Understanding & Controlling Distortion in a Catv Network

INTRODUCTION While most of us have a general idea of distortion and know that it deteriorates the signal, it may be useful to re-state what is distortion. When a signal is processed through an electronic circuit, the output of the circuit often contains unwanted signals which were not part of the input. These unwanted output signal's frequency is usually related to the input signal's frequency. As a simple example, if a 100 MHz signal is fed into a CATV Amplifier, the output signal may contain unwanted signals at 200 MHz, 300 MHz, 400 MHz etc. These signals are referred to as distortion. It is important to note that only active electronic circuits generate distortion. Passive elements or circuits such as coaxial cables or even traps and filters do not generate any distortion.