Patent ID: 6078784
Filing Date: 2000-06-20
Classification: H03D,H04N

Abstract:
A multi-tap RF modulator which processes audio/video signals in a set top box (Sfor controlling TV broadcasting reception, the modulator comprising:an amplifier for amplifying a telecast RF signal input to an antenna input port, and outputting a first RF signal;a modulator section for outputting a second RF signal which modulates the audio/video signals;a mixer/splitter for mixing the first RF signal output from the amplifier and the second RF signal output from the modulation section, the mixed RF signals being distributed into more than one RF signal; andmore than one RF output tap for providing more than one RF signal to a main TV set and at least one sub-TV set;a capacitor connected between the output port of the mixer/splitter and the RF output tap connected to the sub-TV set; andfirst and second inductors connected in series at a node between the capacitor and the RF output tap connected to the sub-TV set, the first and second inductors' other port being connected to a power supply port of the STB which supplies direct-current voltage, the first and second inductors' node being connected to a digital control signal input port of the STB which controls broadcasting reception.