| 摘要 |
PURPOSE:To make easy the adjustment work for electronic tuner, by transferring the frequency for adjustment written in advance to the preset area of RAM, at the initial condition setting after the application of power supply. CONSTITUTION:The value equivalent to the adjustment frequency for AM 5 points and FM 5 points is written in ROM 22. The control circuit 21 transfers the corresponding value to the adjustment frequency of ROM 22 to RAM 23 with the reset signal after application of power supply. AT the adjustment work, the signal transferred to RAM 23 is sequentially set to PLL 19, and the frequency is inputted to the tuning circuit of the high frequency amplifying circuit with the signal generator. This adjustment is made for the 5 points of the upper and lower limit frequencies and intermediate tracking frequencies by adjusting the tuning coils 121 and 131 and the semi-fixed capacitors 122 and 132. Further, the channel selection operation by the switch keyboard 24 is made the same as conventional methods. |
