| 摘要 |
PURPOSE:To attain FM modulation with excellent modulating linearity over a wide band without adjustment by adding an error detector to a frequency discriminator. CONSTITUTION:An input signal to be modulated is fed to an input terminal 21 and also to a non-inverting input terminal of the error detector 11. On the other hand, an inverting input terminal of the detector 11 is connected to an output terminal of the frequency discriminator 13, and the output terminal of the detector 11 is connected to an input terminal of an FM modulator main body. The oscillating frequency of the modulator main body 12 is increased when the input signal is increased positively. Then the output terminal 12 is connected to an FM modulation output terminal 22 and a part of the output terminls of the main body 12 is connected to an input terminal of the discriminator 13. The discriminator 13 has a characteristic generating an output voltage proportional to the frequency of the input FM signal. |
