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Why the name pushpull is given to pushpull amplifier?
Because first one side of the amplifier pushes on one half cycle then the other side of the amplifier pulls on the other half of the cycle.
What is A or C biasing?
The three standard forms of analog amplifier biasing are:class A - the amplifier is biased in the center of its linear operating range, this is the most linear but least efficient type of amplifier (because the transistors or tubes are always conducting, even when there is no signal to ampliify).class B - the amplifier is biased at the cutoff point, this is an efficient amplifier but is only linear if operated as a push-pull amplifier (because the transistors or tubes are in cutoff and not conducting when there is no signal and through one half of every cycle, a class B push-pull amplifier has two sections that operate on alternate halves of the cycle).class C - the amplifier is biased in hard cutoff so that only the peaks of the input signal are amplified, this is the most efficient amplifier (because the transistors or tubes may be in cutoff and not conducting for more the 85% of the time) but it is not capable of linear amplification. An amplifier biased as class C is only suitable for use in RF transmitter power stages, where a resonant LC tank circuit will be excited into oscillation by the output of the amplifier and complete the missing parts of the cycle.There are other forms of biasing (e.g. class AB) analog amplifiers that get some of the advantages of two of the standard forms. There are also forms of amplifiers having other nonstandard classes (e.g. class D) that are not analog amplifiers, but instead operate by amplifying pulses.
Can a single diode be connected as a full wave rectifier?
No. The diode conducts during only 1/2 of the cycle, leaving a big hole and no DC where the other half-cycle should be.
The class of amplification in which output current flows only for one half cycle is?
Recalling the class in Dr. Tuma's cave, that's Class B.(I never discarded any of my stone tablets.)
Is it possible to use class c amplifier in FM transmitter?
Technically possible, but not something you want to do. Once the carrier has been AM modulated, you need to handle it tenderly after that. Specifically, distortion has to be prevented, because distortion means new frequencies are introduced into the package, which makes the AM signal wider in occupied bandwidth ANDmakes AM sound terrible. Preventing distortion means the package can only be handled with 'linear' stages, and a Class-C stage is possibly the most non-linear kind of amplifier there is, since it's completely cut off for part of each RF cycle. By the way, this is the reason that AM is normally modulated in the RF power amplifier ... the last stage before the antenna. It would be a lot cheaper and easier to modulate at low level ... where much less audio power would be required ... and then RF-amplify the package for transmission, as is done in FM. But AM is so sensitive to distortion that it takes too much TLC to power-amplify it once it's been modulated. So amplifying (or frequency converting) are generally avoided after AM has been modulated.
Why efficiency of class c amplifier is high?
It conducts for less than one half cycle of the input.
What is class c tuned amplifier?
Class C tuned amplifier is a large signal tuned amplifier that amplifies high power signals of the radio frequency range. The amplifier is said to be Class C if the output cycle obtained is less than half a cycle of the full input cycle. This means the transistor remains active for less than half a cycle so that only that much part of the input waveform is reproduced at the output with amplification. For the remaining part, the transistor remains inactive.
What amplification is done by class c amplifier?
a class c amplifier conducts only for a small fraction of the period ( cycle ) of the input signal. hence its use is normally limited to circuits called oscillators where the high efficiency & power gain inherent of class C is utilised together with tuned circuits. As a matter of information, high fidelity amplifiers used for professional audio etc. use class A amplifier, where the amplifier works continoulsy over the full period of the input signal. Then there is class B type where the amplifier works for about 50% of the input signal period. This type of amplifier is used especially in High frequency circuits where the use of a Tuned circuit enables a full cycle to be generated even though the amplifier is working as class B A variation of clss B used especially in audio systems is with Two class B circuits each operating synchronously over a particular half of the signal, the two halves being combined to generate a whole signal cycle. Then there are inbetween variations called class AB etc. Modern digital technology has introduced Class D type amplifiers which are a different lot altogether.
Why the name pushpull is given to pushpull amplifier?
Because first one side of the amplifier pushes on one half cycle then the other side of the amplifier pulls on the other half of the cycle.
What is A or C biasing?
The three standard forms of analog amplifier biasing are:class A - the amplifier is biased in the center of its linear operating range, this is the most linear but least efficient type of amplifier (because the transistors or tubes are always conducting, even when there is no signal to ampliify).class B - the amplifier is biased at the cutoff point, this is an efficient amplifier but is only linear if operated as a push-pull amplifier (because the transistors or tubes are in cutoff and not conducting when there is no signal and through one half of every cycle, a class B push-pull amplifier has two sections that operate on alternate halves of the cycle).class C - the amplifier is biased in hard cutoff so that only the peaks of the input signal are amplified, this is the most efficient amplifier (because the transistors or tubes may be in cutoff and not conducting for more the 85% of the time) but it is not capable of linear amplification. An amplifier biased as class C is only suitable for use in RF transmitter power stages, where a resonant LC tank circuit will be excited into oscillation by the output of the amplifier and complete the missing parts of the cycle.There are other forms of biasing (e.g. class AB) analog amplifiers that get some of the advantages of two of the standard forms. There are also forms of amplifiers having other nonstandard classes (e.g. class D) that are not analog amplifiers, but instead operate by amplifying pulses.
Which class of amplifier have maximum distortion?
Class C since output cycle is less than 90 degrees for a full input. But it has highest power gain going upto 98%. And the exact term used for distortion is Total Harmonic Distortion since the distortion produced will be in multiples of the fundamental frequencies.
What is conduction angle?
Conduction angle refers to the portion of the cycle in which a device, such as a semiconductor switch or diode, conducts current. It is typically expressed as a percentage of the total cycle time. For example, a conduction angle of 60% means the device conducts for 60% of the cycle time. This parameter is important in power electronics applications to control the amount of power delivered to a load.
What is a class c amplifier?
A class A amplifier is an amplifier where the bias current in all amplifier stages, including the power amplifier, always exceeds the maximum output current. This leads to a very high energy consumption (and cooling might become a problem), but eliminates crossover distortions. Typical commercial amplifiers are what is called class A/B amplifiers, meaning, they would use a pretty high bias current to eliminate crossover distortions, but the bias current would still be less than the maximum output current to reduce the energy waste and cooling problems associated with pure class A amplifiers.
Can a single diode be connected as a full wave rectifier?
No. The diode conducts during only 1/2 of the cycle, leaving a big hole and no DC where the other half-cycle should be.
How does the circuit of a collector modulation work?
The output stage of the transmitter is a high power frequency class C amplifier. Class C amplifiers conduct for only a portion of the positive half cycle of their input signal. The collector current pulses cause the tuned circuit to oscillate or ring at the desired output frequency. The tuned circuit, therefore, reproduces the negative portion of the carrier signal. The modulator is a linear power amplifier that takes the low level modulating signal and amplifies it to a high power level. The modulating output signal is coupled through modulation transformer T1 to the class C amplifier. The secondary winding of the modulation transformer is connected in series with the collector supply voltage Vcc of the class C amplifier. Read more: [http://www.daenotes.com/electronics/communication-system/am-modulators#ixzz2R69fAPRC http://www.daenotes.com/electronics/communication-system/am-modulators#ixzz2R69fAPRC]
What is 90 percent -95 percent of the cell cycle?
The difference between 90% and 95% of the cell cycle is 5%. This means that 5% of the cell cycle is not overlapping between those two percentages.
How the capacitor removes the ripples from the rectified voltage?
During the AC cycle, the capacitor charges when the rectifier conducts, and maintains the voltage when the rectifier is not conducting.
