| 摘要 |
PURPOSE:To obtain a power line carrier block filter free of a decrease in attenuation degree due to common-use impedance by mounting series resonating circuits and capacitors for parallel resonating circuits on the same printed board separately as two systems without connecting them in common on the board. CONSTITUTION:The block filter constituent parts of a single-phase three-wire circuit, namely, series resonating circuits 41 and 42 and capacitors C1, C2 and C3 for parallel resonating circuits are separated, and connected to power source side terminals of elements L1-L3 outside of a printed board 1 (L6-C6 and C7- R2; circuits for bypassing of out-of-phase carrier signals) by individual lead lines. Therefore, there is not any distributed inductance that the series resonating circuits 41 and 42 and parallel resonating circuits 31, 32 and 33 share, and high- efficiency attenuation characteristics are obtained without a decrease in attenuation degree, so that the leakage of a carrier frequency signal to an external power line is prevented securely. |
