Page 1
POWER AMPLIFIER
CONTENTS
Performance Specifications ........................................ 2
Notes ......................................................................... 2
Rear Panel .................................................................. 3
Section Location ........................................................ 5
Block Diagram ........................................................... 6
Interconnection Diagram ...................................... 7 - 8
Input Schematic and PCB.................................... 9 - 12
Heatsink 1-Channel Schematic and PCB ............ 13 - 18
SERVICE MANUAL
Heatsink 2-Channel Schematic and PCB ............ 21 - 26
Display Schematic and PCB ............................... 29 - 32
Capacitor Schematic and PCB .................................. 33
Power Supply Schematic and PCB..................... 34 - 35
Parts List ............................................................ 36 - 42
Exploded Views and Parts Lists .......................... 43 - 46
Repacking Instruction .............................................. 47
Page 2
PERFORMANCE SPECIFICATIONS
Power Output
Minimum sine wave continuous average power output per 
channel, all channels operating is:   200 watts into 4 ohm or 
8 ohm load
Rated Power Band
20Hz to 20,000Hz
Total Harmonic Distortion
Maximum Total Harmonic Distortion at any power level from 
250 milliwatts to rated power output is:  0.005% for 4 or 8 
ohm loads
Dynamic Headroom
1.7dB
Frequency Response
+0, -0.25dB from 20Hz to 20,000Hz 
+0, -3dB from 10Hz to 100,000Hz
Sensitivity
1.0 Volt Unbalanced with a 4 ohm Loudspeaker
2.0 Volt Balanced with a 4 ohm Loudspeaker
1.4 Volt Unbalanced with a 8 ohm Loudspeaker
2.8 Volt Balanced with a 8 ohm Loudspeaker
A-Weighted Signal To Noise Ratio
89dB (112dB below rated output)
Intermodulation Distortion
Maximum Intermodulation Distortion if instantaneous peak 
output per channel does not exceed twice the rated output, for 
any combination of frequencies from 20Hz to 20,000Hz, with 
all channels operating is:   0.005% for 4 or 8 ohm loads
Input Impedance
20,000 ohms Balanced 
10,000 ohms Unbalanced
Wide Band Damping Factor
Greater than 60 at 4 ohms 
Greater than 140 at 8 ohms
Power Requirements
100 Volts, 50/60Hz at 1440 watts 
110 Volts, 50/60Hz at 13.0 amps 
120 Volts, 50/60Hz at 12.0 amps 
220 Volts, 50/60Hz at  6.0 amps 
230 Volts, 50/60Hz at  6.0 amps 
240 Volts, 50/60Hz at  6.0 amps
Note: Refer to the rear panel of the MC207 for the correct voltage.
Dimensions
Front Panel: 17-1/2 inches (44.45cm) wide, 9-7/16 inches 
(23.97cm) high. Depth behind front mounting panel is 
18-3/4 inches (47.63cm), including clearance for connectors.
Weight
83 pounds (37.6kg) net, 116 pounds (52.6kg) in shipping carton
1. The heavy lines 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 at 120 volts, 50/60Hz. 
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. Inductor values are in microhenries (uH).
NO TES
4.  On PC board drawings, Square pad indicates: 
a. Polarized Capacitors - Positive 
b. Diodes - Cathode 
c. Others - Pin 1
5.  WARNING 
Parts marked with the symbol       have critical 
characteristics. Use only replacement parts recommended by the manufacturer.
2
Page 3
REAR PANEL
MC207
3
Page 4
NOTES
4
Page 5
SECTION LOCATIONS
MC207
TOP VIEW
TOP VIEW WITH COVER REMOVED
5
Page 6
BLOCK DIAGRAM
6
Page 7
MC207
1
INTERCONNECT
7  8
Page 8
2
INPUT 
050065
9  10
Page 9
MC207
2
INPUT 
050065
11  12
Page 10
3
A 
B
HEATSINK 1-CHANNEL 
050070
13  14
Page 11
3
MC207
A 
B
HEATSINK 1-CHANNEL 
DRIVER SECTION 050070
15  16
Page 12
3
A 
B
HEATSINK 1-CHANNEL 
050070
* Denotes components on reverse or backside of PC Board.
17  18
Page 13
NOTES
MC207
19  20
Page 14
4
A 
B 
C
HEATSINK 2-CHANNEL 
050064
21  22
Page 15
4
MC207
A 
B 
C
HEATSINK 2-CHANNEL
 DRIVER SECTION 050064
23  25
Page 16
3
4
A 
B 
C
HEATSINK 2-CHANNEL 
050064
5
DISPLAY 
ILLUMINATION SECTION 050066
A 
B
* Denotes components on reverse or backside of PC Board.
26  28
Page 17
MC207
5
DISPLAY 
METER SECTION 050066
5
DISPLAY 
POWER GUARD SECTION 050066
29  30
Page 18
5
DISPLAY 
050066
* Denotes components on reverse or backside of PC Board.
31  32
Page 19
MC207
6
CAPACITOR 
050063
* Denotes components on reverse or backside of PC Board.
33
Page 20
7
POWER SUPPLY 
050062
34
Page 21
MC207
7
POWER SUPPLY 
050062
35
Page 22
PARTS LIST
Ref 
No.  Description
1
050065 INPUT PCB 
C1  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C2  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C3  CAP MONO 47PF 200V 10% NPO 
061299 
C4  CAP MONO 47PF 200V 10% NPO 
061299 
C5  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C6  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C7  CAP MONO .1uF 50V 20% Z5U 
061305 
C8  CAP MONO .1uF 50V 20% Z5U 
061305 
C9  CAP MONO 22PF 200V 10% NPO 
061298
2
C10  CAP MONO 22PF 200V 10% NPO 
061298 
C11  CAP MONO 47PF 200V 10% NPO 
061299 
C12  CAP ELECT 10UF 50V  066445 
C13  CAP MONO 47PF 200V 10% NPO 
061299 
C14  CAP ELECT 10UF 50V  066445 
C15  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C16  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C17  CAP MONO 47PF 200V 10% NPO 
061299 
C18  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C19  CAP MONO 47PF 200V 10% NPO 
061299 
C20  CAP MONO .1uF 50V 20% Z5U 
061305 
C21  CAP MONO .1uF 50V 20% Z5U 
061305 
C22  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C23  CAP MONO 22PF 200V 10% NPO 
061298 
C24  CAP MONO .1uF 50V 20% Z5U 
061305 
C25  CAP MONO .1uF 50V 20% Z5U 
061305 
C26  CAP MONO 47PF 200V 10% NPO 
061299 
C27  CAP MONO 22PF 200V 10% NPO 
061298
Part 
No.
C28  CAP MONO 47PF 200V 10% NPO 
061299 
C29  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C30  CAP MONO 47PF 200V 10% NPO 
061299 
C31  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C32  CAP MONO 22PF 200V 10% NPO 
061298 
C33  CAP MONO 47PF 200V 10% NPO 
061299 
C34  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C35  CAP MONO 47PF 200V 10% NPO 
061299 
C36  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C38  CAP MONO 22PF 200V 10% NPO 
061298 
C39  CAP MONO .1uF 50V 20% Z5U 
061305 
C40  CAP MONO .1uF 50V 20% Z5U 
061305 
C41  CAP MONO 47PF 200V 10% NPO 
061299 
C43  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C44  CAP MONO 47PF 200V 10% NPO 
061299 
C45  CAP ELECT 10UF 16V 4X5 CASE 
066382 
C46  CAP MONO 22PF 200V 10% NPO 
061298 
C47  CAP MONO 22PF 200V 10% NPO 
061298 
J1  CONN MALE 9 POS FRICTION LOCK 
117244 
J2  JACK RCA BLK  117847 
J3  JACK RCA 1X2 BLK/BLK 14MM 
117848 
J4  CONN 4 PIN  117215 
J5  CONN 4 PIN  117215 
J6  RECEPTACLE XLR FEMALE  117685 
J7  RECEPTACLE XLR FEMALE  117685 
J8  JACK RCA 1X2 BLK/BLK 14MM 
117848 
J9  CONN 4 PIN  117215 
J10  CONN D 25-PIN  117501 
J11  CONN 4 PIN  11721 
J12  RECEPTACLE XLR FEMALE  117685 
J13  RECEPTACLE XLR FEMALE  117685
36
Page 23
PARTS LIST con’t
MC207
J14  RECEPTACLE XLR FEMALE  117685 
J16  JACK RCA 1X2 BLK/BLK 14MM 
117848 
J17  CONN 4 PIN  117215 
J18  RECEPTACLE XLR FEMALE  117685 
J19  “JACK HEADPHONE DUAL BLACK 1/ 
8””,117825"”” 
J20  RECEPTACLE XLR FEMALE  117685 
R1  RES MF 1K 1% 1/4W 144090 
R2  RES MF 1K 1% 1/4W 144090 
R3  RES MF 20K 1% 1/4W  144104 
R4  RES MF 221 OHM 1% 1/4W  144172 
R5  RES MF 20K 1% 1/4W  144104 
R6  RES MF 221 OHM 1% 1/4W  144172 
R7  RES MF 100K 1% 1/4W  144113 
R8  RES MF 100K 1% 1/4W  144113 
R9  RES MF 20K 1% 1/4W  144104 
R10  RES MF 20K 1% 1/4W  144104 
R11  RES MF 10K 1% 1/4W  144053 
R12  RES MF 10K 1% 1/4W  144053 
R13  RES MF 10 OHM 1% 1/4W  144157 
R14  RES MF 10K 1% 1/4W  144053 
R16  RES MF 100K 1% 1/4W  144113 
R17  RES MF 10K 1% 1/4W  144053 
R18  RES MF 100K 1% 1/4W  144113
3A
R19  RES MF 10 OHM 1% 1/4W  144157
3B
R20  RES MF 1K 1% 1/4W 144090 
R21  RES MF 20K 1% 1/4W  144104 
R22  RES MF 221 OHM 1% 1/4W  144172 
R23  RES MF 1K 1% 1/4W 144090 
R24  RES MF 100K 1% 1/4W  144113 
R25  RES MF 20K 1% 1/4W  144104 
R26  RES MF 20K 1% 1/4W  144104 
R27  RES MF 221 OHM 1% 1/4W  144172 
R28  RES MF 100K 1% 1/4W  144113 
R29  RES MF 10K 1% 1/4W  144053 
R30  RES MF 20K 1% 1/4W  144104 
R31  RES MF 10K 1% 1/4W  144053 
R33  RES MF 100K 1% 1/4W  144113 
R34  RES MF 10K 1% 1/4W  144053 
R35  RES MF 10K 1% 1/4W  144053 
R37  RES MF 100K 1% 1/4W  144113 
R38  RES MF 1K 1% 1/4W 144090 
R39  RES MF 20K 1% 1/4W  144104 
R40  RES MF 221 OHM 1% 1/4W  144172 
R41  RES MF 100K 1% 1/4W  144113 
R42  RES MF 20K 1% 1/4W  144104 
R43  RES MF 10K 1% 1/4W  144053 
R44  RES MF 10K 1% 1/4W  144053 
R45  RES MF 100K 1% 1/4W  144113 
R46  RES MF 100 OHM 1% 1/4W  144196 
R47  RES MF 1K 1% 1/4W 144090 
R48  RES MF 20K 1% 1/4W  144104
R49  RES MF 221 OHM 1% 1/4W  144172 
R50  RES MF 100K 1% 1/4W  144113 
R51  RES MF 20K 1% 1/4W  144104 
R55  RES MF 10K 1% 1/4W  144053 
R56  RES MF 10K 1% 1/4W  144053 
R58  RES MF 100K 1% 1/4W  144113 
R59  RES MF 1K 1% 1/4W 144090 
R60  RES MF 20K 1% 1/4W  144104 
R61  RES MF 221 OHM 1% 1/4W  144172 
R62  RES MF 100K 1% 1/4W  144113 
R63  RES MF 20K 1% 1/4W  144104 
R64  RES MF 100 OHM 1% 1/4W  144196 
R65  RES MF 10K 1% 1/4W  144053 
R66  RES MF 10K 1% 1/4W  144053 
R68  RES MF 100K 1% 1/4W  144113 
S1  SWITCH SLIDE  148059 
SP1  BRACKET PCB CARD MOUNTING 
003611 
U1  IC DUAL OPERATIONAL AMPLIFIER 
133260 
U2  IC DUAL OPERATIONAL AMPLIFIER 
133260 
U3  IC DUAL OPERATIONAL AMPLIFIER 
133260 
U4  IC DUAL OPERATIONAL AMPLIFIER 
133260
050064 HEATSINK1 PCB 
C1  CAP ELECT 47UF 35V  066446 
C2  CAP ELECT 47UF 35V  066446 
C3  CAP MONO .1uF 50V 20% Z5U 
061305 
C4  CAP POLYPROP 0.15UF 10% 250VDC 
064363 
C7  CAP MONO 100PF 100V 10% NPO 
061300 
C8  CAP MONO 100PF 100V 10% NPO 
061300 
C9  CAP MONO .01UF 50V 20% X7R 
061304 
C14  CAP MONO 100PF 100V 10% NPO 
061300 
C16  CAP MONO .01UF 50V 20% X7R 
061304 
C22  CAP ELECT 220UF 25V  066507 
C27  CAP MONO 100PF 100V 10% NPO 
061300 
C30  CAP ELECT 47UF 35V  066446 
C31  CAP ELECT .47UF 50V  066244 
C32  CAP MONO .1uF 50V 20% Z5U 
061305 
C33  CAP MONO .1uF 50V 20% Z5U 
061305
37
Page 24
PARTS LIST con’t
C35  CAP ELECT 10UF 100VDC  066462 
C36  CAP ELECT 10UF 100VDC  066462 
C37  CAP ELECT 10UF 100VDC  066462 
C38  CAP ELECT 10UF 100VDC  066462 
C40  CAP ELECT 220UF 50V 20% 066254 
C41  CAP ELECT 10UF 100VDC  066462 
C47  CAP POLYPROP .047UF 10% 250VDC 
064364 
C51  CAP ELECT 10UF 100VDC  066462 
C200  CAP ELECT 10UF 100VDC  066462 
D1  DIODE SILICON  070047 
D2  DIODE SILICON  070047 
D4  DIODE SILICON  070047 
D5  DIODE SILICON  070047 
D6  DIODE RECTIFIER  070131 
D7  DIODE RECTIFIER  070131 
IC2  IC DUAL AMP 133259 
J1  CONN MALE 9 POS FRICTION LOCK 
117244 
J2  CONN 4 PIN  117215 
J4  CONN HEADER 2 PIN 0.156 117404 
J5  BLADE FASTON .110 117712 
J6  BLADE FASTON W/FEET  117708 
J8  CONN HEADER 2 PIN 0.156 117404 
J9  CONN 2 PIN MALE  117213 
K1  RELAY 24VDC 5A 277VAC  087057 
K2  RELAY 24VDC 5A 277VAC  087057 
L2  CHOKE 0.65UH OUTPUT  122297 
LD1  LDR NETWORK VTL5C9  144179 
Q1  TRANSISTOR NPN  132223 
Q2  TRANSISTOR PNP  132224 
Q3  TRANSISTOR NPN  132268 
Q4  TRANSISTOR PNP  132267 
Q5  TRANSISTOR NPN  132223 
Q6  TRANSISTOR NPN 25C3334C 132285 
Q7  TRANSISTOR PNP 2SA32IC  132286 
Q8  TRANSISTOR PNP POWER  132297 
Q9  TRANSISTOR NPN POWER  132296 
Q10  TRANSISTOR PNP POWER  132297 
Q11  TRANSISTOR NPN POWER  132296 
Q20  TRANSISTOR NPN POWER  132296 
Q22  TRANSISTOR PNP POWER  132297 
Q23  TRANSISTOR NPN POWER  132296 
Q25  TRANSISTOR PNP POWER  132297 
Q27  TRANSISTOR PNP  132224 
Q29  TRANSISTOR PNP POWER  132255 
Q30  TRANSISTOR SI NPN 25V  132254 
Q31  TRANSISTOR NPN  132223 
Q32  TRANSISTOR NPN  132223
4A
Q33  TRANSISTOR PNP POWER  132255
4B
Q35  TRANSISTOR NPN  132223
4B
Q37  TRANSISTOR NPN 25C3334C 132285 
Q39  TRANSISTOR PNP 2SA32IC  132286
Q41  TRANSISTOR PNP  132224 
Q49  TRANSISTOR PNP  132224 
Q50  TRANSISTOR NPN  132223 
Q51  TRANSISTOR NPN  132223 
Q52  TRANSISTOR NPN  132223 
Q53  TRANSISTOR PNP POWER  132255 
Q54  TRANSISTOR PNP  132224 
Q55  TRANSISTOR PNP POWER  132255 
Q56  TRANSISTOR PNP POWER  132255 
Q59  TRANSISTOR NPN  132223 
Q60  TRANSISTOR SI NPN 25V  132254 
Q61  TRANSISTOR SI NPN 25V  132254 
Q63  TRANSISTOR NPN  132223 
Q64  TRANSISTOR PNP POWER  132255 
R1  RES MF 332 OHM 1% 1/4W  144446 
R2  RES MET OX 680 OHM 5% .5W 
137093 
R3  RES MF 22.1K 1% 1/4W  144187 
R4  RES MF 100K 1% 1/4W  144113 
R5  RES MF 22.1K 1% 1/4W  144187 
R6  RES MET OX 1.8k 5% .5W  137094 
R7  RES MET OX 430 OHM 5% .5W 
137095 
R8  RES MF 332 OHM 1% 1/4W  144446 
R9  RES MET OX 680 OHM 5% .5W 
137093 
R10  RES MF 22.1K 1% 1/4W  144187 
R11  RES MET OX 1.8k 5% .5W  137094 
R12  RES MET OX 47 OHM 5% .5W 
137096 
R13  POT TRIM 200 OHM 20% HORIZ AD 
134390 
R14  RES MF 100K 1% 1/4W  144113 
R15  RES MF 100 OHM 1% 1/4W  144196 
R16  RES MF 100 OHM 1% 1/4W  144196 
R17  RES MF 100 OHM 1% 1/4W  144196 
R30  RES MF 475K 1% 1/4W  144364 
R32  RES MF 47.5K 1% 1/4W  144108 
R33  RES MF 47.5K 1% 1/4W  144108 
R34  RES MF 5.11K 1% 1/4W  144083 
R36  RES 511 OHM 1% 1/4W  144123 
R37  RES MF 681K 1% 1/4W  144443 
R38  RES MF 866 OHM 1% 1/4W  144028 
R39  RES MF 2.21 OHM 1/4W 1% 144378 
R41  RES WW DUAL .47 OHM 5% 3W 
139244 
R42  RES WW DUAL .47 OHM 5% 3W 
139244 
R43  RES WW DUAL .47 OHM 5% 3W 
139244 
R45  RES WW DUAL .47 OHM 5% 3W 
139244 
R46  RES MF 4.75K 1% 1/4W  144097
38
Page 25
PARTS LIST con’t
MC207
R48  RES MF 100 OHM 1% 1/4W  144196 
R50  RES MF 14.7K 1% 1/4W  144149 
R51  RES MF 221 OHM 1% 1/4W  144172 
R52  RES MF 267K 1% 1/4W  144118 
R53  RES MF 221 OHM 1% 1/4W  144172 
R54  RES MF 3.32K 1% 1/4W  144095 
R55  RES MF 3.32K 1% 1/4W  144095 
R56  RES MF 10K 1% 1/4W  144053 
R57  RES MF 475K 1% 1/4W  144364 
R58  RES MF 1.1K 1% 1/4W  144091 
R59  RES MF 2.21 OHM 1/4W 1% 144378 
R60  RES FP 22 OHM 1/4W 5%  137033 
R62  RES MF 22.1K 1% 1/4W  144187 
R63  RES FP 22 OHM 1/4W 5%  137033 
R65  RES MF 681K 1% 1/4W  144443 
R67  RES MF 100 OHM 1% 1/4W  144196 
R70  RES MF 100 OHM 1% 1/4W  144196 
R71  RES MF 100 OHM 1% 1/4W  144196 
R72  RES MF 100 OHM 1% 1/4W  144196 
R77  RES MF 1M 1/4W  144269 
R79  RES CF 10 OHM 5% 1/2W  141165 
R82  RES MF 1M 1/4W  144269 
R83  RES MF 10K 1% 1/4W  144053 
R84  RES MF 47.5K 1% 1/4W  144108 
R85  RES MF 1.1K 1% 1/4W  144091 
R86  RES MF 4.75K 1% 1/4W  144097 
R88  RES MF 12.1K 1% 1/4W  144154 
R90  RES MF 1.1K 1% 1/4W  144091 
R93  RES MF 4.75K 1% 1/4W  144097 
R101  RES MF 953 OHM 1/4W 1%  144473 
R103  RES MF 332K 1% 1/4W  144119 
R104  RES MF 15K 1% 1/4W  144412 
R105  RES MF 6.49K 1% 1/4W  144140 
R106  RES MF 475 OHM 1% 1/4W  144086 
R109  RES CF 0 ohm  141389 
R111  RES MET OX 430 OHM 5% .5W 
137095 
R114  RES CF 10 OHM 5% 1/2W  141165 
R119  RES MO 4.7 OHM 1W 5%  144464 
R122  RES MF 47.5K 1% 1/4W  144108 
R123  RES MF 22.1K 1% 1/4W  144187 
R124  RES MF 47.5K 1% 1/4W  144108 
RT1  THERMAL  144249 
RT2  THERMAL  144249
050064 HEATSINK2 PCB 
C1  CAP ELECT 47UF 35V  066446 
C2  CAP ELECT 47UF 35V  066446 
C3  CAP MONO .1uF 50V 20% Z5U 
061305 
C4  CAP POLYPROP 0.15UF 10% 250VDC 
064363
C7  CAP MONO 100PF 100V 10% NPO 
061300 
C8  CAP MONO 100PF 100V 10% NPO 
061300 
C9  CAP MONO .01UF 50V 20% X7R 
061304 
C10  CAP ELECT 47UF 35V  066446 
C11  CAP ELECT 47UF 35V  066446 
C12  CAP MONO 100PF 100V 10% NPO 
061300 
C13  CAP MONO 100PF 100V 10% NPO 
061300 
C14  CAP MONO 100PF 100V 10% NPO 
061300 
C15  CAP MONO .1uF 50V 20% Z5U 
061305 
C16  CAP MONO .01UF 50V 20% X7R 
061304 
C17  CAP MONO .01UF 50V 20% X7R 
061304 
C18  CAP MONO .01UF 50V 20% X7R 
061304 
C19  CAP MONO 100PF 100V 10% NPO 
061300 
C22  CAP ELECT 220UF 25V  066507 
C27  CAP MONO 100PF 100V 10% NPO 
061300 
C28  CAP MONO 100PF 100V 10% NPO 
061300 
C29  CAP ELECT 47UF 35V  066446 
C30  CAP ELECT 47UF 35V  066446 
C31  CAP ELECT .47UF 50V  066244 
C32  CAP MONO .1uF 50V 20% Z5U 
061305 
C33  CAP MONO .1uF 50V 20% Z5U 
061305 
C35  CAP ELECT 10UF 100VDC  066462 
C36  CAP ELECT 10UF 100VDC  066462 
C37  CAP ELECT 10UF 100VDC  066462 
C38  CAP ELECT 10UF 100VDC  066462 
C39  CAP ELECT .47UF 50V  066244 
C40  CAP ELECT 220UF 50V 20% 066254 
C41  CAP ELECT 10UF 100VDC  066462 
C44  CAP ELECT 220UF 25V  066507 
C47  CAP POLYPROP .047UF 10% 250VDC 
064364 
C48  CAP POLYPROP .047UF 10% 250VDC 
064364 
C50  CAP ELECT 10UF 100VDC  066462 
C51  CAP ELECT 10UF 100VDC  066462 
C200  CAP ELECT 10UF 100VDC  066462 
D1  DIODE SILICON  070047 
D2  DIODE SILICON  070047
39
Page 26
PARTS LIST con’t
D4  DIODE SILICON  070047 
D5  DIODE SILICON  070047 
D6  DIODE RECTIFIER  070131 
D7  DIODE RECTIFIER  070131 
D8  DIODE SILICON  070047 
D9  DIODE SILICON  070047 
D11  DIODE SILICON  070047 
D12  DIODE SILICON  070047 
D13  DIODE RECTIFIER  070131 
D14  DIODE RECTIFIER  070131 
IC1  IC DUAL AMP 133259 
IC2  IC DUAL AMP 133259 
J1  CONN MALE 9 POS FRICTION LOCK 
117244 
J2  CONN 4 PIN  117215 
J3  CONN HEADER 2 PIN 0.156 117404 
J4  CONN HEADER 2 PIN 0.156 117404 
J5  BLADE FASTON .110 117712 
J6  BLADE FASTON W/FEET  117708 
J8  CONN HEADER 2 PIN 0.156 117404 
J9  CONN 2 PIN MALE  117213 
J10  CONN 2 PIN MALE  117213 
K1  RELAY 24VDC 5A 277VAC  087057 
K2  RELAY 24VDC 5A 277VAC  087057 
L1  CHOKE 0.65UH OUTPUT  122297 
L2  CHOKE 0.65UH OUTPUT  122297 
LD1  LDR NETWORK VTL5C9  144179 
LD2  LDR NETWORK VTL5C9  144179 
Q1  TRANSISTOR NPN  132223 
Q2  TRANSISTOR PNP  132224 
Q3  TRANSISTOR NPN  132268 
Q4  TRANSISTOR PNP  132267 
Q5  TRANSISTOR NPN  132223 
Q6  TRANSISTOR NPN 25C3334C 132285 
Q7  TRANSISTOR PNP 2SA32IC  132286 
Q8  TRANSISTOR PNP POWER  132297 
Q9  TRANSISTOR NPN POWER  132296 
Q10  TRANSISTOR PNP POWER  132297 
Q11  TRANSISTOR NPN POWER  132296 
Q12  TRANSISTOR NPN  132223 
Q13  TRANSISTOR PNP  132224 
Q14  TRANSISTOR NPN  132223 
Q15  TRANSISTOR PNP 2SA32IC  132286 
Q16  TRANSISTOR NPN 25C3334C 132285 
Q17  TRANSISTOR PNP  132267 
Q18  TRANSISTOR NPN  132268 
Q19  TRANSISTOR NPN POWER  132296 
Q20  TRANSISTOR NPN POWER  132296 
Q21  TRANSISTOR PNP POWER  132297 
Q22  TRANSISTOR PNP POWER  132297 
Q23  TRANSISTOR NPN POWER  132296 
Q24  TRANSISTOR NPN POWER  132296 
Q25  TRANSISTOR PNP POWER  132297
5
Q26  TRANSISTOR PNP POWER  132297 
Q27  TRANSISTOR PNP  132224 
Q28  TRANSISTOR SI NPN 25V  132254 
Q29  TRANSISTOR PNP POWER  132255 
Q30  TRANSISTOR SI NPN 25V  132254 
Q31  TRANSISTOR NPN  132223 
Q32  TRANSISTOR NPN  132223 
Q33  TRANSISTOR PNP POWER  132255 
Q34  TRANSISTOR NPN  132223 
Q35  TRANSISTOR NPN  132223 
Q36  TRANSISTOR NPN 25C3334C 132285 
Q37  TRANSISTOR NPN 25C3334C 132285 
Q38  TRANSISTOR PNP POWER  132255 
Q39  TRANSISTOR PNP 2SA32IC  132286 
Q40  TRANSISTOR PNP  132224 
Q41  TRANSISTOR PNP  132224 
Q42  TRANSISTOR NPN  132223 
Q43  TRANSISTOR PNP  132224 
Q44  TRANSISTOR PNP POWER  132255 
Q45  TRANSISTOR PNP POWER  132255 
Q46  TRANSISTOR PNP  132224 
Q47  TRANSISTOR SI NPN 25V  132254 
Q48  TRANSISTOR PNP 2SA32IC  132286 
Q49  TRANSISTOR PNP  132224 
Q50  TRANSISTOR NPN  132223 
Q51  TRANSISTOR NPN  132223 
Q52  TRANSISTOR NPN  132223 
Q53  TRANSISTOR PNP POWER  132255 
Q54  TRANSISTOR PNP  132224 
Q55  TRANSISTOR PNP POWER  132255 
Q56  TRANSISTOR PNP POWER  132255 
Q57  TRANSISTOR SI NPN 25V  132254 
Q58  TRANSISTOR NPN  132223 
Q59  TRANSISTOR NPN  132223 
Q60  TRANSISTOR SI NPN 25V  132254 
Q61  TRANSISTOR SI NPN 25V  132254 
Q62  TRANSISTOR PNP  132224 
Q63  TRANSISTOR NPN  132223 
Q64  TRANSISTOR PNP POWER  132255 
R1  RES MF 332 OHM 1% 1/4W  144446 
R2  RES MET OX 680 OHM 5% .5W 
137093 
R3  RES MF 22.1K 1% 1/4W  144187 
R4  RES MF 100K 1% 1/4W  144113 
R5  RES MF 22.1K 1% 1/4W  144187 
R6  RES MET OX 1.8k 5% .5W  137094 
R7  RES MET OX 430 OHM 5% .5W 
137095 
R8  RES MF 332 OHM 1% 1/4W  144446 
R9  RES MET OX 680 OHM 5% .5W 
137093 
R10  RES MF 22.1K 1% 1/4W  144187 
R11  RES MET OX 1.8k 5% .5W  137094
40
Page 27
PARTS LIST con’t
MC207
R12  RES MET OX 47 OHM 5% .5W 
137096 
R13  POT TRIM 200 OHM 20% HORIZ AD 
134390 
R14  RES MF 100K 1% 1/4W  144113 
R15  RES MF 100 OHM 1% 1/4W  144196 
R16  RES MF 100 OHM 1% 1/4W  144196 
R17  RES MF 100 OHM 1% 1/4W  144196 
R18  RES MET OX 47 OHM 5% .5W 
137096 
R19  RES MET OX 1.8k 5% .5W  137094 
R20  RES MF 332 OHM 1% 1/4W  144446 
R21  RES MF 22.1K 1% 1/4W  144187 
R22  RES MET OX 680 OHM 5% .5W 
137093 
R23  RES MET OX 430 OHM 5% .5W 
137095 
R24  RES MET OX 680 OHM 5% .5W 
137093 
R25  RES MF 22.1K 1% 1/4W  144187 
R26  RES MET OX 1.8k 5% .5W  137094 
R27  RES MF 332 OHM 1% 1/4W  144446 
R28  POT TRIM 200 OHM 20% HORIZ AD 
134390 
R29  RES MF 475K 1% 1/4W  144364 
R30  RES MF 475K 1% 1/4W  144364 
R31  RES MF 5.11K 1% 1/4W  144083 
R32  RES MF 47.5K 1% 1/4W  144108 
R33  RES MF 47.5K 1% 1/4W  144108 
R34  RES MF 5.11K 1% 1/4W  144083 
R35  RES MF 47.5K 1% 1/4W  144108 
R36  RES 511 OHM 1% 1/4W  144123 
R37  RES MF 681K 1% 1/4W  144443 
R38  RES MF 866 OHM 1% 1/4W  144028 
R39  RES MF 2.21 OHM 1/4W 1% 144378 
R40  RES WW DUAL .47 OHM 5% 3W 
139244 
R41  RES WW DUAL .47 OHM 5% 3W 
139244 
R42  RES WW DUAL .47 OHM 5% 3W 
139244 
R43  RES WW DUAL .47 OHM 5% 3W 
139244 
R44  RES WW DUAL .47 OHM 5% 3W 
139244 
R45  RES WW DUAL .47 OHM 5% 3W 
139244 
R46  RES MF 4.75K 1% 1/4W  144097 
R47  RES MF 4.75K 1% 1/4W  144097 
R48  RES MF 100 OHM 1% 1/4W  144196 
R49  RES MF 1.1K 1% 1/4W  144091 
R50  RES MF 14.7K 1% 1/4W  144149 
R51  RES MF 221 OHM 1% 1/4W  144172
R52  RES MF 267K 1% 1/4W  144118 
R53  RES MF 221 OHM 1% 1/4W  144172 
R54  RES MF 3.32K 1% 1/4W  144095 
R55  RES MF 3.32K 1% 1/4W  144095 
R56  RES MF 10K 1% 1/4W  144053 
R57  RES MF 475K 1% 1/4W  144364 
R58  RES MF 1.1K 1% 1/4W  144091 
R59  RES MF 2.21 OHM 1/4W 1% 144378 
R60  RES FP 22 OHM 1/4W 5%  137033 
R61  RES MF 100 OHM 1% 1/4W  144196 
R62  RES MF 22.1K 1% 1/4W  144187 
R63  RES FP 22 OHM 1/4W 5%  137033 
R64  RES MF 10K 1% 1/4W  144053 
R65  RES MF 681K 1% 1/4W  144443 
R66  RES MF 681K 1% 1/4W  144443 
R67  RES MF 100 OHM 1% 1/4W  144196 
R68  RES MF 475K 1% 1/4W  144364 
R69  RES MF 22.1K 1% 1/4W  144187 
R70  RES MF 100 OHM 1% 1/4W  144196 
R71  RES MF 100 OHM 1% 1/4W  144196 
R72  RES MF 100 OHM 1% 1/4W  144196 
R73  RES MF 100 OHM 1% 1/4W  144196 
R74  RES MF 100 OHM 1% 1/4W  144196 
R75  RES MF 267K 1% 1/4W  144118 
R76  RES MF 221 OHM 1% 1/4W  144172 
R77  RES MF 1M 1/4W  144269 
R78  RES MF 100 OHM 1% 1/4W  144196 
R79  RES CF 10 OHM 5% 1/2W  141165 
R80  RES CF 10 OHM 5% 1/2W  141165 
R81  RES MF 100 OHM 1% 1/4W  144196 
R82  RES MF 1M 1/4W  144269 
R83  RES MF 10K 1% 1/4W  144053 
R84  RES MF 47.5K 1% 1/4W  144108 
R85  RES MF 1.1K 1% 1/4W  144091 
R86  RES MF 4.75K 1% 1/4W  144097 
R87  RES MF 14.7K 1% 1/4W  144149 
R88  RES MF 12.1K 1% 1/4W  144154 
R89  RES MF 953 OHM 1/4W 1%  144473 
R90  RES MF 1.1K 1% 1/4W  144091 
R91  RES MF 681K 1% 1/4W  144443 
R92  RES MF 866 OHM 1% 1/4W  144028 
R93  RES MF 4.75K 1% 1/4W  144097 
R94  RES MF 47.5K 1% 1/4W  144108 
R95  RES MF 1.1K 1% 1/4W  144091 
R96  RES MF 3.32K 1% 1/4W  144095 
R97  RES 511 OHM 1% 1/4W  144123 
R98  RES MF 3.32K 1% 1/4W  144095 
R99  RES MF 221 OHM 1% 1/4W  144172 
R100  RES MF 1.1K 1% 1/4W  144091 
R101  RES MF 953 OHM 1/4W 1%  144473 
R102  RES MF 332K 1% 1/4W  144119 
R103  RES MF 332K 1% 1/4W  144119 
R104  RES MF 15K 1% 1/4W  144412
41
Page 28
PARTS LIST con’t
R105  RES MF 6.49K 1% 1/4W  144140 
R106  RES MF 475 OHM 1% 1/4W  144086 
R107  RES MF 475 OHM 1% 1/4W  144086 
R108  RES MF 6.49K 1% 1/4W  144140 
R109  RES CF 0 ohm  141389 
R110  RES MET OX 430 OHM 5% .5W 
137095 
R111  RES MET OX 430 OHM 5% .5W 
137095 
R112  RES MF 1M 1/4W  144269 
R113  RES CF 10 OHM 5% 1/2W  141165 
R114  RES CF 10 OHM 5% 1/2W  141165 
R115  RES MF 1M 1/4W  144269 
R119  RES MO 4.7 OHM 1W 5%  144464 
R120  RES MO 4.7 OHM 1W 5%  144464 
R122  RES MF 47.5K 1% 1/4W  144108 
R123  RES MF 22.1K 1% 1/4W  144187 
R124  RES MF 47.5K 1% 1/4W  144108 
RT1  THERMAL  144249 
RT2  THERMAL  144249
050066 DISPLAY PCB 
C1  CAP ELECT 10UF 50V  066445 
C2  CAP MPF 0.47UF 5% 50/63VDC 
064333 
C3  CAP MONO .1uF 50V 20% Z5U
6
061305 
C4  CAP MONO .1uF 50V 20% Z5U 
061305 
C5  CAP MPF 0.1UF 5% 63VDC  064325 
C6  CAP ELECT 10UF 50V  066445 
C7  CAP MPF 0.47UF 5% 50/63VDC 
064333 
C8  CAP MONO .1uF 50V 20% Z5U 
061305 
C9  CAP MONO .1uF 50V 20% Z5U 
061305 
C10  CAP MPF 0.1UF 5% 63VDC  064325 
C11  CAP ELECT 10UF 50V  066445
7
C12  CAP MPF 0.47UF 5% 50/63VDC 
064333 
C13  CAP MONO .1uF 50V 20% Z5U 
061305 
C14  CAP ELECT 100UF 16V OR 25V 
066447 
C15  CAP MPF 0.1UF 5% 63VDC  064325 
C16  CAP MONO .1uF 50V 20% Z5U 
061305 
D1  DIODE SILICON  070047 
D2  DIODE SILICON  070047 
D3  DIODE SILICON  070047 
D4  DIODE SILICON  070047
D5  DIODE SILICON  070047 
D6  DIODE SILICON  070047 
D7  DIODE SILICON  070047 
D8  DIODE SILICON  070047 
D9  DIODE SILICON  070047 
D10  DIODE SILICON  070047 
D11  DIODE SILICON  070047 
D12  DIODE SILICON  070047 
D13  DIODE SILICON  070047 
D14  DIODE SILICON  070047 
D15  DIODE SILICON  070047 
D16  DIODE SILICON  070047 
D17  DIODE SILICON  070047 
D18  DIODE SILICON  070047 
D19  DIODE SILICON  070047 
D20  DIODE SILICON  070047 
D21  DIODE SILICON  070047 
D22  DIODE SILICON  070047 
D23  DIODE SILICON  070047 
D24  DIODE SILICON  070047 
D25  DIODE SILICON  070047 
D26  DIODE SILICON  070047 
D27  DIODE SILICON  070047 
D28  DIODE SILICON  070047 
D29  DIODE SILICON  070047 
D30  DIODE SILICON  070047 
DS1  LED BLUE 5MM HI-INTENSITY
“VF[V] 3.6”””  058166(1)112108(1)
DS2  LED BLUE 5MM HI-INTENSITY
“VF[V] 3.6”””  058166(1)112108(1)
DS3  LED GREEN 5MM HI-INTENSITY
“VF[V] 3.5”””  058165(1)112108(1)
DS4  LED GREEN 5MM HI-INTENSITY
“VF[V] 3.5”””  058165(1)112108(1)
DS5  LED RED HIGH EFFICIENCY 058148 
DS6  LED BLUE 5MM HI-INTENSITY
“VF[V] 3.6”””  058166(1)112108(1) 
DS7  LED BLUE 5MM HI-INTENSITY
“VF[V] 3.6”””  058166(1)112108(1) 
DS8  LED GREEN 5MM HI-INTENSITY
“VF[V] 3.5”””  058165(1)112108(1) 
DS9  LED GREEN 5MM HI-INTENSITY
42
Page 29
MC207 EXPLODED VIEW
MC207
43  44
Page 30
MC207 EXPLODED VIEW and PARTS LIST
Ref 
No.  Description
Part 
No.
1  016507  GLASS 
2  094360  TAPE FOAM 1/2 X 1/2 
3  004939  BRACKET EXTRUSION 
4  018615  END CAP 9” 
5  101042  SCREW TS 4-40 X 1/2 SLOT FILL 
6  094016  TAPE FOAM 1/4 X 1/8 
7  098113  CORD DIAL .027 BLACK BRAID SILK 
8  018706  EXTRUSION BOTTOM 
9  100149  SCREW MACH 6-32 X 1/4 FL U/H ST 
10  101232  SCREW 6-32 X 1/4 PH FLAT 
11  018619  EXTRUSION TOP 
12  104164  WASHER BLK FELT 1 X 1/4 X 1/16 
13  049321  ASSY KNOB 
14  092413  ACETATE FILTER BLUE DISPLAY 
15  005407  SUBPANEL 
16  017901  LOGO PUSHBUTTON BACKLIGHT 
17  017921  LOGO/SELECTOR BACKLIGHT 
18  094429  FOAM TAPE WHITE 1/32” THK 
19  146243  SWITCH POWER 
20  021159  BUSHING SWITCH 
21  104014  WASHER INT STAR 3/8 X .507 X .002 
22  124089  METER MC207 
23  017922  METER BACKLIGHT 
24  005411  METER PLATE 
25  102001  NUT KEP 4-40 CADMIUM PLATE 
26  050066  ASSY METER/DISPLAY PCB 
27  112038  SPACER STEEL 4 X 3/8L NCKL PLT 
28  112060  SP ACER 4 X 5/16 STEEL 
29  005404  DUST COVER 
30  100287  SCREW MACH 8-32 X 3/8 PH TRUSS HD 
31  126999  DECAL DUST COVER 
32  005408  CHASSIS 
33  101054  SCREW TAPTITE 6-32 X 1/4 PH PN BLK 
34  078024  GROMMET RUBBER 1” ID 
35  078040  GROMMET 3/4” X 1” 
36  017956  TRANSFORMER SHIELD 
37  050061  POTTED TRANSFORMER POWER 
38  166001  DECAL POWER TRANSFORMER 
39  050090  CAN POTTED CAPACITOR 
40  166002  DECAL CAPACITOR COVER 
41  094450  SOUND DAMPING PAD MC207 
42  050063  ASSY CAPACITOR PCB 
43  005413  CAPACITOR CLAMP 
44  102045  NUT KEP 6-32 X 1/2 PH PN 
45  100118  SCREW MACH 6-32 X 1/2 PH PN 
46  018750  HEATSINK 
47  084183  ISOSTRATE 
48  050064  ASSY HEATSINK PCB 2 CH 
49  101059  SCREW SM 6 X 5/8 PH PN TYPE A 
50  112087  SP ACER PCB 1/4”
51  114118  TRANSISTOR CLIP 218 
52  114119  TRANSISTOR CLIP 214 
53  005007  ASSY HEATSINK PCB 1 CH 
54  005439  COVER HEATSINK CH 5-6 
55  005406  HEATSINK COVER CENTER 
56  005405  COVER HEATSINK CH 1-3 
57  084124  POST BINDING DUAL 
58  005419  OUTPUT PLATE TRIPLE 
59  005418  OUTPUT PLATE SINGLE 
60  104130  WASHER LOCK #10 SPLIT PHOS/BRNZ 
61  104148  WASHER FLAT BRASS 
62  110009  NUT M5 X 0.8 BRASS W/GOLD PLATE 
63  074091  TERMINAL BLOCK AC 
64  005435  TERMINAL BRACKET 
65  104001  WASHER FLAT STEEL 4 X 9/32 X .025 
66  104142  WASHER LOCK 2.5mm INT STAR ZINC 
67  102022  NUT MACH 4-40 X 3/16 X 1/16 
68  114072  RIVET PLASTIC 
69  005434  TRANSFORMER BRACKET 
70  102003  NUT MACH 6-32 W/LOCK 
71  094255  CABLE TIE PANDUIT PLT1M-M 
72  017452  KLIP WIRE 
73  021094  SPACER 4 X 1/4 
74  104014  3/8 INT STAR WASHER 
75  084209  THERMSTRATE MC207 
76  102020  NUT MACH 6-32 SELF LOCK 
77  050062  ASSY POWER SUPPLY PCB 
78  018751  SUB HEATSINK 
79  114141  CLIP RIGHT ANGLE 
80  100250  SCREW MACH SEMS 6-32 X 1/4 PH PN 
81  084208  ISOSTRATE POWER SUPPLY 
82  005410  CHASSIS SUPPORT REAR 
83  070139  DIODE BRIDGE RECTIFIER 
84  084207  THERMAL PAD 1.25 X 1.25 ALUMINUM 
85  102006  NUT MACH 10-32 W/LOCK 
86  005401  HEATSINK VENT 
87  101176  SCREW TC 6-32 X 1/2 PH PN TYPE F 
88  005065  ASSY INPUT PCB 
89  088023  CIRCUIT BREAKER 10A 240VAC 
90  117487  RECEPT ACLE AC LINE 
91  100250  SCREW MACH SEMS 6-32 X 1/4 PH PN 
92  101197  SCREW HI-LO 4-24 X 3/8 PH RD BLK 
93  112015  STANDOFF 
94  104004  WASHER LOCK 5 X .255 INT STAR 
95  005400  BOTTOM COVER 
96  017937  FOOT 
97  100159  SCREW MACH 10-32 X 3/4 PH PN 
98  101078  ST 8-32 X 5/16 PH PN 
99  100173  MS 8-32 X 1/4 PH PN
45  46
Page 31
REPACKING INSTRUCTION
MC207
47
Page 32
POWER AMPLIFIER
SERVICE MANUAL
The continuous improvement of its products is the policy of McIntosh Laboratory Incorporated, who reserve the right to improve design without 
notice. Because of the constant upgrading of McIntosh products’ circuitry and components, the Company cannot insure, and does not warrant, the 
accuracy of the within schematic material, which is intended for information only.
McINTOSH LABORATORY, INC.,   2 CHAMBERS STREET,  BINGHAMTON,  NEW YORK  13903  Printed in U.S.A.  Part Number 040929
Page 33
Q2  TRANSISTOR PNP  132224 
Q3  TRANSISTOR NPN  132268 
Q4  TRANSISTOR PNP  132267 
Q5  TRANSISTOR NPN  132223 
Q7  TRANSISTOR PNP  132286 
Q8  TRANSISTOR PNP POWER  132299 
Q9  TRANSISTOR NPN POWER  132298 
Q1 0  TRANSISTOR PNP POWER  132299 
Q1 1  TRANSISTOR NPN POWER  132298 
Q1 2  TRANSISTOR NPN  132223 
Q1 3  TRANSISTOR PNP  132224 
Q1 4  TRANSISTOR NPN  132223 
Q1 5  TRANSISTOR PNP  132286 
Q1 6  TRANSISTOR NPN  132285 
Q1 7  TRANSISTOR PNP  132267 
Q1 8  TRANSISTOR NPN  132268 
Q1 9  TRANSISTOR NPN POWER  132298 
Q2 0  TRANSISTOR NPN POWER  132298 
Q2 1  TRANSISTOR PNP POWER  132299 
Q2 2  TRANSISTOR PNP POWER  132299 
Q2 3  TRANSISTOR NPN POWER  132298 
Q2 4  TRANSISTOR NPN POWER  132298 
Q2 5  TRANSISTOR PNP POWER  132299 
Q2 6  TRANSISTOR PNP POWER  132299 
Q2 7  TRANSISTOR PNP  132224 
Q2 8  TRANSISTOR SI NPN 25V  132254 
Q2 9  TRANSISTOR PNP POWER  132255 
Q3 0  TRANSISTOR SI NPN 25V  132254 
Q3 1  TRANSISTOR NPN  132223 
Q3 2  TRANSISTOR NPN  132223 
Q3 3  TRANSISTOR PNP POWER  132255 
Q3 4  TRANSISTOR NPN  132223 
Q3 5  TRANSISTOR NPN  132223 
Q3 6  TRANSISTOR NPN  132285 
Q3 7  TRANSISTOR NPN  132285 
Q3 8  TRANSISTOR PNP POWER  132255 
Q3 9  TRANSISTOR PNP  132286 
Q4 0  TRANSISTOR PNP  132224 
Q4 1  TRANSISTOR PNP  132224 
Q4 2  TRANSISTOR NPN  132223 
Q4 3  TRANSISTOR PNP  132224 
Q4 4  TRANSISTOR PNP POWER  132255 
Q4 5  TRANSISTOR PNP POWER  132255 
Q4 6  TRANSISTOR PNP  132224 
Q4 7  TRANSISTOR SI NPN 25V  132254 
Q4 8  TRANSISTOR PNP  132286 
Q4 9  TRANSISTOR PNP  132224 
Q5 0  TRANSISTOR NPN  132223 
Q5 1  TRANSISTOR NPN  132223 
Q5 2  TRANSISTOR NPN  132223 
Q5 3  TRANSISTOR PNP POWER  132255 
Q5 4  TRANSISTOR PNP  132224 
Q5 5  TRANSISTOR PNP POWER  132255 
Q5 6  TRANSISTOR PNP POWER  132255 
Q5 7  TRANSISTOR SI NPN 25V  132254 
Q5 8  TRANSISTOR NPN  132223 
Q5 9  TRANSISTOR NPN  132223 
Q6 0  TRANSISTOR SI NPN 25V  132254 
Q6 1  TRANSISTOR SI NPN 25V  132254 
Q6 2  TRANSISTOR PNP  132224 
Q6 3  TRANSISTOR NPN  132223 
Q6 4  TRANSISTOR PNP POWER  132255 
R1  RES MF 332 OHM 1% 1/4W  144446 
R2  RES MET OX 680 OHM 5% .5W  137093 
R3  RES MF 22.1K 1% 1/4W  144187 
R4  RES MF 100K 1% 1/4W  144113 
R5  RES MF 22.1K 1% 1/4W  144187 
R6  RES MET OX 1.8k 5% .5W  137094 
R7  RES MET OX 430 OHM 5% .5W  137095 
R8  RES MF 332 OHM 1% 1/4W  144446 
R9  RES MET OX 680 OHM 5% .5W  137093 
R1 0  RES MF 22.1K 1% 1/4W  144187 
R1 1  RES MET OX 1.8k 5% .5W  137094 
R1 2  RES MET OX 47 OHM 5% .5W  137096 
R13  POT TRIM 200 OHM 20% HORIZ AD  134390 
R1 4  RES MF 100K 1% 1/4W  144113 
R1 5  RES MF 100 OHM 1% 1/4W  144196 
R1 6  RES MF 100 OHM 1% 1/4W  144196 
R1 7  RES MF 100 OHM 1% 1/4W  144196 
R1 8  RES MET OX 47 OHM 5% .5W  137096 
R1 9  RES MET OX 1.8k 5% .5W  137094 
R2 0  RES MF 332 OHM 1% 1/4W  144446 
R2 1  RES MF 22.1K 1% 1/4W  144187 
R2 2  RES MET OX 680 OHM 5% .5W  137093 
R2 3  RES MET OX 430 OHM 5% .5W  137095 
R2 4  RES MET OX 680 OHM 5% .5W  137093 
R2 5  RES MF 22.1K 1% 1/4W  144187 
R2 6  RES MET OX 1.8k 5% .5W  137094 
R2 7  RES MF 332 OHM 1% 1/4W  144446 
R28  POT TRIM 200 OHM 20% HORIZ AD  134390 
R2 9  RES MF 475K 1% 1/4W  144364 
R3 0  RES MF 475K 1% 1/4W  144364
R3 1  RES MF 5.11K 1% 1/4W  144083 
R3 2  RES MF 47.5K 1% 1/4W  144108 
R3 3  RES MF 47.5K 1% 1/4W  144108 
R3 4  RES MF 5.11K 1% 1/4W  144083 
R3 5  RES MF 47.5K 1% 1/4W  144108 
R3 6  RES 511 OHM 1% 1/4W  144123 
R3 7  RES MF 681K 1% 1/4W  144443 
R3 8  RES MF 866 OHM 1% 1/4W  144028 
R3 9  RES MF 2.21 OHM 1/4W 1%  144378 
R4 0  RES WW DUAL .47 OHM 5% 3W  139244 
R4 1  RES WW DUAL .47 OHM 5% 3W  139244 
R4 2  RES WW DUAL .47 OHM 5% 3W  139244 
R4 3  RES WW DUAL .47 OHM 5% 3W  139244 
R4 4  RES WW DUAL .47 OHM 5% 3W  139244 
R4 5  RES WW DUAL .47 OHM 5% 3W  139244 
R4 6  RES MF 4.75K 1% 1/4W  144097 
R4 7  RES MF 4.75K 1% 1/4W  144097 
R4 8  RES MF 100 OHM 1% 1/4W  144196 
R4 9  RES MF 1.1K 1% 1/4W  144091 
R5 0  RES MF 14.7K 1% 1/4W  144149 
R5 1  RES MF 221 OHM 1% 1/4W  144172 
R5 2  RES MF 267K 1% 1/4W  144118 
R5 3  RES MF 221 OHM 1% 1/4W  144172 
R5 4  RES MF 3.32K 1% 1/4W  144095 
R5 5  RES MF 3.32K 1% 1/4W  144095 
R5 6  RES MF 10K 1% 1/4W  144053 
R5 7  RES MF 475K 1% 1/4W  144364 
R5 8  RES MF 1.1K 1% 1/4W  144091 
R5 9  RES MF 2.21 OHM 1/4W 1%  144378 
R6 0  RES FP 22 OHM 1/4W 5%  137033 
R6 1  RES MF 100 OHM 1% 1/4W  144196 
R6 2  RES MF 22.1K 1% 1/4W  144187 
R6 3  RES FP 22 OHM 1/4W 5%  137033 
R6 4  RES MF 10K 1% 1/4W  144053 
R6 5  RES MF 681K 1% 1/4W  144443 
R6 6  RES MF 681K 1% 1/4W  144443 
R6 7  RES MF 100 OHM 1% 1/4W  144196 
R6 8  RES MF 475K 1% 1/4W  144364 
R6 9  RES MF 22.1K 1% 1/4W  144187 
R7 0  RES MF 100 OHM 1% 1/4W  144196 
R7 1  RES MF 100 OHM 1% 1/4W  144196 
R7 2  RES MF 100 OHM 1% 1/4W  144196 
R7 3  RES MF 100 OHM 1% 1/4W  144196 
R7 4  RES MF 100 OHM 1% 1/4W  144196 
R7 5  RES MF 267K 1% 1/4W  144118 
R7 6  RES MF 221 OHM 1% 1/4W  144172 
R7 7  RES MF 1M 1/4W  144269 
R7 8  RES MF 100 OHM 1% 1/4W  144196 
R7 9  RES CF 10 OHM 5% 1/2W  141165 
R8 0  RES CF 10 OHM 5% 1/2W  141165 
R8 1  RES MF 100 OHM 1% 1/4W  144196 
R8 2  RES MF 1M 1/4W  144269 
R8 3  RES MF 10K 1% 1/4W  144053 
R8 4  RES MF 47.5K 1% 1/4W  144108 
R8 5  RES MF 1.1K 1% 1/4W  144091 
R8 6  RES MF 4.75K 1% 1/4W  144097 
R8 7  RES MF 14.7K 1% 1/4W  144149 
R8 8  RES MF 12.1K 1% 1/4W  144154 
R8 9  RES MF 953 OHM 1/4W 1%  144473 
R9 0  RES MF 1.1K 1% 1/4W  144091 
R9 1  RES MF 681K 1% 1/4W  144443 
R9 2  RES MF 866 OHM 1% 1/4W  144028 
R9 3  RES MF 4.75K 1% 1/4W  144097 
R9 4  RES MF 47.5K 1% 1/4W  144108 
R9 5  RES MF 1.1K 1% 1/4W  144091 
R9 6  RES MF 3.32K 1% 1/4W  144095 
R9 7  RES 511 OHM 1% 1/4W  144123 
R9 8  RES MF 3.32K 1% 1/4W  144095 
R9 9  RES MF 221 OHM 1% 1/4W  144172 
R100 RES MF 1.1K 1% 1/4W  144091 
R101 RES MF 953 OHM 1/4W 1%  144473 
R102 RES MF 332K 1% 1/4W  144119 
R103 RES MF 332K 1% 1/4W  144119 
R104 RES MF 15K 1% 1/4W  144412 
R105 RES MF 6.49K 1% 1/4W  144140 
R106 RES MF 475 OHM 1% 1/4W  144086 
R107 RES MF 475 OHM 1% 1/4W  144086 
R108 RES MF 6.49K 1% 1/4W  144140 
R109 RES CF 0 OHM 5% 1/4W  141389 
R110 RES MET OX 430 OHM 5% .5W  137095 
R111 RES MET OX 430 OHM 5% .5W  137095 
R112 RES MF 1M 1/4W  144269 
R113 RES CF 10 OHM 5% 1/2W  141165 
R114 RES CF 10 OHM 5% 1/2W  141165 
R115 RES MF 1M 1/4W  144269 
R119 RES MO 4.7 OHM 1W 5%  144464 
R120 RES MO 4.7 OHM 1W 5%  144464 
R122 RES MF 47.5K 1% 1/4W  144108 
R123 RES MF 22.1K 1% 1/4W  144187 
R124 RES MF 47.5K 1% 1/4W  144108 
RT 1  SENSOR THERMAL  144249 
RT 2  SENSOR THERMAL  144249
POWER AMPLIFIER
SERVICE MANUAL ADDENDUM
A
3
B
HEATSINK 1-CHANNEL
* Denotes components on reverse or backside of PC Board. 
MCINTOSH LABORATORY, INC.,   2 CHAMBERS STREET,  BINGHAMTON,  NEW YORK  13903  Printed in U.S.A.
050070 HEATSINK ASSEMBLY 050187
MC207.SMA01.040929 090204
Page 34
A 
B
4
C
HEATSINK 2-CHANNEL
* Denotes components on reverse or backside of PC Board. 
P AR TS LIST
Ref No.  Description
3A
050070 HEATSINK 1-CHANNEL PCB
C1  CAP ELECT 47UF 35V  066446
3B
C2  CAP ELECT 47UF 35V  066446 
C3  CAP MONO .1uF 50V 20% Z5U  061305 
C4  CAP POLYPROP 0.15UF 10% 250VDC  064363 
C7  CAP MONO 100PF 100V 10% NPO  061300 
C8  CAP MONO 100PF 100V 10% NPO  061300 
C9  CAP MONO .01UF 50V 20% X7R  061304 
C14  CAP MONO 100PF 100V 10% NPO  061300 
C1 6  CAP MONO .01UF 50V 20% X7R  061304 
C22  CAP ELECT 220UF 25V  066507 
C27  CAP MONO 100PF 100V 10% NPO  061300 
C30  CAP ELECT 47UF 35V  066446 
C31  CAP ELECT .47UF 50V  066244 
C3 2  CAP MONO .1uF 50V 20% Z5U  061305 
C3 3  CAP MONO .1uF 50V 20% Z5U  061305 
C35  CAP ELECT 10UF 100VDC  066462 
C36  CAP ELECT 10UF 100VDC  066462 
C37  CAP ELECT 10UF 100VDC  066462
Part No
LD1  LDR NETWORK  144179 
Q1  TRANSISTOR NPN  132223
050064 HEATSINK ASSEMBLY 050188
C38  CAP ELECT 10UF 100VDC  066462 
C40  CAP ELECT 220UF 50V 20%  066254
.
C41  CAP ELECT 10UF 100VDC  066462 
C47  CAP POLYPROP .047UF 10% 250VDC  064364 
C51  CAP ELECT 10UF 100VDC  066462 
C200 CAP ELECT 10UF 100VDC  066462 
D1  DIODE SILICON  070047 
D2  DIODE SILICON  070047 
D4  DIODE SILICON  070047 
D5  DIODE SILICON  070047 
D6  DIODE RECTIFIER  070131 
D7  DIODE RECTIFIER  070131 
IC2  IC DUAL AMP  133259 
J1  CONN MALE 9 POS FRICTION LOCK  117244 
J2  CONN 4 PIN  117215 
J4  CONN HEADER 2 PIN 0.156  117404 
J5  BLADE FASTON .110  117712 
J6  BLADE FASTON W/FEET  117708 
J8  CONN HEADER 2 PIN 0.156  117404 
J9  CONN 2 PIN MALE  117213 
K1  RELAY 24VDC 5A 277VAC  087057 
K2  RELAY 24VDC 5A 277VAC  087057 
L2  CHOKE 0.65UH OUTPUT  122297
2
Q2  TRANSISTOR PNP  132224 
Q3  TRANSISTOR NPN  132268 
Q4  TRANSISTOR PNP  132267 
Q5  TRANSISTOR NPN  132223 
Q6  TRANSISTOR NPN  132285 
Q7  TRANSISTOR PNP  132286 
Q8  TRANSISTOR PNP POWER  132299 
Q9  TRANSISTOR NPN POWER  132298 
Q1 0  TRANSISTOR PNP POWER  132299 
Q1 1  TRANSISTOR NPN POWER  132298 
Q2 0  TRANSISTOR NPN POWER  132298 
Q2 2  TRANSISTOR PNP POWER  132299 
Q2 3  TRANSISTOR NPN POWER  132298 
Q2 5  TRANSISTOR PNP POWER  132299 
Q2 7  TRANSISTOR PNP  132224 
Q2 9  TRANSISTOR PNP POWER  132255 
Q3 0  TRANSISTOR SI NPN 25V  132254 
Q3 1  TRANSISTOR NPN  132223 
Q3 2  TRANSISTOR NPN  132223 
Q3 3  TRANSISTOR PNP POWER  132255 
Q3 5  TRANSISTOR NPN  132223 
Q3 7  TRANSISTOR NPN  132285 
Q3 9  TRANSISTOR PNP  132286 
Q4 1  TRANSISTOR PNP  132224 
Q4 9  TRANSISTOR PNP  132224 
Q5 0  TRANSISTOR NPN  132223 
Q5 1  TRANSISTOR NPN  132223 
Q5 2  TRANSISTOR NPN  132223 
Q5 3  TRANSISTOR PNP POWER  132255 
Q5 4  TRANSISTOR PNP  132224 
Q5 5  TRANSISTOR PNP POWER  132255 
Q5 6  TRANSISTOR PNP POWER  132255 
Q5 9  TRANSISTOR NPN  132223 
Q6 0  TRANSISTOR SI NPN 25V  132254 
Q6 1  TRANSISTOR SI NPN 25V  132254 
Q6 3  TRANSISTOR NPN  132223 
Q6 4  TRANSISTOR PNP POWER  132255 
R1  RES MF 332 OHM 1% 1/4W  144446 
R2  RES MET OX 680 OHM 5% .5W  137093 
R3  RES MF 22.1K 1% 1/4W  144187 
R4  RES MF 100K 1% 1/4W  144113 
R5  RES MF 22.1K 1% 1/4W  144187 
R6  RES MET OX 1.8k 5% .5W  137094 
R7  RES MET OX 430 OHM 5% .5W  137095 
R8  RES MF 332 OHM 1% 1/4W  144446 
R9  RES MET OX 680 OHM 5% .5W  137093 
R1 0  RES MF 22.1K 1% 1/4W  144187 
R1 1  RES MET OX 1.8k 5% .5W  137094 
R1 2  RES MET OX 47 OHM 5% .5W  137096 
R13  POT TRIM 200 OHM 20% HORIZ AD  134390 
R1 4  RES MF 100K 1% 1/4W  144113 
R1 5  RES MF 100 OHM 1% 1/4W  144196 
R1 6  RES MF 100 OHM 1% 1/4W  144196 
R1 7  RES MF 100 OHM 1% 1/4W  144196 
R3 0  RES MF 475K 1% 1/4W  144364 
R3 2  RES MF 47.5K 1% 1/4W  144108 
R3 3  RES MF 47.5K 1% 1/4W  144108 
R3 4  RES MF 5.11K 1% 1/4W  144083 
R3 6  RES 511 OHM 1% 1/4W  144123 
R3 7  RES MF 681K 1% 1/4W  144443 
R3 8  RES MF 866 OHM 1% 1/4W  144028 
R3 9  RES MF 2.21 OHM 1/4W 1%  144378 
R4 1  RES WW DUAL .47 OHM 5% 3W  139244 
R4 2  RES WW DUAL .47 OHM 5% 3W  139244 
R4 3  RES WW DUAL .47 OHM 5% 3W  139244 
R4 5  RES WW DUAL .47 OHM 5% 3W  139244 
R4 6  RES MF 4.75K 1% 1/4W  144097 
R4 8  RES MF 100 OHM 1% 1/4W  144196 
R5 0  RES MF 14.7K 1% 1/4W  144149 
R5 1  RES MF 221 OHM 1% 1/4W  144172 
R5 2  RES MF 267K 1% 1/4W  144118 
R5 3  RES MF 221 OHM 1% 1/4W  144172 
R5 4  RES MF 3.32K 1% 1/4W  144095 
R5 5  RES MF 3.32K 1% 1/4W  144095 
R5 6  RES MF 10K 1% 1/4W  144053 
R5 7  RES MF 475K 1% 1/4W  144364 
R5 8  RES MF 1.1K 1% 1/4W  144091 
R5 9  RES MF 2.21 OHM 1/4W 1%  144378 
R6 0  RES FP 22 OHM 1/4W 5%  137033 
R6 2  RES MF 22.1K 1% 1/4W  144187 
R6 3  RES FP 22 OHM 1/4W 5%  137033 
R6 5  RES MF 681K 1% 1/4W  144443 
R6 7  RES MF 100 OHM 1% 1/4W  144196 
R7 0  RES MF 100 OHM 1% 1/4W  144196 
R7 1  RES MF 100 OHM 1% 1/4W  144196 
R7 2  RES MF 100 OHM 1% 1/4W  144196 
R7 7  RES MF 1M 1/4W  144269 
R7 9  RES CF 10 OHM 5% 1/2W  141165 
R8 2  RES MF 1M 1/4W  144269
3
R8 3  RES MF 10K 1% 1/4W  144053 
R8 4  RES MF 47.5K 1% 1/4W  144108 
R8 5  RES MF 1.1K 1% 1/4W  144091 
R8 6  RES MF 4.75K 1% 1/4W  144097 
R8 8  RES MF 12.1K 1% 1/4W  144154 
R9 0  RES MF 1.1K 1% 1/4W  144091 
R9 3  RES MF 4.75K 1% 1/4W  144097 
R101 RES MF 953 OHM 1/4W 1%  144473 
R103 RES MF 332K 1% 1/4W  144119 
R104 RES MF 15K 1% 1/4W  144412 
R105 RES MF 6.49K 1% 1/4W  144140 
R106 RES MF 475 OHM 1% 1/4W  144086 
R109 RES CF 0 OHM 5% 1/4W  141389 
R111 RES MET OX 430 OHM 5% .5W  137095 
R114 RES CF 10 OHM 5% 1/2W  141165 
R119 RES MO 4.7 OHM 1W 5%  144464 
R122 RES MF 47.5K 1% 1/4W  144108 
R123 RES MF 22.1K 1% 1/4W  144187 
R124 RES MF 47.5K 1% 1/4W  144108 
RT1  SENSOR THERMAL  144249 
RT2  SENSOR THERMAL  144249
4A 
4B
050064 HEATSINK 2-CHANNEL PCB
C1  CAP ELECT 47UF 35V  066446
4B
C2  CAP ELECT 47UF 35V  066446 
C3  CAP MONO .1uF 50V 20% Z5U  061305 
C4  CAP POLYPROP 0.15UF 10% 250VDC  064363 
C7  CAP MONO 100PF 100V 10% NPO  061300 
C8  CAP MONO 100PF 100V 10% NPO  061300 
C9  CAP MONO .01UF 50V 20% X7R  061304 
C10  CAP ELECT 47UF 35V  066446 
C11  CAP ELECT 47UF 35V  066446 
C12  CAP MONO 100PF 100V 10% NPO  061300 
C13  CAP MONO 100PF 100V 10% NPO  061300 
C14  CAP MONO 100PF 100V 10% NPO  061300 
C1 5  CAP MONO .1uF 50V 20% Z5U  061305 
C1 6  CAP MONO .01UF 50V 20% X7R  061304 
C1 7  CAP MONO .01UF 50V 20% X7R  061304 
C1 8  CAP MONO .01UF 50V 20% X7R  061304 
C19  CAP MONO 100PF 100V 10% NPO  061300 
C22  CAP ELECT 220UF 25V  066507 
C27  CAP MONO 100PF 100V 10% NPO  061300 
C28  CAP MONO 100PF 100V 10% NPO  061300 
C29  CAP ELECT 47UF 35V  066446 
C30  CAP ELECT 47UF 35V  066446 
C31  CAP ELECT .47UF 50V  066244 
C3 2  CAP MONO .1uF 50V 20% Z5U  061305 
C3 3  CAP MONO .1uF 50V 20% Z5U  061305 
C35  CAP ELECT 10UF 100VDC  066462 
C36  CAP ELECT 10UF 100VDC  066462 
C37  CAP ELECT 10UF 100VDC  066462 
C38  CAP ELECT 10UF 100VDC  066462 
C39  CAP ELECT .47UF 50V  066244 
C40  CAP ELECT 220UF 50V 20%  066254 
C41  CAP ELECT 10UF 100VDC  066462 
C44  CAP ELECT 220UF 25V  066507 
C47  CAP POLYPROP .047UF 10% 250VDC  064364 
C48  CAP POLYPROP .047UF 10% 250VDC  064364 
C50  CAP ELECT 10UF 100VDC  066462 
C51  CAP ELECT 10UF 100VDC  066462 
C200 CAP ELECT 10UF 100VDC  066462 
D1  DIODE SILICON  070047 
D2  DIODE SILICON  070047 
D4  DIODE SILICON  070047 
D5  DIODE SILICON  070047 
D6  DIODE RECTIFIER  070131 
D7  DIODE RECTIFIER  070131 
D8  DIODE SILICON  070047 
D9  DIODE SILICON  070047 
D1 1  DIODE SILICON  070047 
D1 2  DIODE SILICON  070047 
D1 3  DIODE RECTIFIER  070131 
D1 4  DIODE RECTIFIER  070131 
IC1  IC DUAL AMP  133259 
IC2  IC DUAL AMP  133259 
J1  CONN MALE 9 POS FRICTION LOCK  117244 
J2  CONN 4 PIN  117215 
J3  CONN HEADER 2 PIN 0.156  117404 
J4  CONN HEADER 2 PIN 0.156  117404 
J5  BLADE FASTON .110  117712 
J6  BLADE FASTON W/FEET  117708 
J8  CONN HEADER 2 PIN 0.156  117404 
J9  CONN 2 PIN MALE  117213 
J1 0  CONN 2 PIN MALE  117213 
K1  RELAY 24VDC 5A 277VAC  087057 
K2  RELAY 24VDC 5A 277VAC  087057 
L1  CHOKE 0.65UH OUTPUT  122297 
L2  CHOKE 0.65UH OUTPUT  122297 
LD1  LDR NETWORK  144179 
LD2  LDR NETWORK  144179 
Q1  TRANSISTOR NPN  132223