| 摘要 |
PURPOSE:To check a digital signal of a preset tuning voltage without causing any malfunction, by shifting the oscillation frequency of a signal generator so that an AFC voltage during intermediate frequency reception has the maximum or minimum value. CONSTITUTION:When a check switch 17 is turned on for checking, the switching circuit 19 in the signal generator 21 is changed over. Consequently, the signal generator 21 shifts the oscillation frequency so that the AFC voltage during intermediate frequency reception has the maximum or minimum value. This shifted oscillation frequency is supplied to an electronic tuner 10 to check the digital signal of the preset tuning voltage. Thus, the oscillation frequency of the signal generator is shifted during the checking to check the digital signal of the preset tuning voltage without causing any malfunction. |
