what does a suppression capacitor do
1 There are two major types of interference-suppression / AC line filter safety capacitors; namely, type X and type Y. The purpose of these capacitors is to reduce radio frequency interference and to ensure safety from shock and fire. In AC/DC (radios that do not use power transformers) radios where a line filter capacitor is connected between the hot and ground side of the power line, that capacitor is known as an across-the-line capacitor. 2  Across the line capacitors serve to keep RF noise disturbances from affecting the receiver.