det var ju faktiskt rw på alla band också istället för gigg så talade man om timmar.
120 min kunde man få plats på ett band sedan kom 240 min.
Betamax is a consumer-level analog videocassette magnetic tape recording format developed by Sony, released in Japan on May 10, 1975. [1] The first Betamax introduced in America was the LV-1901 console, which included a 19" color monitor, and appeared in stores in early November, 1975. The cassettes contain .50 in (12.7 mm)-wide videotape in a design similar to the earlier, professional .75 in (19 mm) wide, U-matic format. The format is obsolete, having lost the videotape format war[2] to VHS. Betamax recorders ceased production in 2002, but the format's cassette tapes remain available until March 2016, when Sony will discontinue them.[3]
The VHS cassette is a 187 mm wide, 103 mm deep, 25 mm thick (73⁄8 × 41⁄16 × 1 inch) plastic shell held together with five Phillips head screws. The flip-up cover that protects the tape has a built-in latch with a push-in toggle on the right side (bottom view image). The VHS cassette also includes an anti-despooling mechanism consisting of several plastic parts between the plastic spools, near the front of the tape (white and black in the top view). The spool latches are released by a push-in lever within a 6.35 mm (¼ inch) hole accessed from the bottom of the cassette, 19 mm (¾ inch) inwards from the edge label.
There is a clear tape leader at both ends of the tape to provide an optical auto-stop for the VCR transport mechanism. A light source is inserted into the cassette through the circular hole in the center of the underside when loaded in the VCR, and two photodiodes are located to the left and right sides of where the tape exits the cassette. When the clear tape reaches one of these, enough light will pass through the tape to the photodiode to trigger the stop function; in more sophisticated machines it will start rewinding the cassette when the trailing end is detected. Early VCRs used an incandescent bulb as the light source, which regularly failed and caused the VCR to erroneously think that a cassette is loaded when empty, or would detect the blown bulb and stop functioning completely. Later designs use an infrared LED which had a much longer lifetime.
The recording media is a 12.7 mm (½ inch) wide, approximately 800 foot long Oxide-coated Mylar[25] magnetic tape that is wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder. The tape speed for "Standard Play" mode (see below) is 3.335 cm/s (1.313 ips) for NTSC, 2.339 cm/s (0.921 ips) for PAL—or just over 2.0 and 1.4 metres (6 ft 6.7 in and 4 ft 7.2 in) per minute respectively.
As VHS was designed to facilitate recording from various sources, including television broadcasts or other VCR units, content producers quickly found that home users were able to use the devices to copy videos from one tape to another. Despite the generation loss, this was regarded as a widespread problem, which the members of the Motion Picture Association of America (MPAA) claimed caused them great financial losses. In response, several companies developed technologies to protect copyrighted VHS tapes from casual duplication by home users.
därav Kopieringsavgift
