Method of conversion and converter of frequency modulated signal into pulse frequency Modulated signal with suppression of carrier frequency components of the pulse frequency modulation

摘要

Analog video tape recording (VTR) and video cassette recording (VCR) systems/apparatuses with novel converter of a frequency modulated signal into the pulse-frequency-modulated (PFM) signal during readback are described. The novel converter provides effective filtering function in itself and suppresses all carrier harmonics of the PFM signal. This reduces combination noise at the input to the PFM filter-demodulator by 20-25 db. Therefore, filtering requirements to PFM demodulator are greatly reduced and it can be of very simple design. The novel converter provides significant improvement in performance and reduces cost of analog VTR/VCRs.