Kenwood DP-1100 B Service Manual page 37

1 - 5 - 2 T R A Y O P E R A T I O N
1 . W h e n tray OPEN/CLOSE s w i t c h S 0 0 4 is p r e s s e d , Q1
m o m e n t a r i l y t u r n s o n a n d a key s c a n n i n g signal available
f r o m pin 13 of IC1 is a p p l i e d t o pin 2 9 of I C 1 .
2 . The signal p u t t h r o u g h pin 2 9 is p r o c e s s e d in IC1 a n d its
o u t p u t is c o u p l e d t o pin 3 9 of IC15 ( T M P 4 7 4 0 N )
t h r o u g h pin 4 0 .
3 . T h e data signal fed t h r o u g h pin 3 9 c o n t r o l s pin 1 to 5 in
I C 1 5 . (An i n s t r u c t i o n signal t o IC15 ( T C 1 5 G or T 7 0 0 1 )
is d e v e l o p e d by a c o m b i n a t i o n of pin 1 t o 5.)
^ \ T R A Y ^ \ T R A Y
Remarks
OPENS C L O S E S
C o n t r o l ^ C o n t r o l ^
Refer to control MODE of
Mode Mode
I C 1 5 ( T C 1 5 G 0 0 8 A P )
E F 8 C
P i n ^ ^ P i n ^ ^ Table 2-2B and notes
below.
1 L H L L
2 H H L L
3 H H L H
4 H H H H
L L
5 L L
'Notes on Control Mode in Tray OPEN/CLOSE operation
E: The SLT (start limit) switch Is ON, i.e. the tray is retracted and the
pickup is moved toward the center of the disc till pickup start limit
switch is on. This occurs when the tray is retracted with or without
disc by OPEN/CLOSE switch.
F: The SLT switch is OFF. This occurs in the state other than mentioned
above such as in PLAY mode or PAUSE mode during playback.
8: The laser diode is ON. This occurs when the tray is closed by pressing
PLAY button or any kind of music selection or playback button.
C: The laser diode is OFF. This occurs when the tray is closed by pressing
OPEN/CLOSE switch.
4 0
D P - 1 1 0 0 B II D P - 1 1 0 0 B II
1. CIRCUIT DESCRIPTION
4 . W h e n the p o w e r is t u r n e d o n a n d tray OPEN/CLOSE
s w i t c h is p r e s s e d , the tray o p e n s . W h e n the s w i t c h is
pressed a g a i n , it closes. T h e o p e r a t i o n is repeated alter­
nately by every pressure of OPEN/CLOSE s w i t c h ( S 0 0 4 )
5. T h e OPEN/CLOSE f u n c t i o n of the tray is a c h i e v e d by
c o m b i n a t i o n s of " H " a n d " L " levels at pin 1 t o 5 of
IC15 ( T M P 4 7 4 0 N ) as s h o w n b e l o w .
6. T h e o u t p u t s f r o m pin 1 t o 5 of IC15 ( T M P 4 7 4 0 N ) are
applied t o pin 2 4 t o 2 7 a n d 3 0 , a n d the o u t p u t is t h e n
available at pin 9 of IC15 ( T C 1 5 G or T 7 0 0 1 ) .
7. Pin 9 of IC15 ( T C 1 5 G of T 7 0 0 1 ) has a high i m p e d a n c e
for the c o n d i t i o n s other t h a n the listed left. T h e i n p u t t o
pin 3 of IC3 is + 2 . 5 V , w h i c h is o b t a i n e d by d i v i d i n g
+ 5 V w i t h R 6 8 a n d R 7 1 . T h e + 5 V is also d i v i d e d by
R 6 6 a n d R 6 7 to provide pin 4 of IC3 w i t h + 2 . 5 V . T h e
c o m p a r a t i v e d i f f e r e n c e b e t w e e n v o l t a g e s at pin 3 a n d 4
of IC3 is available at pin 2 as an o u t p u t . Since the
voltages at pin 3 a n d 4 are the s a m e + 2 . 5 V , the resul­
t a n t o u t p u t at pin 2 b e c o m e s 0 V. W h e n t h e v o l t a g e at
pin 2 of IC3 is 0 V , Q 1 5 a n d Q 1 6 are OFF a n d t h e tray
m o t o r d o e s n o t run w i t h n o p o w e r s u p p l i e d .
8 . W h e n the tray o p e n s , pin 9 of IC15 ( T C 1 5 G or T 7 0 0 1 )
is at " L " level. It pulls d o w n the potential at pin 3 of IC3
f r o m 2 . 5 V d o w n t o w a r d g r o u n d . The inverted o u t p u t
c h a n g i n g ( f r o m 0 V) t o w a r d plus a p p e a r s at pin 2 . It
t u r n s o n Q 1 5 . T h e m o t o r revolves in the c l o c k w i s e direc­
t i o n . ( Q 1 5 a n d Q 1 6 p r e v e n t o v e r l o a d i n g of pin 2 of IC3.)
Fig. 1 - 5 - 3
9. W h e n the tray c l o s e s , pin 9 of IC15 ( T C 1 5 G of T 7 0 0 1 )
is at " H " level. It p u s h e s the v o l t a g e at pin 3 of IC3 f r o m
2 . 5 V up t o w a r d p o w e r s u p p l y v o l t a g e . W h e n
v o l t a g e at pin 3 b e c o m e s higher t h a n t h a t of pin 4
( 2 . 5 V ) , the inverted o u t p u t c h a n g i n g ( f r o m 0 V) t o w a r d
m i n u s a p p e a r s at pin 2 . It t u r n s o n Q 1 6 (while Q 1 5 is
OFF), p r o v i d i n g the tray m o t o r w i t h a m i n u s v o l t a g e ,
w h i c h c o m e s f r o m - 1 2 V line t h r o u g h R72 a n d L 2 .
T h e m o t o r revolves in t h e c o u n t e r c l o c k w i s e d i r e c t i o n .
1 0 . W h e n the OPEN/CLOSE f u n c t i o n of the tray is c o m p l e t e d
by pressing the tray OPEN/CLOSE S w i t c h , a leaf s w i t c h
p r o v i d e d o n the tray t u r n s O N or OFF. T h e state of the
s w i t c h is given t o IC15 ( T M P 4 7 4 0 N ) t o c o n t r o l the
signals at pin 1 t o 5 a n d the m o t o r stops r e v o l v i n g .
the