Tandy 1000 Technical Reference Manual

Tandy 1000
4-4-7. Check and Adjustment of Asymmetry
(A) Equipment
(1) Work disk
(2) SKA or user's system
(3) Oscilloscope
(B) Check and adjustment procedure
(1) General method
Technical Reference Manual
(a) Connect an oscilloscope to TP5 (Read data) on the PCBA MFD control
or to the READ DATA interface line.
Oscilloscope range : DC mode, 2V, l~sec
(b) Start the spindle motor and install a work disk.
(c) Set the head to the innermost track.
(d) Execute IF write operation (125KHz of WRITE DATA frequency).
(e) Measure the asymmetry referring to Fig.421.
Note: Oscilloscope should be so set that three read data pulses can be
observed. Asymmetry width should be measured at the second read
data pulse from the trigger pulse.
(f) Confirm that the asymmetry is within the following range.
Innermost rrack IF asymmetry : O.6~sec, Max.
(g) For a double sided FDD, execute items (d) through (f) for the side 0
and the side 1 heads respectively.
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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