McIntosh C42 User manual

AUDIO CONTROL CENTER
BALANCE
@
FECORO
@@@@@@@@@
LISIEN
2
VOLUME
llltlnlogh
C42 AUDIO CONTROL CENTER
LRLINE 1
-
LINÈ2-O
@
35 70 150 300 600 1.2k 4k
o
?g5
CONIENIS
Performance Specifications ..........
Notes .........
Rear Panel
Section Locations
Block Diagram ...................
lnterconnection Diagram ...
Main Schematic and PCB...
Balanced Schematic
Display Schematic and PCB
Tone Schematic and PCB ...
Data Schematic and PCB ...
Parts List.....
Exploded View and Parts List...
Repacking lnstructions
...6-1
2
2
3
3
4
5
7
.... 1B-20
....21-24
....25-26
....27-28
....29-31
....32-34
......... 35
mlntû5h
SERVICE MANUAL

PE RF O RMAN CE S PEC I F I CAT IONS
FREQUENCY RESPONSE
. +0, -0.5d8 Írom 2OHz to 20,000H2
TOTAT HARMONIC DISTORTION
O.OO2% maximum Írom 2OHz to 20,000H2
SICNAT TO NOISE RATIO
Phono: S6dB (A Weighted)
High Level: 97dB (Aweighted)
RATED OUTPUT VOTTAGE
Main and Outputs 1 and 2:2.5Vrms
MAXIMUM VOTTAGE OUTPUT
Main and Outputs 1 and 2:1OVrms
OUTPUT IMPEDANCE
240 ohms
INPUT IMPEDANCE
Phono:47k ohms, 65pf
High Level: 22k ohms
SENS¡TIVITY
Phono:4.5mV for rated output
High Level: 450mV for rated output
MAXIMUM INPUT S¡CNAI
Phono:5OmV
High Level:5V
VOTTAGE GAIN
Phono to Tape Out:40d8
High Level to Tape Out:OdB
High Level to Main Out: 15dB
POWER REQUTREMENTS
1 O0Volts, 5O/60H2, 30 Watrs
1 1 OVolts, 5Ol6OHz, 30 Watrs
1 20Volts, 5Ol6OHz, 30 Watts
22oVolts, 5O/6OHz, 30 Watts
230Volts, 5O/6OHz, 30 Watts
240Volts, 5Ol6OHz, 30 Watrs
Note: Refer to the rear panel of the C42 for
the correct voltage
DIMENSIONS
Width: 17-1/2 inches (44.5cm)
Height: 5-3lB inches (13.7cm)
Depth: 1B-1/2 inches (44.5cm) ,including
clearance for connectors
NOTES
1 . The heavy notes on the schematic denote
the primary signal path.
2. Unless otherwise noted, all voltages
indicated on the schematics are measured
under the following conditions:
a. AC input af "l2O volts, 50/60H2.
b. All voltages are +/-10% with respect to
ground. A high impedance (10 megaohm)
voltmeter must be used.
3. Unless otherwise specified:
a. Resistor values are in ohms.
b. Capacitor values are microfarads (uF).
c. lnductor values are in microhenries (uH)
4. On PC board drawings, Square pad
indicates:
a. Polarized Capacitors - Positive
b. Diodes - Cathode
c. Others - Pin 1
5. WARNINC: ^
Parts marked with the symbol ,/ ! \ have
critical characteristics. Use only replacement
parts recommended by the manufacturer.
2

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REAR PAAVET
SECTIOAV LOCAIION5
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DISPLAY
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MAIN
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MAIN
OUTPUTS
c169
F*
K42 8223
221 10
71
c1
+
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K41
K¿3
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tr
K40
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5vl
c 115 F24
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c1 73
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DATA
A
A *o**,"G: Parts locatecl in the shaclecl
area have critical characteristics Use ONLY
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manufacturer.
EXTERNAL
sENSÕR
J17
NEGATIVÉ 24 VOLT
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10
c12?
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c 139
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c74
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3-
8194
024
Bl 99
595CLK2
CTFLEN2
SDATA
AECORO
DECODEB
595CLK
CIFLEN
al 78
1k
14

5CLK
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lc35 16=5V
8=GND
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lLINE2.L
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(3of 4) o+næ
DECODER
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0
D
tr
c203

PCB o4erge
....fa
a
a
a
tr
a
a
a
tr
a
a
tr
a
a
!
J10
GE
aa ÉÊ
aa aa
tr
Ê
a
,13
J9
JB
J1-
o
J4
ÈE
oo
20

a
a
a
tr
a
a
tr
aaaaa
!
a
a
tr
ÉE
aa
c
tr
t-J
J3
J7
J6 J5
J2-
o
rG
EE
Jt0
LEFT
LINE/CD1
J9 INPUTS
RIGHT
R2
221 J7
2
MAIN
J4
1 tgrr
J3
OUTPUÏS
R1 J6
2
MAIN
J8
1 RtGHt
3
810
K3
K2
K1
K6
5V
5V
R8
:u
R7
5V
R9
221
R4
221
3
R5
221
R11
3
R12
K4
5V
R6
K5
5V
K7
K8
5V
5V
R3
221
J5
19

BALANCED o4elBe t
o
O
c
z
o
ts
J1-1
J1-2
J1"3
J1-1 0V
Jt-2 0v
J 1-3
J1-4 0V
Jl-s 0v
R +BAL
J1-4
J1-5
I
R .BAL
LEFT +
J2-5
5V
RIGHT J2-2
OUTPUT
GND J2-
J2-4
J2-5
J2-3
J2-2
J2-1
J2-6
J2-7
,t2-a
OV
5V
6
o
È
z
o
F
It
OV
OUIPUT
2
5V
r'"ttl
vv
L
1B