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Why would one want to deliberately reduce the Q of the tuned circuits of the intermediate frequency amplifier stages of a receiver?
EcclesJordanTrigger
Because if the Q is too high the bandwidth available for the signal will not be adequate. The passband of the IF amplifier requires steep sides to reject interference, which requires several tuned circuits, but the bandwidth is set by the type of signal being passed, e.g. 3 kHz for a voice communications circuit, 9 kHz for AM radio or 20 kHz for high-quality radio.
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What circuits cannot be implemented on fpga?
Analog circuits like amplifier are all cant be implemented
What waveform is best and why?
different waveforms are used for different purposes i.e a sinewave can be used to test the frequency response of an audio amplifier or act as a 'trace' signal to find a fault in an audio amplifier. Square waves can be used in digital circuits as a pulse or as a binary code.
What is negative feedback in an amplifier?
feedback that reduces gain to help stabilize amplifier operation. gain is easy and cheap to get, stability isn't. its a tradeoff. so amplifier is deliberately designed with much more gain than needed and negative feedback sacrifices some of that gain to stabilize it.
Where is an IF amplifier used and why?
IF stands for intermediate frequency, an IF amplifier would typically be used in radio circuits. To help explain this, lets start with a model of a superheterodyne AM receiver. All the carrier frequencies the radio is capable of receiving comes through the internal ferrite antenna. The signal may be weak, so there is an RF amplifier to boost the signal. That signal is still far from what we need. Sure we could try to employ a detector stage to filter the amplitude shifts from the carrier, but the quality would be poor. Transistors don't work as well at very high frequencies. Plus, if the receiver is tunable, it can be difficult to tune all the filters, amplifiers, and detectors in unison. And selectivity can be a challenge. Higher frequency tuners take up more bandwidth, making it harder to tune closer signals. But there is a way to work around all of these challenges. What if you could convert all the other carrier frequencies to a single, lower frequency regardless of where the radio's dial is set, and then have the rest of the circuits tuned to work with that lower frequency? So that requires employing a local oscillator. Then you can use a dual gang variable capacitor to tune both the RF frequency and the local oscillator frequency. Then the RF frequency and the local oscillator frequency are both mixed together using the heterodyne principle to form a third frequency called the Intermediate Frequency, or IF. Actually 2 new frequencies are created (the sum and difference of the two original frequencies), and filters are used to allow only one of those through, and in this case 455 KHz is standard for an AM radio (and 10.7 MHz for FM). Then you would amplify this new frequency using an IF amplifier. There may be an additional filter after the IF amplifier stage to keep it steady at the standard IF frequency. Then from there is the detector stage which is extracts the information carried on the IF from the IF, leaving the audio frequency. There may be a preamp stage at this point, and it may receive reverse bias from the RF stage, allowing the preamp to compensate for different signal levels. Then from there is the driver amplifier stage which is what drives the speakers. So the IF amplifier is used to help convert the RF frequencies to a single intermediate frequency while keeping the information that is modulated on the carrier. That simplifies the circuitry, allows for less expensive components to produce quality output, and provides better selectivity. This method is used in other places too, such as with satellite and digital television. In the case of satellite, there is no way to use ordinary coax cable unless an intermediate frequency is used, hence the dual LNB converter which converts a 10.7-12.75 GHz signal into a 950-2150 MHz signal. Then from there, the set top box converts it to 480 MHz. Also, the music instrument called a theremin uses a local oscillator to make the tone more stable and allow the performer (thereminist) to have more control of the sound produced.
Difference between IF and RF signal?
RF signal is coming from an antenna. So it contains electromagnetic waves. But when the signal is processed using electronics circuits, the range of frequency may not be sufficient. So that RF has to be convert to some other frequency acceptable by the circuit. And IF is the intermediate frequency used for tuning & other purpose.
What is stagger tuned amplifier?
Stagger Tuned Amplifiers are used to improve the overall frequency response of tuned Amplifiers. Stagger tuned Amplifiers are usually designed so that the overall response exhibits maximal flatness around the centre frequency.It needs a number of tuned circuit operating in union. The overall frequency response of a Stagger tuned amplifier is obtained by adding the induvidual response together. Since the resonant Frequencies of different tuned circuits are displaced or staggered, they are referred as STAGGER TUNED AMPLIFIER.The main advantage of stagger tuned amplifier is INCREASED BANDWIDTH. Its Drawback is Reduced Selectivity and critical tuning of many tank circuits. They are used in RF amplifier stage in Radio Receivers.
What is the advantages of using intermadiate frequency for satellite system?
There are three advantages to this type of frequency: 1) At very high frequencies (gigahertz), signal processing circuitry performs poorly. So a high frequency signal is converted to a lower intermediate frequency for processing. 2) In receivers that can be tuned to different stations, intermediate frequencies are used to convert the various different frequencies of the stations to a common frequency for processing. Without using intermediate frequencies, all the complicated filters and detectors in a radio or television would have to be tuned in unison each time the station was changed. 3) The primary advantage is that it improves frequency selectivity. In communication circuits, a very common task is to separate out or extract signals or components of a signal that are close together in frequency. This is called filtering. So a narrower bandwidth and more selectivity can be achieved by converting the signal to a lower intermediate frequency and performing the filtering at that frequency. Hope this helps!
What are the industrial applications of integrator and differentiator circuits using operational amplifier?
differentiator is used in t.v.
Does meter loading in ac circuits depend on frequency?
yes
Which kind of circuit is used in modern homes?
Electronic devices use all sorts of complicated electronic circuits - amplifier circuits for example, and switching circuits. The details, however, are a bit complicated for a short answer.
What is the concept of complex frequency in basic circuits?
Complex frequency is utilized in electric circuits in order to simplify the math, essentially. It is very similar to the use of phasors, except complex frequency can cover all types of inputs, not just sinusoids.
Difference between oscillator and amplifier?
The amplifier projects the audio signal into something we can comprehend. The oscillator creates a fixed or variable pitch, which is fed to the amplifier. Amplifiers are circuits which transfer an input signal into an output signal. Oscillators are autonomous circuits powered by a constant energy source. They produce a steady state signal e.g. a sinusoidal signal or a chaotic signal.
