What is the primary source of noise in analog electronics?
A Frequency
B Resistance
C Power supply
D Temperature
Thermal noise, or Johnson-Nyquist noise, is caused by the random motion of electrons in a conductor due to temperature. It is the primary source of noise in most analog electronic circuits, especially at higher temperatures.
What is the main consequence of distortion in an amplifier?
A Signal attenuation
B Harmonic generation
C Increased bandwidth
D Phase shift
Distortion in an amplifier primarily causes the generation of harmonics. These harmonics are unwanted frequency components that modify the original signal, resulting in a distorted output that differs from the input signal.
What type of distortion occurs when an amplifier’s output signal is clipped?
A Harmonic distortion
B Frequency distortion
C Amplitude distortion
D Intermodulation distortion
When an amplifier’s output signal is clipped due to excessive input voltage or saturation, amplitude distortion occurs. This results in a loss of signal integrity, particularly in terms of the signal’s peak levels.
Which of the following filters attenuates frequencies above a certain cutoff point?
A Low-pass filter
B Notch filter
C High-pass filter
D Band-pass filter
A low-pass filter allows signals with frequencies below a specific cutoff frequency to pass through while attenuating higher frequencies. It is commonly used to remove high-frequency noise from signals.
What is the effect of intermodulation distortion in an amplifier?
A Increased bandwidth
B Signal mixing at different frequencies
C Higher signal gain
D Decreased signal power
Intermodulation distortion occurs when multiple input signals mix and create additional signals at different frequencies. These unwanted frequencies can overlap with the original signal, causing interference and distortion.
What is the primary function of a band-pass filter?
A Amplify certain frequencies
B Reject low frequencies
C Allow specific frequency range
D Reject high frequencies
A band-pass filter allows signals within a specific frequency range to pass through while attenuating frequencies outside of this range. It is commonly used in applications like radio tuning and signal processing.
What is typically used to reduce noise in high-gain amplifiers?
A Feedback circuit
B Low pass filter
C High pass filter
D Shielding
Shielding is used to reduce noise in high-gain amplifiers by preventing electromagnetic interference (EMI) from external sources. It is essential in maintaining signal integrity, particularly in sensitive applications like audio or RF systems.
What does a notch filter do?
A Increases signal strength
B Blocks a narrow band of frequencies
C Reduces noise
D Passes high frequencies
A notch filter is designed to attenuate a very narrow band of frequencies while allowing others to pass. It is commonly used to remove specific unwanted frequencies, such as the hum of power line interference.
Which type of distortion occurs due to nonlinearities in a system?
A Temporal distortion
B Amplitude distortion
C Harmonic distortion
D Frequency distortion
Harmonic distortion occurs when nonlinearities in the system cause the generation of harmonics, or multiples of the original signal frequency. This alters the waveform, creating unwanted frequency components in the output.
In analog circuits, what is the primary cause of phase distortion?
A Temperature changes
B Frequency response limitations
C Nonlinear components
D Improper filtering
Phase distortion occurs when different frequency components of a signal experience different time delays. This is often caused by the limitations of an amplifier’s frequency response, which can affect the phase of the output signal.
What is the purpose of a low noise amplifier?
A Amplify power
B Minimize noise
C Increase bandwidth
D Reduce distortion
A low noise amplifier (LNA) is designed to amplify weak signals while introducing minimal additional noise. It is crucial in applications like radio receivers and medical instrumentation, where preserving signal integrity is important.
How does a high pass filter affect the frequency response of a signal?
A Rejects all frequencies
B Reverses signal polarity
C Passes high frequencies
D Passes low frequencies
A high pass filter allows high frequency signals to pass while attenuating lower frequencies. It is commonly used in applications where high frequency components of a signal are desired, such as in communication systems.
What is the characteristic of a signal that experiences frequency distortion?
A Incorrect frequency distribution
B Phase shift
C Incorrect amplitude
D Amplified noise
Frequency distortion occurs when different frequencies in a signal are amplified or attenuated disproportionately. This causes the frequency spectrum of the signal to be altered, leading to a distorted output.
Which type of distortion is most commonly associated with overdriving an amplifier?
A Amplitude distortion
B Intermodulation distortion
C Phase distortion
D Harmonic distortion
When an amplifier is overdriven, the output signal may become clipped, leading to harmonic distortion. This results in additional frequency components that are not present in the original input signal, distorting the waveform.
What is the typical use of a comb filter in signal processing?
A Create periodic attenuation
B Boost signal strength
C Eliminate noise
D Amplify low frequencies
A comb filter is used to create periodic attenuation or nulls at regular intervals in the frequency spectrum. It is often used in audio applications to create specific effects or to remove periodic interference.