NEC FD1165 User manual

FDl165
Flexible Disk Drive
Maintenance
Manual
NEe
NEe Info,mation Systems,lnc.
819-000090-2001
10-82

LIABILITY DISCLAIMER
NEe
Information Systems, Inc. products are warranted in
accordance with the terms of the applicable NEC Information
Systems, Inc. product specification. Product performance
is affected by system configuration, software, the applica-
tion, customer data and operator control of the system among
other factors. While NECIS products are considered to be
compatible with most systems, the specific functional imple-
mentation by customers of the product may vary.
Therefore, the suitability of a product for a specific
application must be determined by the customer and is not
warranted by NECIS.
This manual is as complete and factual as possible at the
time of pr inting, however, the information in this manual
may have been updated since that time. NEC Information
Systems, Inc. reserves the right to change the functions,
features, or specifications of its products at any time,
without notice.
NEC Information Systems, Inc. has prepared this document for
use by NECIS employees and customers. The information con-
tained herein is the property of NECIS and shall not be re-
produced in whole or in part without prior written approval
from NECIS.
First Printing - October 1982
Copyright 1982©
NEe Information Systems, Inc.
5 Militia Drive
Lexington, MA 02173
Printed in U.S.A.

FEDERAL COMMUNICATIONS COMMISSION RADIO FREQUENCY
INTERFERENCE STATEMENT
Although disk drives as subsystem type components do not
require FCC rating, the following statement applies to the
Model FDl165.
This unit has been type tested ond found to comply with the
limits for a Class B computing device in accordance with the
specifications for Subpart J of Part 15 of FCC Rules, which
are designed to provide reasonable protection against such
interference in a residential installation.
Manufacturer's Instructions and User's Responsibilities
to Prevent Radio Freguency Interference
Manufacturer's Instructions
The user must observe the following precautions in install-
ing and operating this device:
1. Operate the equipment in strict accordance with the
manufacturer's instructions for the model.
2. Ensure that the unit :is plugged into a properly
grounded wall outlet and that the power cord sup-
plied with the unit is used and not modified.
3. Ensure that the unit is always operated with the
factory installed cover set on the unit.
4. Make no modification to the equipment which would
affect its meeting the specified limits of the
Rules.
5. Properly maintain the equipment in a satisfactory
state of repair.
ii i.

User's Responsibility
The user has the ultimate responsibility to correct problems
ar ising from harmful radio-frequency emissions from equip-
ment under his contiol. If this equipment does cause inter-
ference to radio or television reception, which can be
determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one of the
following measures. All of these responsibili ties and any
others not mentioned are exclusively at the expense of the
user.
1. Change in orientation of the receiving device
antenna.
2. Change in orientation of the equipment.
3. Change in location of equipment.
4. Change in equipment power source.
If these a ttempts are unsuccessful, install one or all of
the following devices:
1. Line isolation transformers
2. Line filters
3. Electro-magnetic shielding
If necessary, the user should consult the dealer, NEC or an
experienced radio/television technician for additional sug-
gestions. The user may find the following booklet prepared
by the Federal Communications Commission to be helpful~ "How
to Identify and Resolve Radio-TV Interference Problems."
This booklet is available from the u.s. Government Printing
Office, Washi'ngton, D.C. 20402, Stock No. 004-000-00345-5.
"Note: The operator of a computing device may be required
to stop operating his device upon finding that the device
is causing harmful interference and it is in the public
interest to stop opera tion until the interference problem
has been corrected."
iv

CONTENTS
CHAPTER 1 GENERAL INFORMATION
1.1
1.2
DESC.RI PTION •• •••••••••••••••••••••••••••••••••
CONSTRUCTION AND FEATURES •••• ~ ••••••••••••••••
1-1
1-2
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
1.2.8
1.2.9
1.2.10
1.2.11
1.2.12
1.2.13
1.2.14
1.2.15
1.2.16
1.2.17
1.2.18
Base Frame •••••••••••••••••••••••••••
Spindle Assembly •••••••••••••••••••••
Dc Direct Drive Spindle Motor ••••••••
Carriage Read/Write Assembly Heads •••
Stepping Motor •••••••••••••••••••••••
Head Load Cam Assembly •••••••••••••••
Pop-Up Feature •••••••••••••••••••••••
Index Sensor •••••••••••••••••••••••••
00 Track Sensor ••••••••••••••••••••••
Write Protect Sensor •••••••••••••••••
Media-In Sensor ••••••••••••••••••••••
Collet Assembly ••••••••••••••••••••••
Printed Circuit Board (PCB) ••••••••••
Variable Frequency Oscillator
,(Optional) .
Display Lamps ••••••••••••••••••••••••
Front Panel •••• " ••• · ••••••••••••••••••
Movable Door Handle ••••••••••••••••••
Door Lock Solenoid •••••••••••••••••••
1-2
1-2
1-3
1-3
1-3
1-3
1-4
1-4
1-4
1-4
1-4
1-4
1-4
1-4
1-5
1-5
1-5
1-5
1.3
SPECIFICATIONS ••••••••••••••••••••••••••••••••
1-5
CHAPTER 2INSTALLATION AND OPERATION
2.1
2.2
PRELIMINARY INSPECTION .
UNPACKING AND REPACKING •••••••••••••••••••••••
2-1
2-1
ENVIRONMENTAL REQUIREMENTS ••••••••••••••••••••
2.3
2.2.1
2.2.2
2.2.3
2.3.1
2.3.2
2.3.3
Unpacking Procedure ••••••••••••••••••
Repacking Procedure ••••••••••••••••••
Preinsta11ation Inspection •••••••••••
Operating Environment ••••••••••••••••
Space and Weight Data ••••••••••••••••
Mounting •••••••••••••••••••••••••••••
v
2-1
2-1
2-3
2-3
2-3
2-3
2-3

CONTENTS (cont'd)
2.4 POWER SUPPLy ••••••••••••••••••••••••••••••••••
Page
2-6
INTERFACE CONNECTION ••••••••••••••••••••••••••
TERMINATOR RESISTORS ••••••••••••••••••••••••••
OPTION SELECTION ••••••••••••••••••••••••••••••
DRIVE IDENTIFICATION (DX) SELECTION •••••••••••
2-9
2-12
2-6
2-6
2-7
2-8
2-12
2-12
2-12
2-12
2-13
2-13
2-13
Power Supply Specifications ••••••••••
Power Connec tor ••••••••••••••••••••••
Power Connector Pin Assignments ••••••
Head Load Jumper (HL) ••••••••••••••••
Radial Ready Jumper (RX) •••••••••••••
Side Select Jumper (SS) ••••••••••••••
Wr i te Protect Jumper (PR) ••••••••••••
File Unsafe Jumper (FR) ••••••••••••••
Door Lock Jumpers (DL, DR, DH) •••••••
2.4.1
2.4.2
2.4.3
2.8.1
2.8.2
2.8.3
2.8.4
2.8.5
2.8.6
2.5
2.6
2.7
2.8
OPERATING THE FDl165 ••••••••••••••••••••••••••
DIS PLAY LAMPS •••••••••••••••••••••••••••••••••
2.9
2.10
2.8.6.1
2.8.6.2
2.8.6.3
2.8.7
2.8.8
2.8.9
2.8.9.1
2.8.9.2
2.8.9.3
2.9.1
2.9.2
2.10.1
2.10.2
DR Jumper ••••••••••••••••••••••••••••
DL Jumper ••••••••••••••••••••••••••••
DH Jumper ••••••••••••••••••••••••••••
In Use Pins (US) •••••••••••••••••••••
Rea d Da taP ins ( RD) ••••••••••••••••••
Busy Lamp Jumpers (BU, BS) •••••••••••
Busy Lamp On During Head Load ••••••••
Busy Lamp On During Drive Select •••••
Busy Lamp On During In Use •••••••••••
Inserting a Flexible Disk ••••••••••••
Removing a Flexible Disk •••••••••••••
Ready Lamp •••••••••••••••••••••••••••
Busy Lamp ••••••••••••••••••••••••••••
2-13
2-13
2-13
2-14
2-14
2-14
2-14
2-15
2-15
2-15
2-15
2-16
2-16
2-16
2-17
vi

CHAPTER 3
CONTENTS (cont'd)
INTERFACE INFORMATION
3.1
BASIC OPE:RATIONAL DESCRIPTION •••
3-1
3.2
ELECTRICAL INTERFACE ••••• .....................
3-2
3.2.1
3.2.2
3.2.3
Signal Levels ••.•••••••••••••••••••••
Driver/Receiver Circuits •••••••••••••
Interface Lines ••••••••••••••••••••••
3-2
3-2
3-3
3.3 INPUT SIGNALS ••••••••••••••••••••••••••••.••••
3-3
3.3.1
3.3.2
3.3.3
3.3.4
3.3.5
3.3.6
3.3.7
3.3.8
3.3.9
3.3.10
Drive Select 1 Through 4(DSXl to 4).
Head Load (HDL) ••••••••••••••••••••••
Step (STP) •••••••••••••••••••••••••••
Direction Select (DIR) •••••••••••••••
Side Select (SSL) ••••••••••••••••••••
Write Gate (WGT) •••••••••••••••••••••
Write Data (WDT) •••••••••••••••••••••
Low Wr i te Current (LWC) ••••••••••••••
File Unsafe Reset (FUR) ••••••••••••••
In Use (USE) ••• It •••••••••••••••••••••
3-3
3-4
3-4
3-4
3-4
3-5
3-5
3-5
3-6
3-6
3.4
OUTPUT
SIGNALS .................
3-6
3.4.1
3.4.2
3.4.3
3.4.4
3.4.5
3.4.6
3.4.7
3.4.8
Index (IDX) .
Tr ack 00 (TKO) .
Dual-Sided (TSD) •••••••••••••••••••••
Ready (ROY) ••••. ~ •••••••••••••••••••••
File Unsafe (FUS) ••••••••••••••••••••
Read Data (ROT) .
Write Protect (PRT) ••••••••••••••••••
Dis k Chan ge (DCG) ••••••••••••••••••••
3-6
3-7
3-7
3-7
3-7
3-8
3-8
3-8
3.5
VFO INTERFACE SIGNALS •••••••••••••••••••••••••
3-9
3.5.1
3.5.2
3.5.3
3.5.4
Modified Frequency Modulation Mode
(MFM) ••••••••••••••••••••••••••••••
VFO Synchroni zation (SYC) ••••••••••••
Standardized Read Data (SRD) •••••••••
Wi ndow (WID) •••••••••••••••••••••••••
3-9
3-9
3-9
3-9
3.6
INTERFACE TIMING ••••••••••••••••••••••••
3-10
3.6.1
3.6.2
3.6.3
3.6.4
3.6.5
3.6.6
Power On Sequenc e ••••••••••••••••••••
Drive Select •••••••••••••••••••••••••
Step and Track 00 ••••••••••••••••••••
Access •••••••••••••••.•••••••••••••••
Wr i te .
Read .••••••••••••••••••••••••••••••••
vii
3-10
3-10
3-10
3-11
3-11
3-12

CONTENTS (cont'd)
CHAPTER 4 MAINTENANCE
4.1
4.2
4.3
4.4
PREVENTI VE MAINTENANCE ••••••••••••••••••••••••
MAINTENANCE TOOLS •••••••••••••••••••••••••••••
MAINTENANCE PARTS •••••••••••••••••••••••••••••
REMOVAL AND REPLACEMENT PROCEDURES ••••••••••••
4-1
4-1
4-1
4-2
4.4.1
4.4.2
4.4.3
4.4.4
4.4.5
4.4.6
4.4.7
4,,4.8
4.4.9
.4 .4.10
4.4.11
4.4.12
4.4.13
4.4.14
4.4.15
PCB Removal •••••••••••••••••••• " •••••
Collet Assembly Removal, Replacement,
and Adj ustmen t •••••••••••••• " ••••••••
Carriage Assembly Removal and
Replac ement ••••••••••••••••••••••••••
Head Load Cam Assembly and Head Load
C~m Removal and Replacement ••••••••••
Write Protect Sensor and Media-In
Sensor Removal and Replacement •••••••
Optical Tachometer Sensor Removal
and Replacement •.••••••••••••••••••••
Sensor Cable Assembly (LED Assembly
and Index Sensor Removal and
Replacement ••••••••••••••••••••••••••
Removing and Replacing the Carbon
Brushes ••••••••••••••••••••••••••••••
Armature Removal •••••••••••••••••••••
Spindle Assembly Removal •••••••••••••
Front Panel Removal •••••••••••• , ••••• "
Picker Rod Removal and Replacement •••
Pop-Up Assembly Removal and
Replacement ••••••••••••••••••••••••••
Guide Rail Removal •••••••••••••••••••
Checking the Operation of the Pop-Up
4-2
4-3
4-6
4-8
4-9
4-10
4-11
4-14
4-15
4-16
4-17
4-17
4-18
4-19
4.4.16
Feature.............................. 4-19
Door Lock Solenoid Removal and
Replacement.......................... 4-20
CHAPTER 5 ADJUSTMENTS
DIAGNOSTIC TESTS ••••••••••••••••••••••••••••••
5.1
5.1.1
5.1.2
5.1.3
Auto Tap Test ••••••••••••••••••••.•••
Auto Seek Test •••••••••••••••••••••••
Auto Seek and Auto Tap Test .•••••••••
5-1
5-2
5-2
5-2
5.2
5.3
HEAD UNLOAD DELAy •••••••••• """"""" II " " " " " • " • " ••
TEST PO INTS •••••••••••••••••••••••••••••••••••
viii
5-2
5-3

5.4
CONTENTS (cQnt'd)
ADJUSTMENTS AND CHECKS USING THE ALIGNMENT
FLEXIBLE DISK ••••••••••••••••••••••••••••••••• 5-3
O'l"HER ADJUSTMENTS •••••••••••••••• ~ ••••••••••••
TRIM POTS •••• .- ••••••••••• ~ ••••••••••••••••••••
5.5
5.6
5.4.1
5.4.2
5.4.3
5.5.1
5.5.2
5.5.3
5.5.4
Head Radial Alignment Check or
Ad j' ustmen t •••••••••••••••••••••••••••
Azimuth Check ••••••••••••••••••••••••
Index Alignment Check or Adjustment ••
LED Assembly/Index Assembly Check
and Adjustment •••••••••••••••••••••••
00 Track Sensor Check or Adjustment ••
Write Protect Sensor Check or
Ad j us tmen t •••••••••••••••••••••••••••
Head Load Check ••••••••••••••••••••••
5-4
5-6
5-7
5"'8
5-8
5-9
5-10
5 ..... 10
5-11
CHAPTER 6 ILLUSTRATED PARTS BREAKDOWN
CHAPTER 7 SCHEMATIC
ix

Figure
1-1
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12
2-13
2-14
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
ILLUSTRATIONS
Title
FDl165 Flexible Disk Drive ••••••••••••••••••
Unpack ing ••••••••••••••••••••••••••••.••••••
Model FDl165 Physical Dimensions ••••••••••••
Vertical Installation .••••••••••••••••••.•••
Horizontal Installation •••••••••••••••••••••
On-End Installation •••••••••••••••••••••••••
Air Flow Requirements for Natural Air
Cool ing ••••••••••••••••••• ' ••••••••••••••••••
Power Connector Location ••••••••••••••••••.•
Pin and Line Assignments for the Power
Connec tor •••••••••••••••••••••••••••••••••••
Contact Arrangement for Edge Connector ••••••
In terf ace Connector •••••••••••••••••••••••••
Terminator Resistors and Jumper Locations
on the PCB •••••••••••••••.•••••••••••••.••••
Parallel and Series Configurations ••••••••••
Closing the Door of the FDl165 ••••••••••••••
Unlocking the Door and Removing the
Fle'xible Disk •••••••••••••••••••••••••••••••
Dr i ver /R ec e i ver Ci r cui ts••••••••••••••••••••
Interface Lines •••••••••••••••••••.••••••••.
Step Signal Timing ••••••••••••••••••••••••••
WGT Timing ••••••••••••••••••••••••••••••••••
Write Data Signal Ximing ••••••••••••••••••••
Index Signal Timing ••••• ~ •••••••••••••••••.•
Read Data Signal Timing ••••••••••••••••.•.••
Disk Change Signal Timing •.•••••••.•••••••••
Read Data and Window Signal Timing ••••••••••
Step and Track 00 Timing ••••••••••••••••••••
Acce ss T imi ng •••••••••••••••••••••••••••••••
Write Timing ••••••••.••••••••••••••••••••.••
Read T imi ng ••••••••••••••.••••••••••••••••••
Removing the Collet Assembly ••••••••••••••••
Replacing the Collet Assembly •••••••••••••••
Head Unload Spring in Relation to Spring
Plate .
Position of the Spring Plate ••••••••••••••••
Carriage Assembly position on the Base Frame
Removing the Head Load Cam ••••••••••••••••••
Installing the Head Load Cam Assembly •••••••
Write Protect or Media-In Sensor
Page
1-2
2-2
2-4
2-4
2-4
2-5
2-5
2-7
2-7
2-8
2-8
2-10
2-11
2-15
2-16
3-2
3-3
3-4
3-5
3-6
3-6
3-8
3-9
3-10
3-10
3-11
3-11
3-12
4-3
4-4
4-5
4-5
4-7
4-8
4-9
Connections................................. 4-10
4-9 Installing the Write Protect or Media-In
Sensor...................................... 4-10
4-10
Removing the Replacing the Optical
Tachometer Sensor •••••••••••••••••••••••••••
x
4-11

Figure
4-11
4-12
4-13
4-14
4-15
4-16
4-17
4-18
4-19
4-20
5-1
5-2
5-3
5-4
5-5
5-6
5-7
5-8
6-1
6-2
Table
1-1
2-1
2-2
2-3
2-4
4-1
4-2
5-1
5-2
5-3
5-4
5-5
6-1
ILLUSTRATIONS (cont'd)
Title
Removing the Sensor Cable Assembly ••••••••••
Installing the Index Sensor •••••••••••••••••
Removing a Carbon Brush •••••••••••.•••••••••
Removing the Armature •••••••••••••••••••••••
Removing the Spindle Assembly •••••••••••••••
Removing the Front Panel ••••••••••••••••••••
Adjusting the Picker Rod ••••••••••••••••••••
Removing the Pop-Up Assembly and Guide Rail.
Removing the Door Lock Solenoid •••••••••••••
Adjusting the Door Lock Solenoid ••••••••••••
Location of Diagnostic Test Pins and Test
Po in ts .
Head Radial Alignment Waveform ••••••••••••••
Adjusting Head Radial Alignment •.••••••••••.
Azimuth Waveform •• ~ •••••••••••••••••••••••••
Index Alignment Waveform ••••••••••••••••••••
Waveforms at TP7 and TP10 •••••••••••••••••••
Track 00 Signal •••••••••••••••••••••••••••••
Head Load Waveform ••••••••••••••••••••••••••
FDl165 Flexible Disk Drive ••••••••••••••••••
G9NYF PCB Assembly ••••••••••••••••••••••••••
TABLES
Title
FDl165 Specifications •••••••••••••••••••••••
Power Supply Specifications ••••••••••.••••••
Power Connector Part Number ••••••••••••.••••
Data and Control Interface Contact
Ass ignmen ts •••••••••••••••••••••••••••••••••
Door Lock Jumper Combinations •••••••••••••••
Maintenance Tools ••••••••••••••••••••••.••••
Maintenance Parts ••••••.••••••••••••••••••••
Test Points and Signals •••••••••••••••••••••
Adj ust.ments •••••••••••••••••••••••••••••••••
Head Radial Alignment Oscilloscope Settings.
Head Azimuth Oscilloscope Settings ••••••••••
Index Alignment Oscilloscope Settings •••..••
List of Illustrations •••••••••••••••••••••••
xi
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6-3

LIST OF ABBREVIATIONS
A Ampere
DIR Direction Select
DCG Disk Change
DLH Door Lock Hold
DSX Drive Select
FDD Flexible Disk Drive
FM Frequency Modulation
FUR File Unsafe Reset
FUS File Unsafe
HLD Head Load
IC Integrated Circuit
IDX Index
I/O Input/Output
k 1000
kg Kilogram
LED Light Emitting Diode
LSI Large-Scale Integration
LWC Low Write Current
rnA Milliampere
MB Megabyte
MFM Modified Frequency Modulation
ms Millisecond
mV Millivolt
PCB Printed Circuit Board
POH Power-On-Hours
pp Peak-To-Peak
PRT Write Protect
ROT Read Data
ROY Ready
rpm revolutions per minute
SRO Standardized Read Data
SSL Side Select
STP Step
SYC Synchronization
TKO Track 00
TSD Two-Sided Disk
TTL Transistor Transistor Logic
USE In Use
Vdc Volts direct current
VFO Variable Frequency Oscillator
WDT Write Data
WGT Write Gate
WID Window
~s Microsecond

CHAPTER 1
GENERAL INFORMATION
This chapter gives an overall description of the Model
FDl165 8-Inch Flexible Disk Drive, describes the features
and parts of the disk drive in detail, and lists the speci-
fications.
1.1 DESCRIPTION
The Model FDl165 Flexible Disk Drive is a compact magnetic
disk storage device that uses single- or dual-sided, single-
or double-density flexible disks. The storage capacity of
the disk drive depends on the type and format of the disk-
ette that is used. wi th a dual-sided flexible disk and a
double-density format, the maximum-storage capacity is 1.6
million bytes (MB).
The most apparent features of the Model FDl165 are its small
size and light weight. The disk drive measures 8.55 inches
(2l7.2 rom) high, by 2.28 inches (58.0 rom) wide by 13.20
inches (335.0 rom) deep and weighs only 7.7 pounds (3.5 kg).
The disk drive has all the features and performance of
larger, conventional units, and is media-compatible and
interface-compatible with ~hem. Because the Model FDl165
measures one-half the height of 'conventional disk drives,
two disk dr i ves can be mounted in the same space as one
conventional drive.
The Model FDl165 is operated by an external controller (NEC
~PD765 is recommended) through a Transistor Transistor Logic
(TTL) interface. The disk drive requires an external power
supply that must supply and control two vol tages, +5 Vdc
(for the TTL) and +24 Vdc (for the dc direct drive spindle
motor) (see Section 1.2.3). The disk drive features a
microprocessor-controlled head loading mechanism that mini-
mizes head and media wear. The head position mechanism
(stepping motor) is also microprocessor-controlled to ensure
extremely accurate head positioning.
1-1

1.2 CONSTRUCTION AND FEATURES
This section describes the construction of the Model FDl165
and explains the features of the various assemblies. See
Figure 1-1 to identify the assemblies that are described in
this section.
HEAD LOAD
SOLENOID
Figure 1-1 FDl165 Flexible Disk Drive
1.2.1 Base Frame
The base frame is the metal form that supports the sub-
assemblies of the disk drive.
1.2
b2
Spindle Assembly
The spindle assembly supports the flexible disk in the disk
drive and rotates the flexible disk at 360 revolutions per
minu te (rpm).
1-2

1.2.3 Dc Direct Dtive Spindle Motor
The dc direct drive motor (not shown) rotates the spindle
assembly. This dc motor eliminates the problems that are
associated with conventional ac motor drives.
• The motor does not use drive pulleys or belts, elim-
inating the problems associated with these parts.
• The motor consumes less power than conventional ac
motor s. Low-power, inexpensi ve power suppli es can
be used.
• The motor uses direct current, so that there are no
concerns about voltages and frequencies.
• The motor generates less heat than conventional
un its.
The spindle motor has an up-to-speed time of 700 ms.
1.2.4 Carr! age Read/Wr i te Assembly Heads
The read/write heads touch each side of the flexible disk,
allowing data to be written to the flexible disk and to be
read from it. The read/write heads are part of a precision
carriage assembly that shifts the heads from track to track.
During the loading of a flexible disk, the read/write heads
are held away from the surface of the flexible disk.
1.2.5 Stepping Motor
The stepping motor, under microprocessor control, positions
the carriage assembly with a tensioned steel belt. This
arrangement provides fast and accura te data access. For
each pulse the stepping motor receives, the stepping motor
shaft rotates 1.8 degrees. This action, in turn, moves the
carriage 1/2 track on the flexible disk.
1.2.6 Head Load Cam Assembly
The head load cam assembly (rotary solenoid) lowers the
heads onto the flexible disk with a force that is controlled
by a microprocessor. This action prevents damage to the
flexible disk and reduces wear of the read/write heads.
1-3

1.2.7 Pop-Up Feature
For easy removal of the flexible disk from the disk drive,
the pop-up feature ejects the flexible disk from the disk
drive when the door is opened. After ejection, the edge of
the flexible disk protrudes approximately 1/2 inch (13 mm)
from the disk drive.
1.2.8 Index Sensor
The index sensor is a combination LED and phototransistor
that senses the index position of the flexible disk. The
Model FDl165 has a dual index sensor to detect both single-
sided and dual-sided flexible disks.
1.2.9 00 Track Sensor
The 00 Track sensor detects when the read/write head is at
the 00 track (track 0, side 0).
1.2.10 Write Protect Sensor
The write protect sensor detects the presence or absence of
a write protect notch on the flexible disk. If there is a
notch, the write function is disabled. If no notch exists,
the write function operation is enabled.
1.2~11 Media-In Sensor
The media-in sensor detects the presence of a flexible disk
in the disk drive.
1.2
0
12 Collet Assembly
The collet assembly holds the flexible disk in position on
the spindle when the door is closed.
1.2.13 Printed Circuit Board (PCB)
The PCB (not shown) supports the electronic drive and logic
circuits of the disk drive.
1.2.14 Variable Frequency Oscillator (Optional)
The optional Variable Frequency Oscillator (VFO) PCB makes
the interface signals to the controller more stable, in-
creasing the overall reliability of the disk drive.
1-4

1.2.15 Displ~Lamps
Two lamps on the front panel provide a visual display of the
ready and busy states of the disk drive.
1.2.16 Front Panel
The front panel holds the display lamps and provides an
attractive appearance for the front of the disk drive.
1.2.17 Movable Door Handle
The movable door handle ,when closed, engages the collet
assembly.
1.2.18 Door Lock Solenoid
The door lock solenoid (not shown) makes it impossible to
remove the flexible disk during certain drive operations,
theieby preventing data loss or physical damage to the
flexible disk.
1.3 SPECIFICATIONS
Table 1-1 lists the specifications for the Model FDl165
Flexible Disk Drive.
Table 1-1 FDl165 Specifications
FEATURES
SPECIFICATIONS
SINGLE-SIDED
DUAL-SIDED DUAL-SIDED
SINGLE-DENSITY SINGLE-DENSITY
DUAL-DENSITY
Unformatted Capacity
400 800 1600
(Kbytes)
Formatted Capacity
Sectors/track 26 15 8
26 15 8 26
15 8
By tes/ sec tor
128 256 512 128 256 512 256 512 1024
Bytes/track
3328 3840 4096 3328 3840 4096 6656 7680
8192
I< by tes/D isk 246 284 303 493 568 606 985 1137 1212
Media
IBM Diskette 1 IBM Diskette 2
IBM Diskette 20
or equivalent
or equivalent or equivalent
Media Dimensions
8 x 8/203
x203
(
inches/rom)
Tracks Per Disk
77 154 154
Bit Density
3268 3408 6816
(bits per inch)
Transfer Rate
31.25
31.25
62.5
(Kbytes per second)
Recording Method
FM
FM
MFM
1-5

Table 1-1
FDl165 Specifications (cont'd)
FEATURES
Track Density
(tracks per inch)
Rotational Speed
(rpm)
Access Times (ms)
Track-to-track
Seek settling time
Head load time
Latency time (average)
Start time
SINGLE-SIDED I
SINGLE-DENSITY
SPECIFICATIONS
DUAL-SIDED I
SINGLE-DENSITY
48
360
3.0
IS .5
30.0
83.3
700.0
DUAL-SIDED
DUAL-DENSITY
Power Requirements
Power Consumption
Physical dimensions
Height
Width
Depth
Weight
Environment requirements
Ambient temperature
Operating
Nonoperating
Relative humidity
Operating
Reliabili ty
Mean Time Between Failures
Mean Time to Repair
Soft Error Rates
Hard Error Rates
Seek Error Rates
+24 Vdc ±10% @ 0.9 Amp (maximum)
+5 Vdc ±5% @ 0.8 Amp (maximum) without VFO/
0.9 Amp (maximum) with VFO
26 Watts (27 Watts with VFO)
2.28 in. (58 rom)
8.55 in. (217.2 mm)
13.19 in. (335 rom)
7.7 pounds (3.5 Kg)
50°F to 113°F (10°C to 45°C)
23°F to 158°F (-5°C to 70°C)
20% to 80%
24,000 Power On Hours (POH)
0.5 hours
1 bit in 109
1 bit in 1012
1
in 106
1-6