| 摘要 |
PURPOSE:To enable to correct the frequency discriminator having variation in the characteristics, by converting the voltage signal adding the output of frequency discriminator and the voltage signal from the sample hold circuit at transmission into transmission frequency. CONSTITUTION:The transmission frequency f2 and the sub-local frequency f3 are mixed at the sub-mixer 14 to output the local frequency (f2+f3), and this local frequency and the transmission frequency are mixed at the main mixer 15 to form the intermediate frequency fIH. This intermediate frequency is converted into a voltage at the frequency discriminator 17 of which center frequency is selected at f3, and it is stored in the sample hold circuit 20 at transmission. The voltage signal from the frequency discriminator 17 and the sample hold circuit 20 at transmission is added at the addition circuit 22, this added voltage signal is fed to the high frequency voltage controlled oscillator 27 to output the transmission frequency f2. |
