What Is a Frequency Meter?
A frequency meter is an instrument that measures signal frequency.
It is an electronic device or component that outputs frequency as a number, also called a frequency counter. It measures the number of periodic pulses of an electrical signal and outputs the frequency.
A frequency meter is used in many applications related to high-frequency radio technology to measure frequency signals with high accuracy. They provide accurate and precise measurements and allow detailed analysis of signal waveforms and frequency characteristics. The frequency meter is widely used in various areas of electrical testing to measure the frequency of repetitive signals.
Uses of Frequency Meters
Frequency meters are widely used in the fields of electrical engineering and communication engineering.
1. Equipment Reliability Evaluation
A frequency meter is widely used to evaluate the reliability of electronic equipment. Examples include noise generated in power circuits and evaluation of the operation of frequency conversion circuits.
2. Evaluation of Frequency Characteristics
Frequency meters are also used to evaluate frequency characteristics. For example, frequency response can be evaluated in acoustic equipment, such as amplifiers and speakers. They are also used to evaluate the characteristics of frequency filters.
3. Telecommunications Engineering
Frequency meters are also important measurement instruments in communications engineering. For example, they are used to adjust the frequency of transmitters and to evaluate the frequency of receivers. They are also used for fault analysis in wireless communications.
4. Power Measurement
A frequency meter is also used for power measurements. For example, they are used to evaluate the frequency of generators and transformers. They are also used to evaluate the efficiency of AC power in frequency converters.
5. System Design
A frequency meter is also used in system design. For example, they are used to evaluate the frequency response of an entire system or to design a frequency conversion circuit.
6. Acoustic Measurement
A frequency meter is used as a monitor to check the reflection and absorption of sound in an acoustic space, to create a uniform sound field, and to check the strength and frequency of vibrations emitted from equipment.
For example, a complex acoustic space is created in a car interior by sound reflection from the windshield and rear glass, sound absorption from the seats and floor, and engine noise. To create a comfortable sound, the frequency and signal strength distribution are checked with a frequency meter, and the highs and lows are strengthened or weakened with an equalizer to create a comfortable acoustic space.
Principle of Frequency Meters
A frequency meter is often used in combination with other measuring instruments, such as oscilloscopes. Frequency meter types include desktop, portable, high frequency, low frequency, RF (radio frequency), and microwave.
A frequency meter consists of a waveform shaping section, a reference time pulse generator, a gate section, and a display section. The input signal is shaped into a pulse train in the waveform shaping section, and a pulse with a precise time width of 0.1 or 1 second is generated in the reference time pulse generator.
The gate section switches the input signal shaped into a pulse train with pulses having this time width. The number of pulses obtained here is processed and output to the display section. For example, if the time width is 1 second and the number of input pulse trains is 10, the frequency is 10 Hz.
Care must be taken when measuring, because if noise is included, the pulse waveform may become unstable and the wrong frequency may be measured.
Other Information on Frequency Meters
1. Advantages of Frequency Meters
The advantage of a frequency meter is that it can measure not only frequency but also period, duty, etc. A frequency meter is a measuring instrument to check the performance of electronic circuits by digitally displaying the frequency.
They can be used as monitors to adjust the oscillation frequency to a predetermined value or to check the oscillation stability (frequency jitter). The principle is utilized in vibration and acoustic measurements. In this application, the input signal is Fourier transformed and displayed graphically as a spectrum.
Other applications include waveform observation and signal processing in the electronics field, ultrasonic measurement in the medical field, electromagnetic wave measurement, environmental surveys, and many others.
2. Application of Frequency Meters
A frequency meter comes with an application that not only quantifies the frequency of the input signal but also graphs it. While it is not possible to check for wobble or noise components using only numbers, FFT operations can be used to isolate the frequency components and graph their respective intensities.
Applications are provided to express signal quality in an easy-to-understand visual manner, such as displaying the strength of side lobes that appear next to the main signal, averaging the input signal to remove abrupt noise for accurate measurement, and expressing the wobble of the signal in terms of color shade.