KR100274047B

• Main Author: KIM, YONG GYU
• Format: Patent
• Language: English
• Published: 15.12.2000
• Edition: 7
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

PURPOSE: A circuit for inputting a television signal is provided to remove an IF(Intermediate Frequency) signal by composing an induction trap filter on an output terminal of an antenna, to minimize mutual affection caused by tuning changes in bands, by matching an impedance of the antenna with resonant circuits of each band, and provided to be operated without being affected by other bands by giving divided bands from one output terminal, and to normally operate other parts even when malfunction occurs in one part. CONSTITUTION: A circuit for inputting a television signal comprises a first RF(Radio Frequency) resonant circuit(11), a second RF resonant circuit(12), a third RF resonant circuit(13), an induction trap filter(30), a first inductor(41), a second inductor(42), and a third inductor(43). The first RF resonant circuit processes a high band of a frequency band with 470 to 860MHz in a television frequency band. The second RF resonant circuit processes a mid band of a frequency band with 160 to 470MHz. The third RF resonant circuit processes a low band of a frequency band with 50 to 160MHz. The induction trap filter includes a fourth inductor for eliminating an IF(Intermediate Frequency) signal band in whole frequency Scopes received through the antenna, and for matching an impedance between the antenna and the each RF resonant circuit. The first inductor is connected between an output terminal of the inductor trap filter and an input terminal of the first RF resonant circuit in series. The second inductor is connected between the output terminal of the induction trap filter and an input terminal of the second RF resonant circuit in series. The third inductor is connected between the output terminal of the induction trap filter and an input terminal of the third RF resonant circuit in series.