LabGuy's World: Half Inch EIAJ-1 Format         Before 1969, very few video tape recorders, outside of the broadcast world, could interchange tapes. The situation was actually so grim, that in many cases, VTR's couldn't even exchange tapes with other models made by the same manufacturer! Then at the end of the 1960's, the Electronics Industry Association of Japan got the VTR manufacturers together and hammered out a standard for half inch open reel VTR's. Dozens of machines were made in this format, for almost a decade, before being displaced suddenly by half a dozen cassette formats! One of the cassette formats was even EIAJ compatible!   PARAMETER: METRIC SPECIFICATION: ENGLISH SPECIFICATION: Scanning Speed 11 . 1 m / s 437 in / s Drum Circumference 363 . 58 mm 14 . 32 in Drum Dieameter 115 . 82 mm 4 . 56 in Track Lengh (Approximate) 185 . 3 mm 7 . 29 in Track Angle (Tape Moving) 3 deg, 7 min, 43 sec 3 deg, 7 min, 43 sec Track Angle (Tape Stationary) 3 deg, 11 min 3 deg, 11 min Track Width (Minimum) 0 . 1 mm 0 . 003937 in Guard Band Width (Minimum) 0 . 04 mm 0 . 001575 in * Track Pitch 0 . 173 mm 0 . 0068 in Linear Tape Speed 190 . 5 mm / s 7.5 in / s         * Track pitch means the distance between the reference edges of the video track. It is an accurate measurement due to the mechanical construction of the tape guides and the scanning head. The width of the video track can vary due to head construction and wear, which will also vary the guard band width. Hence the minimum specified track and guard band widths do not total the track pitch. [HOME]......[EXTINCT DOCUMENTATION]......[EXTINCT FORMATS] Last updated: January 11, 2005