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Assuming you have the output of an AM modulated voltage hooked up to a properly matched antenna, you're really transmitting electromagnetic waves.
An electromagnetic wave, when intercepted by another antenna that is somewhat matched to the frequencies being used, induces a (tiny) voltage on that antenna that can be rectified, amplified, and turned back into sound waves on the receiving end.
What else can I help you with?
Why you need modulation?
It might be helpful to have a working definition of modulation before making a statement as to why it is needed. In fact, with an understanding of what modulation is, it will be obvious why it is included in electronic communications.Modulation is the "message" or the "intelligence" that is impressed on a radio frequency (RF) carrier. When we transmit a signal, we generate a carrier frequency, and then we modulate it. We "add" the message or the information we wish to transmit by modulating the carrier in some way. There are at least a dozen different modulation schemes ranging from simple to real head scratchers. They either modify the amplitude, the frequency or the phase of the carrier. Let's look at a few.The simplest modulation technique is taking the transmitted signal and turning it on and off. It is "keyed" to send a series of pulses. Morse code uses on-off keying. In this method of modulation, no modification of the RF carrier signal itself is made. It is simply switched on and off. (It could be looked at as amplitude modulation with the carrier either at zero amplitude or at "maximum" amplitude with nothing in between.) A series of pulses can be transmitted. With Morse code, a short "on" period will send a dot or "dit" out. If we extend the "on" period a bit, we can send a dash or "dah" out. Nothing real sophisticated here, but basic and effective communication. There are obvious limits to how fast information can be transmitted with this modulation scheme. (But don't tell the hams who still use it!)Most of us are familiar with AM radio. AM is amplitude modulation. The amplitude of the RF carrier is modified to modulate it. The amplitude of the modulating signal will determine the amount that the amplitude of the carrier is changed. (The volume of the modulation determines how much the amplitude of the carrier is changed. The frequency of the modulating signal determines the rate of change of the amplitude of the carrier. (The frequency of the modulation determines how fast the amplitude of the carrier is changed.). The frequency of the carrier is held constant through all this.How about FM? In frequency modulation, the amplitude of the carrier is constant. It's left alone. But the frequency of the RF carrier is changed. It is swung above and below where it sits (it's assigned center frequency) at a rate proportional to the frequency of the modulating signal, and at an amount proportional to the amplitude of the modulating signal. In FM single sideband, the carrier frequency and the frequencies above the carrier are transmitted and the frequencies below the carrier are suppressed (upper sideband transmission). Or the frequencies below the carrier are transmitted with the carrier and the upper frequencies are suppressed (lower sideband transmission). In conventional television, the video signal is single sideband, suppressed carrier. It's like "regular" upper sideband transmission except the carrier signal is suppressed. Sideband transmission "saves" space on the RF spectrum. And it works because we really don't need "all" of the FM signal to demodulate the signal at the receiver.Other forms of modulation become more complex. CDMA (code division multiple access), TDMA (time division multiple access) and other methods are used in cell phones to modulate the carrier so the digital data stream can be impressed on the carrier.Modulation is the addition of intelligence to a carrier signal. It's the message. Modulation is necessary because the point of communication is getting the message through.A Simple answer:Simply this... Any communications medium: e.g. Free space - radio waves, Air - Sound waves or radio waves, Optical Fibre - Light, Copper Wires Electrical Anergy (with frequency limits of the copper wire construction) is made for a certain type of signal. But if the signal we want to send is not compatible with the medium, then it does not travel well.Modulation changes the information we want to send from it's original form, into one that is more compatable with the medium we are trying to use.For example, your computer speaks digital over a TCP/IP LAN which requires CAT 5 or better rated cables,, but to connect to your internet service provider (ISP), you need to send the signal over the wires of the telephone company (made for voice tones). To make this connection, and ADSL modem (modulator/demodulator) is used to convert the data into audio tones, which pass over the telephone line, and at the far end are converted back to digital to join the service providers network. in the reverse direct the ISP does the same, and the signals are de-modulated, back to data for your network.Or in simple terms, Its about best use of the medium. Everything else is just a away of doing it. And there are a lot of possible ways to choose.
Why is the single sideband suppressed carrier version of amplitude modulation is not used for the sound broadcasting and television broadcasting?
A single sideband receiver have a BFO (Beat Frequency Isolator) that is generating the other half side of the original audio. The BFO is hand tuned to clarify the audio to, as close as possible to the original sound. An automatic clarifier is not really possible therefore music and voices never sound the same as the original.
What is the voltage used for ignitor in boiler?
It really depends on the size but the average is about 24 volts.
Do appliances run on current or voltage?
This is a 'chicken and egg' situation. The motors in washing machines, etc., are driven by current but, without voltage, current cannot flow. You can't really separate the two.
What is the line voltage of a 230000 kv transmission line?
Transmission and distribution voltages are normally expressed in terms of line voltages, so the answer is that the figure you quote is a line voltage. Incidentally, do you really mean 230 megavolts for a transmission voltage?? And the symbol of kilovolt is 'kV', not 'kv'.
What is one disadvantage of an amplitude modulation communication system?
One disadvantage of the standard amplitude modulation system is that 67% of the power is used for the carrier, but the carrier transmits no information, so it can be considered as wasted power.The 34% remaining power is split between two mirror opposite sidebands so, in effect, you really only have 17% of your power used to carry the signal.
How area of solar panel affect voltage?
It is not based on the area really... basically for each photo voltaic cell they have a certain voltage, if you connect them in series such as -------0-------0----------0---------0--- then it will increase the voltage 4fold but not the amplitude if they are connected in parallel then amplitude will increase but not voltage. Usually panels have a mix of both to get a good voltage and amplitude |--------0-----| |--------0-----| |-------0------| |------0-------| |------0-------|
What is the amplitude of a violin?
im really not sure...is it...um....quiet comparing to the amplitude of a guitar...i think
What is the amplitude of the violin?
im really not sure...is it...um....quiet comparing to the amplitude of a guitar...i think
Does intensity increase with the amplitude of a sound wave?
Yes, generally, intensity does increase with the amplitude of a sound wave. The intensity of a sound wave is directly proportional to the square of its amplitude. This means that if the amplitude doubles, the intensity will increase by a factor of four.
The loudness of a sound wave is determined by its?
By its amplitude. Really loudness is sound intensity & intensity depends on square of amplitude ie. higher the amplitude higher the intensity which means higher the loudness.
Why is modulation necessary in signaling?
If you didn't have modulation it'd be the same signal going out the whole time, like a continuous tone - which can't really tell you that much. By modulating the signal you can say much more.
Why you need modulation?
It might be helpful to have a working definition of modulation before making a statement as to why it is needed. In fact, with an understanding of what modulation is, it will be obvious why it is included in electronic communications.Modulation is the "message" or the "intelligence" that is impressed on a radio frequency (RF) carrier. When we transmit a signal, we generate a carrier frequency, and then we modulate it. We "add" the message or the information we wish to transmit by modulating the carrier in some way. There are at least a dozen different modulation schemes ranging from simple to real head scratchers. They either modify the amplitude, the frequency or the phase of the carrier. Let's look at a few.The simplest modulation technique is taking the transmitted signal and turning it on and off. It is "keyed" to send a series of pulses. Morse code uses on-off keying. In this method of modulation, no modification of the RF carrier signal itself is made. It is simply switched on and off. (It could be looked at as amplitude modulation with the carrier either at zero amplitude or at "maximum" amplitude with nothing in between.) A series of pulses can be transmitted. With Morse code, a short "on" period will send a dot or "dit" out. If we extend the "on" period a bit, we can send a dash or "dah" out. Nothing real sophisticated here, but basic and effective communication. There are obvious limits to how fast information can be transmitted with this modulation scheme. (But don't tell the hams who still use it!)Most of us are familiar with AM radio. AM is amplitude modulation. The amplitude of the RF carrier is modified to modulate it. The amplitude of the modulating signal will determine the amount that the amplitude of the carrier is changed. (The volume of the modulation determines how much the amplitude of the carrier is changed. The frequency of the modulating signal determines the rate of change of the amplitude of the carrier. (The frequency of the modulation determines how fast the amplitude of the carrier is changed.). The frequency of the carrier is held constant through all this.How about FM? In frequency modulation, the amplitude of the carrier is constant. It's left alone. But the frequency of the RF carrier is changed. It is swung above and below where it sits (it's assigned center frequency) at a rate proportional to the frequency of the modulating signal, and at an amount proportional to the amplitude of the modulating signal. In FM single sideband, the carrier frequency and the frequencies above the carrier are transmitted and the frequencies below the carrier are suppressed (upper sideband transmission). Or the frequencies below the carrier are transmitted with the carrier and the upper frequencies are suppressed (lower sideband transmission). In conventional television, the video signal is single sideband, suppressed carrier. It's like "regular" upper sideband transmission except the carrier signal is suppressed. Sideband transmission "saves" space on the RF spectrum. And it works because we really don't need "all" of the FM signal to demodulate the signal at the receiver.Other forms of modulation become more complex. CDMA (code division multiple access), TDMA (time division multiple access) and other methods are used in cell phones to modulate the carrier so the digital data stream can be impressed on the carrier.Modulation is the addition of intelligence to a carrier signal. It's the message. Modulation is necessary because the point of communication is getting the message through.A Simple answer:Simply this... Any communications medium: e.g. Free space - radio waves, Air - Sound waves or radio waves, Optical Fibre - Light, Copper Wires Electrical Anergy (with frequency limits of the copper wire construction) is made for a certain type of signal. But if the signal we want to send is not compatible with the medium, then it does not travel well.Modulation changes the information we want to send from it's original form, into one that is more compatable with the medium we are trying to use.For example, your computer speaks digital over a TCP/IP LAN which requires CAT 5 or better rated cables,, but to connect to your internet service provider (ISP), you need to send the signal over the wires of the telephone company (made for voice tones). To make this connection, and ADSL modem (modulator/demodulator) is used to convert the data into audio tones, which pass over the telephone line, and at the far end are converted back to digital to join the service providers network. in the reverse direct the ISP does the same, and the signals are de-modulated, back to data for your network.Or in simple terms, Its about best use of the medium. Everything else is just a away of doing it. And there are a lot of possible ways to choose.
What is the Amplitude of laser?
The amplitude of a laser refers to the maximum strength or intensity of its electromagnetic waves. It is a measure of the peak value of the electric and magnetic fields in the laser beam. The amplitude of a laser can affect its power output and the characteristics of the light it emits.
What does am stand for in reference to radio?
Amplitude Modulation, this is the standard Am broadcast band from 540-l600 KHZ or Kilocycles as was the older term, Called also Longwave, as opposed to shortwave, sometimes in Europe High Am band(like say l0l0 Wins in NYC) is considered Medium Wave in radio parlance. Quite distinct from FM which is , of course Frequency Modulation and is tops for fidelity and clarity of tone- good for music and also used for TV Sound! FM really is the Top End, to borrow the popular phrase.
How does the output voltage of the VFD change if the DC bus voltage level is fixed?
The VFD outputs pulses at the DC bus voltage. Each pulse is from the DC bus and the voltage does not change. It is the average voltage that changes because the VFD changes the on and off times of these pulses. For a lower average ac voltage to the motor, the ON time is small and the OFF time is large. The VFD actually pulses about 4000 times per second, so the motor does not really know these are just lots of quick DC bus voltage pulses. To simulate an ac waveform, the VFD uses pulse-width modulation which means the pulse ON time at the peak of the simulated sinewave is longer, or fatter, than the pulses where the simulated sinewave is closer to 0 crossing.
What does positive 20mv mean?
Probably 20 millivolts above zero voltage. A really weak voltage.
