Tandy 6000 HD, Руководство по обслуживанию

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ACTIVITY INDICATOR
The a c tiv ity in d ic a to r is located o n the fr o n t panel
o f the d rive . I t is a u to m a tic a lly illu m in a te d w hen
the d riv e is selected.
AIR FILTRATION
A self-co n ta in e d , re c irc u la tin g a ir filtr a tio n system
supplies clean a ir th ro u g h a 0 .3 -m ic ro n filte r . A
secondary absolute filte r is p ro v id e d to a llo w
pressure
e q u a liza tio n w ith the a m b ie n t a t­
m osphere w ith o u t c o n ta m in a tio n . T h e e n tire
h e a d -d isk-a ctu a to r c o m p a rtm e n t is m a in ta in e d at
a s lig h tly p o sitive pressure to fu th e r ensure an
ultra cle a n e n v iro n m e n t.
1.4
FUNCTIONAL DESCRIPTION
T he d riv e is fu lly self-co n ta in e d and requires no
o p e ra to r in te rv e n tio n d u rin g n o rm a l o p e ra tio n .
D u rin g th e p o w e r-u p sequence, the spindle m o to r
reaches 3600 R P M , a n d th e p o s itio n in g
m echanism recalibrates th e re co rd in g heads back
to T ra c k 0. A t th is tim e , a Ready signal o n th e in ­
terface indicates th e d riv e is ready fo r o p e ra tio n .
T he head is p o sitio n e d over the desired tra c k by
means o f a four-phase stepper m o to r/b a n d
assembly and its associated electronics. T h is p o s i­
tio n e r uses a one-step ro ta tio n to cause a o n e -tra ck
ra d ia l m ovem ent. S ubsequently, the re co rd in g
heads can be p o sitio n e d over the desired cylinders,
and th e data can be read o r w ritte n fro m the ap­
p ro p ria te tra c k b y selecting the desired head.
T y p ic a lly , the d rive uses M F M w rite and read
re co rd in g m ethods. D ata recovery electronics in ­
clude a lo w -le ve l read a m p lifie r, d iffe re n tia to r, a
zero-crossover detector, and d ig itiz in g circuits. N o
data decoding feature is p ro v id e d o n th e drives.
The d rive has the fo llo w in g sensor systems:
1. A n o p tic a l T ra c k 0 sw itch senses w hen the
H e a d /C a rria g e A ssem bly is p o sitio n e d at
T ra c k 0.
2. A n in d e x sensor, w h ich consists o f a
m agnetic p ic k -u p and in d e x hole p o s itio n ­
ed to p ro v id e an analog signal w hen an in ­
dex hole is detected.
1.5
PHYSICAL DESCRIPTION
T he T M 5 0 0 d riv e is show n in F igure 1-1. T he
drives c o n ta in 130 m illim e te r storage m e d ia th a t
ro ta te at 3600 R P M , using a d ire c t d riv e , brushless
D . C . m o to r. The recording is accom plished b y
n o n co n ta ct standard recording heads th a t are
m oved b y a precisio n s p lit b and p o s itio n in g device
and stepper m o to r.
FIGURE 1-1
DISK DRIVE
The H ead D is k A ssem bly is enclosed in a sealed
cast a lu m in u m housing , w h ic h includes an a ir
filtr a tio n system to ensure a c o n ta m in a tio n -fre e
e n v iro n m e n t. The housing is shock m o u n te d to a
m e ta l fra m e th a t has the fr o n t panel attached, and
threaded holes on the sides and b o tto m fo r m o u n t­
ing the drive o n to a chassis.
In a d d itio n , the d riv e includes the re a d /w rite c o n ­
tr o l electronics, the servo spindle c o n tro l elec­
tro n ic s , an in d e x sensor, a brake assembly, and a
fr o n t panel in d ic a to r.