Pedometer, and a built in mic.
What is the difference between FM and PM?
FM - frequency modulationPM - phase modulation1. FMused to vary/change the instantaneous frequency of a carrier wave for transmission2. PMused to vary/change the instantaneous phase angle of a carrier wave for transmission
Difference between FM and PM?
frequency of the carrier is varied in accordance to the message signal in FM. Fm receivers are less complex. in Fm lower frequencies produce variation to the modulation index. phase of the carrier is varied in accordance to the message signal in PM. Pm receivers require proper synchronization so it is complex. Modulation index is independent of audio frequency
What does the number of a FM radio station mean?
The numbers in an FM radio station represent the frequency the station transmits the signal on. The frequency range for FM band radio stations is from 87.5 MHz to 108.0 MHz. These radio frequencies are considered VHF or Very High Frequency. The difference between AM and FM radio is that in AM radio the Amplitude is Modulated, or changed to send the signal, whereas with FM, the Frequency is Modulated or altered to send the signal.
What is the difference between FM transmitters?
Fro transmitting FM signals from one point to another,one need to have a full system that transforms your signal. The FM transmitter and FM modulator are two parts of this system and they are both necessary in making the system function as desired. The transmitter is the part that dissipates the FM signal into the air so that it can be received by antennas somewhere else. The FM modulator, on the other hand, is responsible for piggybacking the signal onto the carrier signal. Refer american-writers.org for more information.
What are FM waves?
FM radio uses frequency modulation to broadcast sound over radio. FM radio waves are usually transmitted between 87.5 to 108.0 megahertz.
