Disk density
Overview

Disk density

Section Title: Overview
Table Section Text: None

Size	8-inch	5¼-inch	3½-inch

Density	SD	DD	SD	DD	QD	HD	DD	HD	ED	TD

Disk coating	Iron oxide	Cobalt	?	Iron oxide, Cobalt?	Cobalt	Barium ferrite	?

Coercivity [Oe]	290, 300	600, 660, 670	ca. 600	600?, 660, 670	700, 720	750?, 1060, 1200	?

Coating thickness [µ-inch]	?	?	?	100, 2.5 µm, 2.0-3.0 µm	?	55, 1.3 µm, 1.0-1.5 µm	?	65, 1.9 µm, 2.0-3.0 µm	55, 0.9 µm, 1.0-1.5 µm	?	?

Line code	FM	MFM, M²FM, FM/MFM or GCR	FM	MFM or GCR	MFM	MFM	MFM or GCR	MFM

Track width	0.330 mm	0.160 mm	?	0.115 mm	?

Track density [tpi]	48	96 or 100	96	67.5	135	406.5

Bit density [bpi]	5876, 5922	9646, 9870	8650	8717	17432, 17434	34868	36700

Recording direction	longitudinal / horizontal	perpendicular / vertical

Sentence(s)

High density (HD) utilizes a 96 tpi track density allowing 9646 bpi.

final_sentence: High density (HD) utilizes a 96 tpi track density allowing 9646 bpi.