| 摘要 |
PURPOSE:To obtain L and R signals, by performing the synchronizing detection by the output of a PM modulator and the output signal of an RF amplifier to obtain an L+R signal and by performing the phase detection of the output of an oscillator and a signal, which is obtained by eliminating AM components of the RF output by a limiter, to obtain an L-R signal and by processing both signals in a matrix circuit. CONSTITUTION:Stereo L and R signals are converted to a sum signal L+R and a difference signal L-R by a matrix circuit 1, and these signals pass through limiting amplifiers 2 and 3 and phase adjusters 4 and 5, respectively, and the difference signal is modulated in a PM modulator 6 by the output of an oscillator 7 which is FM-modulated by a stereo indication signal f0. The output of the PM modulator 6 is amplified together with the sum signal from a modulator 8 by an RF amplifier 9 and is transmitted from an antenna 12. A part of the output of the RF amplifier 9 is taken out by a directional coupler 10 and is detected together with the output of the PM modulator 6 by a synchronizing detector 23, and the sum signal is obtained by envelope detection. The output of the directional coupler 10 is applied to a phase detector 24 through a limiter 26 and is converted to the difference signal. These sum and difference signals are returned to L and R signals by a matrix circuit 27. |
