21. Such changes in frequency relevant to social interaction are called frequency modulations ( FMs ). 22. The Japanese initially explored the idea of frequency modulation of a conventionally constructed composite signal. 23. Frequency modulation is widely used for FM radio broadcasting.24. A different control technique known as Pulse-frequency modulation can be used to minimize these losses. 25. FRS radios use narrow-band frequency modulation ( NBFM ) with a maximum deviation of 2.5 kilohertz. 26. The audio uses amplitude modulation rather than the frequency modulation in use on modern analogue systems. 27. The disks were Modified Frequency Modulation ( MFM ) coded in 512-byte sectors, and were soft-sectored. 28. Channels 1 3 must use " narrowband " frequency modulation ( 2.5 kHz deviation ). 29. Frequency modulation varies the frequency of the carrier.30. In addition a frequency modulation is applied to provide the recorder with an absolute time reference.
