Tandy 6000 HD, Service Manual

Page: 282 / 416

STEPPER MOTOR POWER
(PS, PS*, DS, HL)
W h e n th e P S ju m p e r is in s ta lle d , s te p p e r
m o to r p o w e r is c o n tr o lle d b y th e D r iv e S e le c t
lin e , D S , o r th e H e a d L o a d lin e , H L . W h e n
e it h e r lin e is t r u e (lo w ), th e s te p p e r m o to r is
d r iv e n w i t h f u l l p o w e r, a n d is re a d y f o r a Seek,
R ead, o r W r it e o p e ra tio n . W h e n e it h e r lin e is
fa ls e ( h ig h ) , + 5 v o l t s ta n d -b y c u r r e n t is s u p ­
p lie d t o th e s te p p e r m o to r to h o ld th e h e a d c a r ­
r ia g e a s s e m b ly i n p o s itio n . W h e n th e P S *
o p tio n is in , th e s te p p e r m o to r c o n tin u o u s ly
re c e iv e s f u l l p o w e r. P S * is d ia m e t r ic a lly o p p o ­
s ite P S (see F ig u r e 3 -3 ).
PS PS* DS HL STEPPER POWER
— X — — S te p p e r p o w e r
c o n tin u o u s ly on.
X — X — S te p p e r p o w e r o n w i t h
D r iv e S e le ct.
X — — X S te p p e r p o w e r o n w i t h
H e a d L o a d lin e J l- 1 8 .
SPINDLE MOTOR CONTROL OPTIONS
(M1, M3, M4, MOL, MOH, MC1 -M C 4 )
M l is used to e n a b le th e m o to r o f f d e la y tim e r .
W h e n t h is ju m p e r is in s ta lle d , a f iv e second
t u r n o f f d e la y o f th e s p in d le m o to r is a c tiv a te d
on th e t r a i l i n g edge o f th e M o t o r C o n tro l
s ig n a l.
W it h M o to r C o n tr o l u s in g D r iv e S e le c t o r
H e a d L o a d , th e M 3 a n d M 4 ju m p e r s d e te r m in e
w h ic h m e th o d o f M o to r C o n tr o l is e n a b le d . I f
o p tio n M 3 o r M 4 ju m p e r s a re in s ta lle d , th e
M o to r O n C o n tro l, M C I — M C 4 , o p tio n s o p e ra te
i n a lo g ic a l O R m a n n e r w i t h th e c o n tr o l
s ig n a l(s ) s e le c te d b y th e M 3 a n d M 4 ju m p e r s .
N O T E
I f th e M o to r D e la y T im e r o p tio n
( M l ) is i n s t a lle d , t h e f i v e
second t u r n o f f d e la y is i n e ffe c t
re g a rd le s s o f w h ic h M 3 /M 4 c o n ­
f ig u r a t io n is im p le m e n te d .
Ml M3 M4 MOTOR CONTROL
X — — E n a b le s fiv e -s e c o n d
m o to r o f f d e la y t im e r .
— — — M o to r C o n tr o l o n ly
w i t h M C I — M 4 o p tio n s .
— X — M o to r C o n tr o l u s in g
D r iv e S e le c t.
— — X M o to r C o n tr o l u s in g
H e a d L o a d .
— X X M o to r C o n tr o l u s in g
D r iv e S e le c t a n d H e a d
L o a d , lo g ic a l A N D .
MOL MOH MCI MC2 MC3 MC4 MOTOR CONTROL
X — — — — — M o to r C o n tr o l s ig n a ls a re lo w
( tr u e ) a c tiv e .
— X — — — — M o to r C o n tr o l s ig n a ls a re h ig h
( tr u e ) a c tiv e .
X — X — — — M o to r C o n tro l s e le c te d v ia J l - 4 .
X — — X — — M o to r C o n tr o l s e le c te d v ia J l - 6 .
X — — — X — M o to r C o n tr o l s e le c te d v ia J l - 8 .
X — — — — X M o to r C o n tr o l s e le c te d v ia J l - 24.
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