Tandy 1000 SL Technical Reference Manual page 463

(C) Check and adjustment procedure (General method)
(1) U s e two channels of an o s c i l l o s c o p e and connect them
t o
TP7 and TP8
( D i f f e r e n t i a t i o n amp.) on t h e PCBA
MFD
c o n t r o l . Also connect t h e
e x t e r n a l t r i g g e r o f t h e o s c i l l o s c o p e t o TP1 (Index) and apply p o s i t i v e
t r i g g e r .
Oscilloscope range:
AC
mode, 0.2 0.54, 20msec
S e t both channels, 1 and
2
t o t h e above ranoe. S e t e i t h e r of t h e
channels t o I n v e r t mode and Add b o t h c h a n n e l s .
( 2 ) I n s t a l l an alignment d i s k and s t a r t t h e s p i n d l e motor.
( 3 ) Execute t h e head l o a d i n g .
(4) S e t t h e head t o t h e following alignment check t r a c k .
Alignment check t r a c k , 4 8 t p i (FD-55BR)
:
Track 16
9 6 t p i (FD-SSFWGR)
:
Track 32
(5)
Confirm t h a t two l o b e p a t t e r n s a s i n Fig.3418 can be observed ( i t
is
n o t necessary t h a t t h e l e v e l s of
VA
and VB a r e e q u a l ) .
T P ~
and TP8 (Add)
4 8 t p i
9 6 t p i
(Fig.3418) Alignment check l o b e p a t t e r n
If
only
one
l o b e p a t t e r n can be observed o r i f two l o b e s become one
-
3451
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