TV meter is commonly used in radio and television equipment in broadcasting. It is mainly used in terrestrial television, cable TV, satellite TV signal measurement and analysis. It is always an important job for its systematic evaluation and measurement to radio and television project, but the TV signal strength is the most basic measurement. Through the field strength measurements, we can have a preliminary understanding to the TV system equipment, the quality status of a network operation.
1. Basic concepts of signal level meter
Signal level meter (field strength meter) is an instrument measuring TV signal strength. Strength stands for electric field strength; it is the level of signal that antenna sensing at one point in space, to characterize the electric field strength at this point. TV signal strength measurement is actually measured by a standard antenna to receive induction territorial television signals, or directly connected to the output of the cable TV signal and read the signal strength with level meter.
Signal level meter makes dB as the unit, such as dBuV, dBmV, dBm.
2. Basic principle of signal level meter
Signal Level Meter is mainly used to test the TV field strength level, generally by the RF input and attenuation circuit, high-frequency tuning circuits, IF demodulation circuits, video processing circuits, spectrum processing circuit, synchronization and display circuit, sound and tone field circuit, power supply and battery charging circuit and other components. The signal level meter is equipped with a CPU, and directly displayed on the screen with a LCD, the operation is very convenient.
3. Function of signal level meter
In addition to the basic level measurement, signal level meter also has other functions, such as sound carrier measurement, carrier noise ratio measurement, TV picture display, audio monitoring, A/V audio video ratio measurement, spectrum measurement, TILT measurement, video output / input, external LNB power supply and so on. Signal Level Meter is generally equipped with a battery, power supply or car charger, easy to carry out for work. Some advanced signal level meter are with spectrum analysis, can make full span scan for the whole frequency range of television signals, or view the spectrum by selected range.
According to their functions, TV meter can be divided into TV signal level meter, TV spectrum signal level meter, CATV analyzer. An advanced TV meter can cover cable television and satellite TV bands, with the function of spectral analysis and color picture display, is capable of the measurement and analysis of both analog TV and digital TV signals.
by Radiasun meters, article source: http://www.radiasunmeters.com.