1. Specification for information interchange on 3.81 mm (0.150 in) magnetic tape cassette at 4 cpmm (100 cpi), phase encoded at 63 ftpmm (1600 ftpi). (30th September 1981) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (28 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗