| 摘要 |
PURPOSE:To suppress the increment of sensitivity of even higher harmonic and to improve the modulating characteristics of a demodulator by dividing the potential difference between a standard level signal and an upper/lower level signal into right and left outputs by voltage dividing circuit and introducing these divided outputs in every a half period of a subcarrier. CONSTITUTION:The level of a composite signal Ct is converted at a fixed ratio PO by left and right standard level setting circuits 28 and 30. The level of the signal Ct is moreover set up by left and right upper/lower level setting circuits 27 and 29 at fixed ratios P1 and P2 so that the left and right phases are reversed, and the output differences between the circuits 28 and 27 and between 30 and 29 are divided by left and right resistance voltage dividing circuits 35 and 36. The divided outputs of the voltage dividing circuits 35 and 36 are scanned successively in both ways by analogue switches SW11-44 and SW11'-44' constituting right and left multiplexers in every a half period of a subcarrier to output left and right signals from output terminals OUTR and OUTL. |
