Tandy 1000 Technical Reference Manual

Tandy 1000
Technical Reference Manual
The DO motor is an outor-rotor type DC brushless motor which has the
long life of 20,000 hours or more in continuous rotation.
The rotational speed is 300rpm and maintains stable rotational speed
against load variations and environmental changes. This is achieved
by a feedback signal from the internal AC tachometer.
The precisely combined collet and spindle are attached at the correct
angle to maintain the center position correctly without damaging the
center hole of the disk and so as to make the head be in contact with
disk at the correct angle.
(4) Magnetic head and carriage
Read/write
core
Read/write core
Erase cores
Read/write gap
Tunnel erase type head Straddle erase type head
(Fig.302) External view of magnetic head core
For single sided FDDs, the external view of the magnetic head is button
shaped and it is mounted on the carriage so that it is in contact
with the SIDE 0 (the buttom side when the FDD is placed horizontally)
head window area of the disk.
For double sided FDDs, both the SIDE 1 head and the SIDE 0 head are
special flat type supported with the gimballed mechanisms. The two
magnetic heads are mounted accross the disk on one carriage.
In both types of head, the surface is designed for minimum disk wear
and maximum read output. The head itself is a long life type for
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Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200