U.S. Philips Corporation

Paul Friedel

Yannick Deville

Pierre Chanteau

A filter for treating a plurality of channels in a television signal cable distribution system comprises a plurality of paralel bandpass filters having a frequency which is individually controlled by frequency control voltages. A master filter provided with a filtering cell of a type identical to that used in a bandpass filter corresponds to each bandpass filter. For adjusting the central frequency of a master filter, a frequency is applied thereto by a frequency synthesizer and the cell is aligned with this frequency by acting on its frequency control voltage. This voltage is simultaneously applied to a bandpass filter for controlling the frequency, which is thus aligned with the frequency of the synthesizer simultaneously with that of the corresponding master filter. Each couple consisting of a bandpass filter and a corresponding master filter is realized by means of integration on the same semiconductor substrate (IC).

Growing community of inventors

Louviers, France

Paul Friedel