What is the difference between heterodyning and superheterodyning?
When you combine signals of the same or different frequencies. The resulting energy will be each original frequency and the sum of the frequencies and a frequency that is the difference of the two signals. This is the basis of heterodyning. This allows us to take an information signal and "upconvert" it to the RF realm for transmission. But the same processes can be used to "downconvert" or to beat one signal against the other to get a lower frequency representation of the energy. After hererodyning came out, newer radios were sold as superheterodyning as a marketing ploy. Sorry, but it is not more complex than that. This was back in the early 20th century and the idea of fair marketing or truthful processes were not legal issues like today. Have a nice day. Bob
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A superheterodyne receiver is a Radio Frequency receiver method that multiplies the received signal frequency with a local oscillator frequency to get frequencies that are the… sum and difference of the 2 frequencies. For example, if the received signal is 5MHz and the local oscillator frequency is 4MHz, they are multiplied together. 1MHz and 9MHz frequencies would be gotten. Usually the 1MHz is the Intermediate Frequency (IF). It will be admitted (through a band pass filter) later passed through the required electronic circuits for proper processing.. There is also the method of the Variable Tuned Filter.
A superheterodyne receiver is a receiver that maximizes both sensitivity and selectivity. Normally, these are conflicting goals, and in a single stage, you can only get one, b…ut not both. The difficulty is that you cannot build a high gain RF stage with enough selectivity to reject adjacent signals. The superheterodyne process solves this problem. First, the RF stage is built for high gain, but it is not very selective. It might have some tunability, i.e. selectivity, but that is not its primary objective. Second, there is a local oscillator that is tuned to a frequency some distance away from the primary signal's carrier. In a standard AM receiver, that distance is 455 KHz; in a standard FM receiver, that distance is 10.7 MHz. Third, the amplified RF signal and the local oscillator are mixed together. Recall from Fourier analysis that when you mix two signals together you get four signals; the two original signals, their sum, and their difference. We are interested in their difference. Basically, the output of the mixer contains the original signal downshifted to either 455 KHz or 10.7 MHz. Fourth, we have an IF stage that is tuned around 455 KHZ or 10.7 MHz. The IF stage is highly optimized for operation at one range of frequencies, and can therefore be highly selective. Usually, the IF stage is three bandpass filters, each tuned slightly differently, so that the end result is a bandpass filter that is wide enough to pass the entire bandwidth of the original signal, 20 KHz for AM and 100 KHz for FM. Fifth, we have the demodulator. At this point, we retrieve the signal and either just amplify it (AM) or further decode it for stereo (FM). The end result is that we got sensitivity in the RF stage and selectivity in the IF stage, along with tunability in the local oscillator. That is the superheterodyne process. A very common type of radio receiver. The output from a simple radio aerial will be of the order of a microvolt or so, and the output desired is a few volts. So an amplification of a million or so is needed. This is achieved by multiple stages of amplification - each generally of less than 100 times. And we need to be able to tune over a range of 3:1 for the Broadcast Band, and perhaps greater for some other bands. For technical reasons concerning the mechanics of tuning, this is more easily achieved at a single frequency - typically about 0.5 MHz. The alternative would be to have the same number of stages of amplification but each with its own tuning. Mechanically much more difficult. So, the incoming signal from the aerial is mixed in a mixer stage , along with an internally generated signal. [This mixer stage is a non-linear process, and as a result, produces a complex output, of both the input frequencies, the sum of them, and the difference between them. ] The difference frequency is selected - the 0.5MHz above. So the mixer stage is followed by several intermediate stages of amplification operating at the 0.5 MHz, - where most of the amplification takes place. This is then followed by a demodulator (detector) stage , which separates the audio signal from the carrier signal. And followed in turn by an audio amplifier stage which feeds the loudspeaker. The 'hetrodyne' part of the name refers to the mixing of the signals at the mixer stage. For radios operating at higher frequencies than the broadcast, the Intermediate stage will commonly operate at 10MHz or so.
heterodyne fiber optic system?
"Different from" is the correct term. "Different to" is simply acommon grammatical error. Things are "different from" or "similarto".
the first account number differs in one number with the second one
Superheterodyne receiver is a case that is vital, that takes expert attending regarding
can a superheterodyne receiver generated high noise
Different is a describing word/adjective. Difference is a noun.
The model A-33 RCA is 1939-40
When two frequencies are "mixed" the sum and the difference frequencies are produced. These frequencies are called heterodynes. If these frequencies are outside the range of h…uman hearing they are said to be supersonic. The full name of a superhet receiver is supersonic heterodyne. This receiver uses a mixer to produce an intermediate frequency outside the range of human hearing. Before superhets were in common use, but following from the old crystal set was an amplified form of the crystal set, called the 'Tuned Radio Frequency" receiver, or "TRF" for short. With many TRF receivers, a control called 'regeneration' controlled the gain of the RF amplifier, and could be turned up to the point that the entire radio set became unstable and oscillated, usually at the frequency you were tuned to. With the gain set just below the point of oscillation, these receivers were very sensitive. For listening to morse code signals, the control would be advanced just into the oscillation stage, and the difference in frequency between the received signal and the receiver's oscillation became a 'beat note', or a beeping sound, that was easy to receive in noisy conditions. This form of reception became known as 'heterodyne reception', and this type of radio was called a 'regenerative receiver'. Problem was, this operation usually required 3 hands, a still room and a lot of patience. Once tuned, the radio would drift in frequency, or burst into loud screaming oscillation, seemingly for no apparent reason. Sometime later, the 'super-regenerative' receiver was developed in an effort to simplify operation and these were used up into VHF frequencies into the early '30's. Eventually, with the development of better radio tubes and more elaborate design, the suphet rapidly became the most popular, as it was so easy to use. At last, you only needed one hand to operate a radio. And you could walk away and come back and it was still tuned to the station. This was the '30's where radios found their way into every westerner's living room, bringing news and entertainment to the masses (that could afford it). By the 60's, we all had 'transistors', and the superhet was everywhere. Now, most of us have TV, cable or satellite. And you know which process they all still use to turn the RF signal into a video signal that the screen can display? Just testing!
its a radio! :D
Superheterodyne is: . more sensitive than TRF . more selective than TRF . easier to tune than TRF . eliminates the squeal that sometimes happens with TRF . is easier to …adapt to FM and TV reception than TRF . can be adapted for use with microwave signals to up/downconvert . etc.
Eg.There is a big difference between night and day / everyone dresses differently
for better output,and low impedance.!@
One phrase is correct and one is not correct. no difference and not different Both phrases have the same meaning difference is a noun and different is an adjective.
The superheterodyne converts the desired incoming signal frequency to an (usually lower) intermediate frequency before demodulating it and extracting the audio signal (or vi…deo/data, etc). The neutrodyne is a tuned radio frequency design where all amplifying stages operate at the incoming signal frequency. This was the commonest design up to the 1930s. The triode amplifiers used suffered from signal feedback, where a signal from the amplifier's output was coupled back to its input. This could cause the amplifier to act like a transmitter and to oscillate. Neutralization (with capacitors) was invented to prevent this problem and the circuit was named the "neutrodyne".
The original heterodyne detector was pioneered by Canadian inventor Reginald Fessenden in 1905, but it was not pursued far. The vacuum tube electronic oscillator would not …arrive until 1912. The autodyne receiver, which has one stage function as both a local oscillator and a heterodyne mixer, had several inventors around 1912 to 1913. The superheterodyne principle was revisited in 1918 by U.S. Army Major Edwin Armstrong in France during World War I.