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What else can I help you with?
Why do you need a carrier wave?
In radio transmission, you could theoretically transmit radio signals at audio frequencies. However, because the wavelength of electromagnetism at audio-like frequencies is Huge and the frequency of a radio transmitter dictates the size of the antenna and the power requirement, you would need A Very Big Antenna and a Very Big Power Supply to do this. So, we've learned to transmit at higher "carrier" frequencies, modulating either the amplitude or frequency of the carrier signal with our audio and subtracting the carrier at the receiver end.
What is carrier frequency?
A carrier frequency is a single radio frequency with steady amplitude. Alone, it would sound like silence on a receiver. This is the frequency that a radio receiver is tuned into. To be of use in communication, this carrier wave has to be changed in time with another signal (usually audio), called 'Modulation' It can be turned on and off using a Morse key. It can be changed by shifting the frequency, FM. It can be changed by varying the amplitude, AM. It can be changed by adding or subtracting audio to the carrier. Single Side Band. It can have data applied by shifting between two carrier frequencies. FSK. (Frequency shift keying.) It's called a carrier, because it is the carrier of information without necessarily being the information itself.
Does optical need to be hooked to receiver as the HDMI cable to tv?
Depends on the receiver. Some models have just a pass thru feature and connot decode the audio portion of the HDMI signal, and therefore will need a digital audio cable to get sound. Some receivers can decode the audio, so you will need to consult your manual to see what they say. If you need a audio cable it will tell you.
What is the envelope of a signal?
The envelope of a signal is the "apparent" signal seen by tracking successive peak values and pretending that they are connected. Normally, this question involves amplitude modulation of a radio frequency carrier by an audio frequency signal. The two frequencies involved are very much different - 20 kHz versus 1 mHz, for instance, and this "envelope" effect will be very noticable on an oscilloscope.
Block diagram of amplitude modulation?
The basic block diagram consists of a modulator which may be a product modulator or a balanced modulator. The audio input signal is fed to the input of the modulator and there it is being multiplied by the carrier signal which is generated by using a oscillator. This block diagram in its crude form is given by:
What is over-modulating condition in term of amplitude modulation?
When your audio modulating signal is larger than your RF carrier amplitude the peak of the modulated carrier will become flat and a distorted audio signal with flattened peaks will be send out from the detector on the receiver side
What is the effect of carrier frequency variation on AM signal?
If the modulation is to large your bandwidth will be to wide in other words the frequency shift will be larger than normal that will result in a distorted audio signal at the receiver
What is a carrier reinsertion oscillator?
A carrier reinsertion oscillator is an electronic circuit used in a radio receiver that is designed to receive single side band carried suppressed radio transmissions. As suggested by the name, in a single side band carried suppressed signal, the carrier signal is suppressed (not transmitted) to save power and/or bandwidth. Before the single side band carried suppressed signal can be decoded to extract the original audio signal, the carrier must first be reinserted. This must be done accurately, otherwise the recovered audio signal will be unintelligible.
What is a carrier and how does it affect what you hear on the radio?
A carrier is a high-frequency signal that carries information on a radio wave. The carrier frequency is modulated to encode audio signals, which are then transmitted and decoded by the radio receiver to produce sound. The carrier frequency determines the station you're tuning into on the radio.
Why is amplitude of demodulated FM signal much less than modulated signal?
because demodulated FM is an audio signal, which the frequency is much smaller that is why it can be transmitted alone. It need carrier which has large frequency. Modulated signal is an audio signal + carrier that is why the amplitude is higher.
What is the frequency and wave form of old land line phone carrier?
First answer.The landline phone has no carrier frequency it is a baseband signal with a 3KHz bandwidth.Correction:So there is a signal that can handle a 3KHz bandwidth, what do you call that signal? I call it a carrier, if you don't have a carrier, you will need to amplify the audio every 30 meters else you will end up with no audio at the end of the line. So there is a carrier on all phone lines. Note the carrier signal are up to 90 VPP and is AM modulated at the instrument, but in digital systems the carrier are switched on and of, FSK modulation.
Why do you need a carrier wave?
In radio transmission, you could theoretically transmit radio signals at audio frequencies. However, because the wavelength of electromagnetism at audio-like frequencies is Huge and the frequency of a radio transmitter dictates the size of the antenna and the power requirement, you would need A Very Big Antenna and a Very Big Power Supply to do this. So, we've learned to transmit at higher "carrier" frequencies, modulating either the amplitude or frequency of the carrier signal with our audio and subtracting the carrier at the receiver end.
How does the intelligence signal modulates the carrier?
There are three major types of modulation:AM, Amplitude Modulation, where the modulation signal is altering the amplitude of the carrier according to its own amplitude, normally this is done in the output stage. Therefor a strong audio signal is necessary at the same or a little less than the power of the carrier, never higher, because that will over modulate the carrier that will resort in distortion of the receiver output. AM is used in the lower band of the RF spectrum.FM, Frequency Modulation, where the frequency of the carrier is altered by the audio signal. When the amplitude of the audio is going higher the frequency go lower. Modulation happen at the oscillator stage, therefor a small audio signal is used to modulate the frequency. FM is normally used in the higher frequency range of the RF spectrum, 50MHz and up.FSK, Frequency-shift keying, used for data transmission, this type of modulation is simply, switching the carrier on and of, a high bit will switch the oscillator on and a low bit will switch it off, in some designs a low will be on and a high off.
With regard to FM signal modulation how will a decrease in modulation voltage affect the FM signal spectrum?
Answer: A decrease in the audio voltage will resort in a to narrow band and will be difficult for the receiver to detect the audio.
How does FM transmitter work?
An FM transmitter works by modulating a carrier wave's frequency in accordance with an audio signal. The audio input is converted into an electrical signal, which then alters the frequency of the carrier wave. This modulated wave is transmitted through an antenna, allowing it to be picked up by FM receivers within its range. The receivers demodulate the signal back into audio, enabling sound playback.
What is a optical audio cable used for?
An optical audio cable is used to transmit digital audio (AC-3) signal from the source to the receiver, such as from a DVD player to a digital audio amplifier/receiver. You can transmit 5.1 dolby digital or DTS surround sound with an optical audio cable, same as digital coaxial audio cable.
What is the function of a mixer of an AM receiver?
The mixer in an AM receiver combines the incoming radio frequency (RF) signal with a local oscillator signal to produce an intermediate frequency (IF) signal. This process allows for easier amplification and filtering of the desired audio signal, as the IF is typically at a lower frequency. The mixer effectively translates the high-frequency AM signal down to a more manageable frequency for further processing, enabling clearer audio reception.
