Which device or circuit changes an alternating current into a varying direct current signal?

Which device or circuit changes an alternating current into a varying direct current signal?

• A. Amplifier
• B. Rectifier
• C. Transformer
• D. Capacitor

Answer: (B)

The device or circuit that changes an alternating current (AC) into a varying direct current (DC) signal is a rectifier. Rectifiers work by allowing current to flow in only one direction, effectively "clipping" the AC waveform to produce a DC signal that varies in amplitude depending on the input AC waveform. This process can be done using diodes, which are semiconductor devices that conduct current in one direction but not the other. Rectifiers can be used in power supply circuits to convert the AC voltage from power lines into a usable DC voltage for electronic devices, which typically require a steady DC input to function correctly. The output from a rectifier is not pure DC, but rather a varying DC voltage that can still be filtered to produce a smoother DC signal for final use. While amplifiers boost the power of a signal, transformers change voltage levels in AC circuits, and capacitors store and release electrical energy, they do not perform the conversion of AC to varying DC like rectifiers do. Therefore, the function of a rectifier is fundamental in electronic circuits that require the conversion from AC to a usable form of DC for various applications in ham radio and other electronic systems.

The device or circuit that changes an alternating current (AC) into a varying direct current (DC) signal is a rectifier. Rectifiers work by allowing current to flow in only one direction, effectively "clipping" the AC waveform to produce a DC signal that varies in amplitude depending on the input AC waveform. This process can be done using diodes, which are semiconductor devices that conduct current in one direction but not the other.

Rectifiers can be used in power supply circuits to convert the AC voltage from power lines into a usable DC voltage for electronic devices, which typically require a steady DC input to function correctly. The output from a rectifier is not pure DC, but rather a varying DC voltage that can still be filtered to produce a smoother DC signal for final use.

While amplifiers boost the power of a signal, transformers change voltage levels in AC circuits, and capacitors store and release electrical energy, they do not perform the conversion of AC to varying DC like rectifiers do. Therefore, the function of a rectifier is fundamental in electronic circuits that require the conversion from AC to a usable form of DC for various applications in ham radio and other electronic systems.