CATV Amplifiers are used to amplify TV signals before entering a receiver or a cable TV box. These types of amplifiers are designed to operate at frequencies specific to CATV to minimize amplification of unintended frequency bands and noise.  Cable TV amplifiers are usually installed in-line with coaxial cables.

The amplifiers are generally active and require an external power source to achieve the amount of gain required to drive the signal at the appropriate signal to noise ratio (SNR). Cable TV amplifiers are useful in households where there can be several 1 to 2 way splitters, which allow a common signal to be split and sent in two different directions. Generally these splits can reduce the signal power level by 3dB, which is 50 percent of the original power before the split. This amount of loss can be undesirable if done multiple times to meet the demands of the end application — which often involves connecting multiple cable boxes to the cable TV line. A CATV amplifier can be used to gain back the amount of loss incurred by the splitters, allowing the signal to be received at full signal strength.