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ND 312 Floppy Disk Drive, 1.2 Mbyte

INTRODUCTION

ND 312 Floppy Disk Drive reads and writes in single or double density on standard diskettes and on both sides of double-sided diskettes.

It is provided with:

  • A ceramic read/write head to provide media life exceeding 3.5 million passes/track and with head life exceeding 15,000 hours.
  • A Fasflex Head Positioning Actuator which positions the read/write heads to the desired track on the diskette. The Head Load Solenoid loads the read/write heads against the diskette and data may then be recorded on or read from the diskette.

FEATURES

  • Single or dual density diskettes.
  • Single- or dual-sided diskettes.
  • Media compatible with IBM 3740 and S/32 single-sided drives as well as IBM 4964, 3600 and S/34 series two-sided units.
  • Side by side mounting in standard 48 cm RETMA rack.
  • Up to 1.2 Mbyte storage per diskette.
  • Easy to maintain and service.
  • Fast 3ms track-to-track access time.
  • Programmable door lock and write protect for improved data security.
  • Same physical size as ND 310.
  • ND 310 I/O compatibility.

[Photo: ND 312 Floppy Disk Drive with visible internal components]

312-A1-6000-0282

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Product Description

The ND 312 Floppy Disk Drive consists of:

  1. Read/Write and Control Electronics.
  2. Drive Mechanism.
  3. Track Positioning Mechanism.
  4. Bi-Complaint Read/Write Head.

These components perform the following functions:

  • Interpret and generate control signals.
  • Move read/write head to the selected track.
  • Read and write data.

Performance Specifications

Capacity Single Density Double Density
Unformatted
Per Disk 800 KBytes 1,600 KBytes
Per Surface 400 KBytes 800 KBytes
Per Track 5.2 KBytes 10.4 KBytes
Formatted (IBM Extended)
Per Disk 606 KBytes 1,212 KBytes
Per Surface 303 KBytes 606 KBytes
Per Track 4.1 KBytes 8.2 KBytes
Transfer Rate 250 Kbits/sec. 500 Kbits/sec.
Latency (Avg.) 83 msec 83 msec
Access Time
Track to Track 3 msec 3 msec
Average (including settling) 91 msec 91 msec
Settling Time 15 msec 15 msec
Head Load Time 45 msec 45 msec

Functional Specifications

  • Rotational Speed: 360 rpm
  • Recording Density (inside track): 3,340 bpi
  • Flux Density: 6,816 fc
  • Track Density: 48 tpi
  • Cylinders: 77
  • Tracks: 154
  • Heads: 2

Data Capacity

Sectors/Track Bytes/Sector Kbytes/Diskette
IBM 3740 26 128 250
ND Single-Density 8 512 315
IBM SYS 34 26 256 998
ND Double-Density 8 1024 1261

Physical Specifications

  • Environmental Limits
    • Ambient Temperature: 4°C to 47°C
    • Relative Humidity: 20% to 80%
  • AC Power Requirements
    • 50/60 Hz ± 0.5 Hz
    • 200/230 VAC Installations: 170-253 V at 0.2 A typical, 0.25 A max
  • DC Voltage Requirements
    • +24 VDC ± 10% 0.85 A typical, 1.0 A max
    • +5 VDC ± 5% 0.8 A typical, 1.0 A TTY, 1.1 A max
  • Mechanical Dimensions (exclusive of front panel):
    • Height: 117 mm
    • Width: 241 mm
    • Depth: 362 mm
    • Weight: 5.91 kg
  • Heat Dissipation:
    • 60 watts typical
    • 72 watts max

Reliability Specifications

  • MTBF:
    • 5,000 POH under heavy usage.
    • 8,000 POH under typical usage.
  • PM:
    • Every 5,000 POH under heavy usage.
    • Every 15,000 POH under typical usage.
  • MTTR: 30 minutes.
  • Component Life: 15,000 POH.
  • Error Rates:
    • Soft Read Errors: 1 per 10¹⁰ bits read.
    • Hard Read Errors: 1 per 10¹² bits read.
    • Seek Errors: 1 per 10⁶ seeks.
    • Media Life: Passes per Track: 3.5 x 10⁶ Insertions: 30,000 + 
  +------------------------+
  |  ND Norsk Data         |
  |  Jerkaveien 20         |
  |  Boks 4 Linderberg gård|
  |  1360 Lø               |
  |  Tel: 02-390030        |
  |  Tlx: 18664 nd n       |
  +------------------------+

  +-----------------------+
  |    NP COMTEC          |
  |    Jerkaveien 20      |
  |    Boks 4 Linderberg  |
  |    oslo               |
  |    Tel: 02-390030     |
  |    Tlx: 18664 nd n    |
  +-----------------------+