Introduction; General Description - IBM 3274 51C Maintenance Information

E.1 INTRODUCTION
E.1.1 General Description
The IBM 31SD Diskette Drive is a direct-access, read/write,
data storage device. This drive uses the flexible magnetic
diskette for data entry, data exchange, and data storage.
The 31 SD Diskette Drive, shown in Figure E-1, can read
from and write to a diskette 1. The diskette drive reads
and writes in frequency modulation (FM) only. If a disk-
ette 2 or a diskette 2D is inserted into a 31SD Diskette
Drive, the drive will never come ready.
Figure E-1. IBM 31 SD Diskette Drive
Appendix E. IBM 31SD Diskette Drive Maintenance E-3