| 摘要 |
PURPOSE:To correct a frequency automatically at every start of a transmitter and receiver by changing a local oscillated frequency in accordance with a shift width by only a CPU to facilitate adaptation. CONSTITUTION:When a device is started, the result of the work where the 1st and 2nd local oscillation frequency 81, 91 and a reception frequency is set to a center holding frequency of a BPF5 for SSB on a basis of a marker frequency 111 is stored in a CPU12 as fundamental set data of the first and the second local oscillation frequencies 81 and 91, and thereafter, frequency display is equalized that for SSB, and the frequency 91 is so corrected that it is shifted by 2,125Hz. In case of FSK transmission, the ASCII output of an FSK terminal 16 is inputted to the CPU to supply data 122 to a D/A converter 14 which controls the frequency 91 and the local oscillated frequency is switched to a BFO13B having an oscillated frequency which is higher than that of a BFO13A by 2,125 Hz to perform FSK modulation; and in case of FSK reception, a demodulation output 71 due to a demodulator 7A and the BFO13A is inputted to the CPU, and the frequency is counted and is decoded into a mark signal and a space signal, and they are converted to transmission codes and are transferred to a terminal 16. |
