无绳话机简介天津市市内电话局于世河成，即：接收电路、控制电路和发送电路，如图３所示。其中：（１）接收电路主要是接收主机发出的无线射频信号，并经解调还原成有线的信令信号和话音信号。（２）发送电路是将话音信号和信令信号进行调频和放大，形成无线射频信号，并... Brief introduction of cordless phones Tianjin City Telephone Bureau in the world, namely: receiving circuit, control circuit and sending circuit, as shown in Figure 3. Among them: (1) The receiving circuit mainly receives the wireless radio frequency signal that the host computer sends out, and is demodulated and reduced and wired into the signal signal and the speech signal. (2) sending circuit is the voice signal and signaling signals for frequency modulation and amplification, the formation of radio frequency signals, and ...