1:Negative clipping of an output signal occurs when the

A. output impedance is too high.
B. input impedance is too high.
C. input amplitude is too high.
D. power supply voltage is too high.

2: Which of the following is essential for the operation of an oscillator?

A. Positive
feedback

B. Degenerative feedback

C. A unity gain amplifier

D. An LC circuit

number 1 is d and number 2 is a

1. To determine the answer to this question, you need to understand what negative clipping refers to in the context of an output signal. Negative clipping occurs when the amplitude of the output signal is limited or cut off below a certain threshold.

To determine the cause of negative clipping, you can eliminate the options one by one:

A. Output impedance being too high does not directly cause negative clipping. Output impedance refers to the impedance of the output stage and affects the loading of the circuit receiving the signal, but it does not directly determine the amplitude of the output signal.

B. Input impedance being too high also does not directly cause negative clipping. Input impedance refers to the impedance of the circuit receiving the input signal and affects the interaction between the source and the load, but it does not determine the amplitude of the output signal.

D. Power supply voltage being too high does not directly cause negative clipping. While high voltage could potentially result in distortion, it does not specifically produce negative clipping.

C. Therefore, the correct answer is C. If the input amplitude is too high, it can cause the output signal to exceed the maximum allowed amplitude and result in negative clipping.

2. To determine the essential requirement for the operation of an oscillator, you need to understand what an oscillator does and how it works. An oscillator is a device that generates a periodic and continuous signal without the need for an external input.

To determine the essential requirement, you can eliminate the options one by one:

B. Degenerative feedback refers to feedback that reduces the overall gain of the system. While feedback is commonly used in oscillators, degenerative feedback specifically reduces the gain and is not essential for the operation of an oscillator.

C. A unity gain amplifier refers to an amplifier with a gain of 1. While an amplifier may be used in an oscillator circuit, a unity gain amplifier is not a requirement for oscillator operation.

D. An LC circuit refers to a circuit that includes inductors (L) and capacitors (C). LC circuits are commonly used in oscillator circuits, and they are indeed essential for the operation of an oscillator. The combination of inductance and capacitance in an LC circuit allows for energy storage and periodic energy exchange, resulting in the generation of a continuous oscillating signal.

A. Therefore, the correct answer is A. Positive feedback is essential for the operation of an oscillator. Positive feedback occurs when a portion of the output signal is fed back to the input with the same phase or polarity. This positive feedback process reinforces the signal and sustains the oscillations in an oscillator circuit.