that is where the end stage does not consume current when there is no signal to amplify. Opposite of a class A where the current is constant with any signal level (except saturation...)
Operation Cobra happened on 1944-07-31.
Class A is the most serious and has more severe penalties.
The penalties and even the crimes and their definitions vary from state to state. Not all states have a Class C felony.
Like many electronic devices, tubes (aka valves) are closer to linear in certain operating ranges--meaning the output is a scaled version of the input when operating in the linear region. However, these linear regions are not typically at zero volts. So a DC bias is added to the AC input signal, shifting the signal into the linear region of the device. The DC bias can be removed from the output, leaving the amplified signal. Essentially the bias shifts the "zero" point for the signal to match the amplifier characteristics. Choosing bias is an important consideration in amplifier design. Amplifiers are designated by a "class" according to their bias--class A, class B, class AB, class C (there are other classes but they aren't used with tubes). Because the bias signal is the zero signal input, the bias determines how much power the tube uses when idle. For example, a class A amplifier is biased to the middle of the tube operating range so it uses about 50% power when idle, which is wasteful and makes a lot of heat.
transformer coupling
A Class C amplifier typically uses less than fifty percent of the input signal in other amplifiers. It also has two modes of operation, which are tuned and untuned. The tuned circuit emits at a certain fixed frequency, while the untuned can vary.
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.
Class C amplifier.. A class D amplifier is more efficient than class B, and is more efficient than class C as well.
Efficiency of class C amplifier is approximately 100%.
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.
class C
btwn 80-90%
class C because Class C also provides better signal,rejects unwanted signal.class c
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]
based on i/p:a) small signal amplifier b) large signal amplifierbased on o/p:a) voltage amplifier b) power amplifier c) current ampbased on bandwidth:a)untuned amp(wideband) b)tuned amp(narrowband)based on biasing condition:a)class A amp b) class B amp ......e)class D amp f) class s ampbased on no. of stages:a)multistage amp b) single stage amp
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.
Class C because of its high power gain.