Philips MC-20 Service Manual page 30

RECORDER BOARD ETF6 (Analog) - CIRCUIT DIAGRAM
1 2
3735
REC_L
22K
PLAY BACK
3
DECK A A A
L
1730
A
L
3703
1
220R
2
A
L
3
A
L
L
4 3704
220R
3736
REC_R
22K
A A
B
3701
5
220R REC in
3702
REC/PB
DECK B
220R
1710
1
100K
#
2
C 3785
3
4
5
A
6
7786
J111
A
3784 A
1K 3781
-C
4M7
D
6773
2786 3780
100p 1M
1N4148
+12
A
3762
820R
E
BC557B P
7782
P 7783
BC847B
MT1 7 8 MT2
3770 3771
6
3
1K5 1K2
5
2
2782
1 4
3777
F 4n7
CLNS-2A833 YEZ
150R 3776
5703
6K8
2743
ERASE
22n
A P
OSCILLATOR
A A P
1 2
PCS 104 198
11-3
3 4
2727
1n
3723
*
12K LEFT CHANNEL 3705
220R
7710 MODE
HEF4952B SELECTOR
15 7
A0 1A0
+C 2715
A
16 9
S0
3707
A1 1A1
14 10
S1
A2
12
S2
100R
220u
11 S3 8
S4 -C 3764
+12
VSS
2 4
VEE 220R
1 S0 A
A
3 S1 13
VDD
5 S2
6 S3
RIGHT
S4
A
CHANNEL
A
3706
220R
A2 A1 A0 S0 S1 S2 S3 S4
STOP 0 0 0 1 1
3708
Pb deck A 0 0 1 1 1 A
Pb deck B 0 1 0 1 1
-- 0 1 1 1 1 1 100R
1 0 0 1 1 3712
Dubbing 1
1 0 1 1
-- 1 1 0 1 1
150K
--
1 1 1 1
2734
6775
470p
1N4148
BIAS
SYMM 3787
2721
1M
#
7785
A
# J111
5702
B1
2u2
A
P
PB SWITCH
2722
A
3779
330K REC B2
6774
1N4148 A
A A
+C
3761
* 10K
A
* 6778
3769
BIAS
CRB
LEVEL
12K
1N4148
+12
6776
3752
P
100K
1N4148
*
3786
P
7780
7781
BC847B
22K
REC
BC817-25
P P
P P
3 4
5 6
2713
3711 3741
150K 3763 2K2
10u
2733
9793
LH
150K
5
12
470p
PC2 PC1 3713
10
2711
IN2
10R
A
13
OUT2 100p
11
2737
NF2
A
14
AN2
100n
16 7720
Vcc
ALCEN
2
AN7318S
ALCC
3765
PB/REC
1
AMPLIFIER
39K
GND
A
15 3
RF AIN1
7
2738
IN1
4
3714
OUT1 100n
6
NF1 10R
NC1 NC2
8 9
3742
A
A
2K2
2719 2717
3721 LH
5K6
33n 10n
3719 3717
3725 4K7 2K2
15 7
10R 3A0
6n8 A0
16 S0 9
2723
A1 REC
14 10
S1
A2 CRB
12
S2
15n 2741
11 S3 8
S4
P
A
VSS 22n
A
2 4
3726 VEE
-C
1
S0
3 S1 13
10R VDD
6n8 +C
5 S2
2724
6 S3 7730
S4
HEF4952B
15n
* 3724 2720 3722 2718
12K 5K6
33n 10n
2728
3720 3718
4K7 2K2
1n
REC EQUALISATION A2 A1 A0 S0 S1 S2 S3 S4
1
NS Ferro 0 0 0 1
HS Ferro 0 0 1 1 1
REC MUTE 0 1 0 1 1
+5
REC MUTE
0 1 1 1 1 1
NS Chrome 1 0 0 1 1
HS Chrome 1
1 0 1 1
REC MUTE 1 1 0 1 1
-- 1 1 1 1
1A1
7791
BC847B
P
L Not For Single Deck Variant
* See Variant Table for details
# For Provision Only
1A0
ANALOG CCTR
5 6
11-3
7 8
B1
2729
3727
9791
5K6
27n B3
3731
7740
HEF4952B
6K8
15 7
A0 2A0
16 9
S0
3729
A1 2A1
14 10
S1
3760
A2 2A2
12
S2
2K7
11 S3 8
120R S4
A
VSS
2 4
-C
3732 VEE
1 S0
3 S1 13
6K8
VDD +C
5 S2
3730
6 S3
S4
2K7
3728 2730
9792
A
B4
5K6
27n
A2 A1 A0
-- 0 0 0
STOP
0 0 1
-- 0 1 0
B2 REC 0 1 1
HS Chrome 1 0 0
ALCEN
Pb Chrome 1 0 1
--
1 1 0
6782
Pb Ferro 1 1 1
1A0
3748
1N4148
7787
BC847B
3749 2K2
REC
A
47K
+5
CONTROL LOGIC
7792 3756
CRA
BC847B
2A0 220K
3757
HS
220K
P
P
3754
3A0 HS
1M
1
M 3768
-C
3746 10K
B4
12V
3K3
+12
3745
B3
3K3
A
REC_R
*
*
A REC_L
A A A
4
3139 118 51470 sh 130-2 dd wk901
7 8
9
1701 F9 3716 B6 5703 F1
1710 C1 3717 C6 6770 E2
1730 A1 3718 D6 6771 E2
2701 B2 3719 C6 6772 D1
2702 B2 3720 D6 6773 D1
2703 A2 3721 C6 6774 D3
2704 B2 3722 D6 6775 C3
A 2705 A2 3723 A3 6776 F3
2706 A2 3724 D5 6777 E2
A
2707 A4 3725 C5 6778 E4
P
2708 B4 3726 D5 6782 C7
2709 A5 3727 A7 6785 A7
M
2710 B5 3728 B7 6786 B7
2711 A6 3729 A7 7710 A3
2712 B6 3730 B7 7720 A5
2713 A6 3731 A7 7730 D6
2714 B6 3732 A7 7740 A8
PLAYBACK
2715 A4 3733 A2 7780 F4
EQUALISATION
2716 C4 3734 B2 7781 F3
2717 C6 3735 A2 7782 E1
2718 D6 3736 B1 7783 E2
B
2719 C5 3741 A6 7784 D2
2720 D5 3742 B7 7785 C3
S0 S1 S2 S3 S4 2721 C5 3743 F8 7786 C2
1 1
2722 D5 3744 F8 7787 C8
1
1
2723 C5 3745 F8 7791 F5
1
1
2724 D5 3746 E8 7792 D8
1 1 1
1 1
2725 D4 3748 C8 9791 A8
1 1
2726 D4 3749 C7 9792 B8
1 1
2727 A3 3751 E5 9793 A6
1
2728 D5 3752 F5
C
2729 A8 3753 F5
2730 B8 3754 E8
2733 A5 3755 E7
2734 C4 3756 D8
2735 B3 3757 D8
2737 A6 3758 D8
2738 B6 3759 D7
2741 D6 3760 A7
2742 C3 3761 E3
2743 F1 3762 E2
2744 A3 3763 A5
D
2760 E3 3764 A5
2761 B5 3765 B6
2762 B6 3766 B7
2763 B6 3767 A7
2765 B4 3768 E8
2769 F7 3769 E4
2770 F7 3770 F2
2780 F3 3771 F2
2781 F2 3772 F3
2
2782 F2 3773 E3
E
2784 F1 3774 E3
2785 F1 3775 F2
-CMOS
7
2786 D1 3776 F2
TAPE-R 2787 D3 3777 F2
6
3701 B1 3778 E1
+12V
5
3702 B2 3779 D3
TAPE-L 3703 A2 3780 D2
4
3781 D2
3704 A1
GND_A
3
3705 A4 3782 C2
3706 B4 3784 D1
2 REC-R
F
3707 A5 3785 C2
REC-L
1
3708 B4 3786 F4
3709 A4 3787 C3
1701
3710 C4 3788 C3
TO/FROM AF
3711 A5 3789 F3
3 3712 B4 4790 C2
3713 A7 4794 C6
3714 B7 5701 D2
3715 A6 5702 C2
9