What type of device is used to measure the frequency of an electrical signal?

• A. Oscilloscope
• B. Frequency counter
• C. Multimeter
• D. Ammeter

Answer: (B)

A frequency counter is specifically designed to measure the frequency of an electrical signal accurately. It works by counting the number of cycles of the signal that occur in a given time period. This makes it an essential tool in radio communications and electronic testing, as it allows operators and engineers to determine the precise frequency at which a signal is being transmitted or received.

In contrast, an oscilloscope is primarily used to visualize the waveform of electrical signals rather than to measure their frequency directly. While it can provide some frequency information by analyzing the signal over time, it does not yield an explicit frequency reading without additional calculations. A multimeter is a versatile instrument used for measuring voltage, current, and resistance, but it does not measure frequency. An ammeter specifically measures electric current, not frequency. Thus, the frequency counter is the tool intended for this particular function.