Write Protect Sensor Check; Drive Motor Speed Check; Radial Track Alignment Check And Adjustment; Radial Track Alignment Check - Tandy 6000 Service Manual

4. V e r if y th e p o w e r s u p p ly v o lta g e s a re
w i t h i n to le ra n c e s .
5. E n s u re a d r iv e
p la c e .
6. S e le c t th e d r iv e .
7. V e r if y th e f r o n t p a n e l L .E .D . is i l l u ­
m in a te d
8. D e s e le c t th e d riv e .
9. E n s u r e t h e
e x tin g u is h e s .
5.4 WRITE PROTECT SENSOR
CHECK
T h e w r it e p r o te c t sensor c h e c k e s ta b lis h e s th e
c o rre c t o p e ra tio n o f th e w r it e p ro te c t sensor,
i.e., th e w r it e e le c tro n ic s a re d is a b le d w h e n a
w r it e p ro te c te d d is k e tte is used. I f th e sensor
is f a u lt y , r e fe r to th e tro u b le s h o o tin g g u id e .
1. C o n n e c t th e d r iv e to a n e x e rc is e r o r
c o m p u te r w it h a d ir e c t m o n ito r o f th e
w r it e p r o te c t o u tp u t ( P I, P in 4 4).
2. W it h a n o n w r it e
in s e rte d , v e r if y
p ro te c te d o u tp u t to th e e x e rc is e r, i.e., a
h ig h a t P I , P in 44.
3. W i t h a w r i t e
in s e rte d , v e r if y th e re is a w r it e p r o te c t
t r u e o u t p u t
e x e rc is e r, i.e., a lo w a t P I , P in 44.
N O T E
A d e fe c tiv e c ir c u it b o a rd c a n be
re s p o n s ib le f o r a w r it e p ro te c t
p ro b le m . T e s t P o in t 5 s h o u ld be
h ig h f o r a w r i t e
d is k e tte , lo w
p ro te c te d d is k e tte .
5.5 DRIVE MOTOR SPEED
CHECK
T h e d r iv e m o to r 's speed c h e c k e n s u re s th e
speed is w i t h in th e s p e c ifie d to le ra n c e . T h e
m o to r speed is 360 R P M ±
m o to r speed is o u t o f to le ra n c e , r e f e r to th e
o ro u b le s h o o tin g g u id e .
s e le ct ju m p e r is in
f r o n t p a n e l L .E .D .
p ro te c te d d is k e tte
th e r e is a n o n w r ite
p r o t e c t e d d is k e t t e
to th e c o n t r o lle r o r
p r o te c te d
f o r a n o n w r ite
1.5 p e rc e n t. I f th e
1. A p p ly p o w e r to th e d riv e .
2. In s e r t a w o r k d is k e tte .
3. A c tiv a te th e d r iv e m o to r.
4. O b se rve th e t im in g d is k on th e d r iv e
m o to r u n d e r a m b ie n t flu o re s c e n t l i g h t ­
in g ( F ig u re 5-2).
5. V e r if y th e 60 H e r tz r in g is s ta tio n a r y .
5.6 RADIAL TRACK
ALIGNMENT CHECK AND
ADJUSTMENT
T h e R a d ia l T r a c k a lig n m e n t p ro c e d u re lo c a te s
th e r e a d /w r ite h e a d a t th e p ro p e r r a d ia l d is ­
ta n c e on th e h u b c e n te r lin e , e n s u rin g th e
tr a c k lo c a tio n is a c c u ra te (F ig u re 5-3). A d ju s t ­
m e n t is n e ce ss a ry o n ly a f t e r s e r v ic in g o r i f
d is k e tte in te rc h a n g e p ro b le m s a re suspected.
I f th e c a ts eye p a t t e r n c a n n o t be v e r ifie d o r
c a n n o t be a d ju s te d , r e fe r to th e tro u b le s h o o t­
in g g u id e .
A lig n m e n t d is k e tte
m u s t be a llo w e d to s ta b iliz e a t
ro o m te m p e r a tu r e f o r one h o u r
b e fo re ch e cks a n d a d ju s tm e n ts
a re m ade .

RADIAL TRACK ALIGNMENT CHECK

1. S e t u p th e oscillo sco p e to re a d :
C h a n n e l A : U 2 , P in 14
C h a n n e l B : U 2 , P in 15
G ro u n d : T e s t P o in t 8
R ea d D if f e r e n t ia lly : A p lu s B , B
T im e B a se : 20 m illis e c o n d s p e r d iv is io n
E x t e r n a l T r ig g e r : T e s t P o in t 10,
2. A d ju s t th e a m p litu d e f o r a t le a s t fo u r
d iv is io n s on th e o scillosco pe .
3. A p p ly p o w e r to th e d riv e .
5-3
N O T E
a n d d r iv e
in v e r te d
p o s itiv e edge