| 摘要 |
PURPOSE:To attain simply and efficiently the adjustment, by displaying an AFC voltage together with a limit voltage. CONSTITUTION:The AFC voltage is extracted from a terminal 7 of a television receiver 1, a switch 6 is opened at first and a reference volage V is measured with a voltmeter 9. Then, a signal having an intermediate frequency f0 is applied to an intermediate frequency amplifier circuit 3 from a reference oscillator 12 to discriminate the propriety of a discriminated output voltage from a frequency discriminating circuit 4 in this case. Then, a switch 15 is closed in advance to store the reference voltage V to a storage circuit 16 and a limit voltage V+ or -DELTAV is outputted from a limit setting circuit 17. Further, the switch 6 is closed and the discriminated output voltage is applied to voltage comparators 18, 19, 20 to discriminate the propriety. |
