| 摘要 |
PURPOSE:To prevent the deterioration of an S/N due to the intrusion of a higher harmonic noise into a voice signal on an analog line by inserting an LPF respectively into the neighborhood of the MODEM side, and the neighborhood of the digital circuit side in a digital line. CONSTITUTION:LPF 11 and 12 inserted respectively into the neighborhood of a connecting part with a MODEM 2, and the neighborhood of the connecting part with the digital circuit, in a digital line 4, absorb the higher harmonic noise generated due to data or a clock signal in the MODEM 2 or the digital circuit. Therefore, the higher harmonic noise can be prevented from being transmitted through the LPF11 and 12 to the line 4, and easily intruding into the voice signal on an analog line 6. Thus, the intrusion of the higher harmonic noise on the line 4 arranged so as to be relatively long can be prevented, so that the deterioration of the S/N due to the intrusion of the higher harmonic noise into the voice signal on the line 6 can be prevented. Also, it is desired that the MODEM 2 is the MSK MODEM, and the digital circuit is a computer device 5 including a CPU. |
