TUNER BLOCK FOR USE IN VIDEO SIGNAL RECEIVING APPARATUS HAVING MODULATOR, TUNER AND IF/DEMODULATOR CIRCUIT.

摘要

A TUNER BLOCK (150) IN WHICH A MODULATOR (51) AND AN IF/DEMODULATOR CIRCUIT (55) ARE INTEGRALLY FORMED.THE TUNER BLOCK (150) HAS A CASING FOR ACCOMMODATING A TUNER (53), THE IF/DEMODULATOR CIRCUIT (55) AND THE MODULATOR (51), AND SIXTEEN PINS CONSECUTIVELY DISPOSED AT AN OUTSIDE OF THE CASING. A NUMBER OF THE PINS IS REDUCED AS COMPARED WITH A CONVENTIONAL TUNER BLOCK (150) BY SUPPLYING AN ELECTRICAL POWER TO THE MODULATOR (51) AND THE TUNER (53) THROUGH A COMMON PIN, DISPENSING WITH PINS CARRYING UNNECESSARY SIGNALS AND PINS WHICH CARRY NO SIGNAL AND REARRANGING OTHER PINS. POTENTIAL FOR NOISE AND INTERFERENCE BETWEEN SIGNALS IS REDUCED BY MAXIMIZING DISPLACEMENTS OF CONNECTOR PINS WHICH CARRY SJGNALS WHICH ARE LIKELY TO INTERACT.A SWITCHING ARRANGEMENT PROVIDES FOR UTILIZING EITHER A CONVENTIONAL TUNER BLOCK (150) OR A TUNER BLOCK (150) ACCORDING TO THE PRESENT INVENTION ON A CIRCUIT BOARD.(FIGURE 6A)