Yamaha GX-505 Service Manual page 38

A B
GX-505/GX-505VCD
PRINTED CIRCUIT BOARD (Foil side)
1
GX-505 CD P.C.B.
(Lead Type Device)
2
LED (CA)
LED (AN)
POS SW
ROTMTR (+)
COLLE
ROTMTR (–)
OPEN SW
CLOSE SW
TUDN SW
GND
LOADMTR (–)
LOADMTR (+)
TUUP SW
3
1/2VCC
VCC
E
D
A
B
C
F
LDGND
LD
VR
PD
FO (+)
TR (+)
TR (–)
FO (–)
4
5
FROM : INPUT (3)
40
6
C
FROM : CD MECHA.
FROM : INPUT (1)
FROM : MAIN (1)
D E
GX-505 CD P.C.B.
(Surface Mount Device)
1 2
Point q (Pin59 of IC5)
V : 2V/div H : 50 nsec/div
DC range 1 : 1 probe
0V
41
F G
Point w (Pin39 of IC8)
H : 0.1 µsec/div
V : 2V/div
DC range 1 : 1 probe
0V
H
Semiconductor Location
Ref. No. Location Ref. No. Location
D1 F2 IC1 F2
D2 E2 IC2 B3
D4 E4 IC3 B3
D5 E4 IC4 E4
D6 E4 IC5 F3
D7 E4 IC7 B4
IC8 F3
IC9 F4
IC10 F4
IC13 G4
IC14 G4
Ref. No. Location
Q1 C1
Q2 B3
Q3 C1
Q4 B3
Q5 C4
Q6 B4
Q7 B4
Q8 B5
Q9 B4
Q10 B5
Q11 C5
Q12 C5
Q13 C4