(ISo International Standard 7929 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MEXAYHAPOAHAA OPTAHM3AUMA HO CTAHAAPTM3AUWWORGANISATION INTERNATIONALE DE NORMALISATION Information processing - Magnetic disk for data storage devices - 83 000 flux transitions per track, 130 mm (5.12 in) outer diameter, 40 mm (1.57 in) inner diameter Traitement de I'information - Disque magnetique pour unites de stockage des donnees - 83 000 transitions de flux par piste, diametre exterieur130 mm(5,12 in), diametre interieur40mm (1,57 in) First edition - 1985-06-01 ISO 7929-1985 (E) UDC 681.327.63 Ref. No.1SO7929-1985(E) Descriptors : data processing, information interchange, data storage devices, magnetic disks, specifications, mechanical properties, physical properties,magnetic properties,dimensions,tests. Price basedon15pages Foreword national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through isO technical committees. Each member body interested in a subject for which a technical committee has been established has mental and non-governmental, in liaison with iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with ISO procedures requiring at least75%approvafbythememberbodiesvoting International Standard ISO 7929 was prepared by Technicai Commitee ISO/TC 97, Informationprocessingsystems. international Organization for Standardization, 1985 Printed in Switzerland Contents Page Scope and field of application . 2 Reference 3 Conformance 4 Generalrequirements. Dimensions 2 6 Physical characteristics 2 Testing of magnetic characteristics 4 Surfacetests 9 9 Track quality tests 10 Requirementsformagneticsurfaces 8 11 Defectsofthemagneticsurfaces Annexes A Air cleanliness class 100 12 Method for measuring friction between head and disk 13 C Measurement of the effective trackwidth 15 ii