IEC 60774-2:1999 pdf download – Helical-scan video tape cassette system using12,65 mm (0,5 in) magnetic tape on type VHs-Part 2: FMaudio recording.
This part of IEC 60774 is applicable to frequency modulation (FMI audio recording fully compatib4e with the VHS system defined in IEC 60774-I.
The object of this standard is to define the electrical and mechanical characteristics of FM audio recording which will provide f or the interchangeability of recorded cassettes. The requirements given relate to 525 line-60 field and 625 line-SO field systems.
2 Normative references
The lollowing normative documents contain provisions which, through reference in this text. constitute provisions of this part of IEC 60774. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of lEG 60774 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards
IEC 60774-1:1994, Helical-scan video tape cassette system using 2,65 mm (0,5 in) magnetic tape on type VHS — Part 1: VHS and compact VHS video cassette system
3 RecordIng method
The method of recording audio signals by frequency modulation Is specified.
The audio signal is recorded in the deep layer of the magnetic tape in the video track area prior to the video recording, with additional audio heads mounted on the common video rotating drum. The video signal is recorded on the surface layer according to lEG 60774-1 (depthmultiplex recording system).
The audio and video heads have different inclined azimuth gap angles in order to prevent mutual influences between audio and video signals.
4 Mechanical configuration
4.1 FU audio track pattern
The FM audio tracks are located in the centre of the video tracks as shown in figure 1. The dimensions shall be in accordance with table 1.
