Abstract: The invention is comprised of two inductors wound in series but in opposite directions around a ferrite core, a resistor being connected in parallel with one inductor, and a wire being looped through a ferrite bead and being wound around the other inductor. The invention allows a 60 Hz power signal to pass without excessively interfering with radio frequency signals in excess of 900 MHz and preferably on the order of 1 GHz. The invention is particularly useful in cable television systems, where a power signal and an RF signal are sinultaneously transmitted.

Abstract: An electrical signal filter in which circuit provided with filter circuits are inserted into a cylinder-shaped shield case, has a first cavity portion having an inner case. The side of one end of the inner case has the circuit boards inserted, and the side of the other end thereof is provided with one of an input side connector and an output side connector. The electrical signal filter also has a second cavity portion having a second shield case having an outer case. The side of one end of the second shield case is provided with one of an output side connector and an input side connector.

Abstract: An improved F-connector for use in CATV, MATV and general television applications where coaxial cables and/or other devices must be connected to other cables or devices, the connector having an improved flat port through which internal components are inserted into a connector housing and which is thereafter formed by insertion of a flat insert or end cap which is fitted into the end of the connector housing and abuts against an internal shoulder therein.