4.2 Volts Balanced 240V ~ 50/60Hz at 6 Amps 2.1 Volts Unbalanced Standby: less than 0.5 watt Note: Refer to the rear panel of the MC452 for the correct Signal To Noise Ratio (A-Weighted) voltage. 95dB Balanced (122dB below rated output)
BLOCK DIAGRAM POSITIVE CURRENT LIMITER POWER DIFF VOLTAGE CURRENT INDICATOR PREDRIVER DRIVER TRANSDUCER GUARD OUTPUT CURRENT ThermalTrak CURRENT SOURCE DC BIAS UNBALANCED VOLTAGE DIFF INPUT PREDRIVER DRIVER OUTPUT RECTIFIER METER UNBALANCED OUTPUT THERMAL LEFT NEGATIVE VOLTAGE SENSORS METER OUTPUT CURRENT HOLD SWITCH LIMITER...
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MC452 INTERCONNECT MC452 TRANSFORMER WIRING AND FUSE REPLACEMENT (CONTACT MCINTOSH FOR CURRECT TRANSFORMER P/N) Voltage BLK BLK/GRY GRY VIO WHT/VIO BRN 1 BRN 2 Jumper Location (JMP1) Main Fuse (F1) T15AH250V T15AH250V T15AH250V WHT 24 AWG WHT 18 AWG TERMINAL...
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MAIN 751311 SCH 1 of 3 +15V PC OUTPUT +15V +15V DRIVER 13.2V MODE MODE J26:1 MUTE J21:5 MUTE -18V +15V J26:5 +15V L PG LT J21:1 -15V J26:7 -15V +15V J21:3 +15V PC OUT J26:3 PC OUTPUT PC OUT DELAY -15V J21:4...
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MC452 MAIN 751311 SCH 2 of 3 +14VML U8:1 33.2k -5VML 1000pF L M ETER DRIVER -5VML +14VML +14VML U8:2 1000µF FUNC 1 J29:1 18.2k FUNC 2 U10:2 FUNC 1 J29:2 FUNC 2 L METER LOG AMP +15V +14VML 200k...
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MAIN 751311 SCH 3 of 3 J1:1 J1:4 PRIMARY J1:7 J1:10 J2:10 J2:1 J2:4 J3:2 TEST ONLY ON/OFF NO CONNECTION APPLY 12VDC TO ENERGIZE RELAYS W ITH NO AC POWER J3:1 47.5K T° AC F AC DET PWR RLY AC DETECTOR REFER TO +15V CONNECTION...
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HEATSINK 751313 SCH 1 of 2 +V AMP 47 .5 W DIFFERENTIAL VOLTAGE J1:4 100µF PG ATT J1:5 PG ATT FB COM J1:1 FB COM DRV + 1.8V J1:3 2.21M -18V 2.21M AMP MUTING CURRENT SOURCE FB 8 J2:3 J2:5 FEEDBACK NETW ORK FB 2 J2:1...
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MC452 HEATSINK 751313 SCH 2 of 2 +V AMP 1.8V DRV + DRIVER 1.2V Q28:1 CURRENT Q30:1 OUTPUTS LIM ITER 1.8K Q32:1 Q34:1 BIAS ADJUSTMENT ADJUST R52 FOR 21-25 mV DC ACROSS J5 WITH NO INPUT SIGNAL AND HEATSINKS COOL...
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MC452 LEFT TERMINAL 751138 SCH LEFT OUTPUTS J8:6 L (+) L + FB8 FB 8 J8:7 J8:5 L (+) L + FB2 FB 2 J8:2 L (-) L - FB8 FB 8 J8:3 J8:1 L (-) L - FB2 FB 2...
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MC452 RIGHT TERMINAL 751222 SCH BREAKAWAY J8:6 R (+) R + FB8 FB 8 J8:7 J8:5 R (+) R + FB2 FB 2 R (-) J8:2 R - FB8 FB 8 J8:3 J8:1 R (-) R - FB2 FB 2...
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MC452 DISPLAY/METER LIGHT 751139 SCH J5:1 J7:8 POWER J5:3 J7:10 J5:5 J7:12 FP OFF J1:7 FP OFF DISPLAY FP ON J1:4 FP ON J1:1 R INTENSITY R COLOR J5:2 J7:7 J5:4 J7:9 R BLU R BLU J5:6 J7:11 R GRN...
DIODE SMALL SIGNAL 4148 SMD 070199 ASSY AUTOFORMER POTTED 751170 DIODE SMALL SIGNAL 4148 SMD 070199 CONTACT McINTOSH SERVICE DEPT DIODE SMALL SIGNAL 4148 SMD 070199 DIODE SMALL SIGNAL 4148 SMD 070199 MAIN PCB 751311 DIODE SMALL SIGNAL 4148 SMD 070199 CAP POLY 0.15UF 275VDC UL/CSA...
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PARTS LIST (Cont’d.) MAIN PCB 751311 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. TRANSISTOR N JFET 132319 DIODE SMALL SIGNAL 4148 SMD 070199 TRANSISTOR NPN 20V MUTE 2SC4694 132336 DIODE SMALL SIGNAL 4148 SMD 070199 TRANSISTOR NPN 20V MUTE 2SC4694 132336 DIODE SMALL SIGNAL 4148 SMD 070199...
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MC452 PARTS LIST (Cont’d.) MAIN PCB 751311 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. RES MF 100 OHM 1% 1/4W 144568 BLADE FASTON W/FEET 117708 BLADE FASTON W/FEET 117708 RES MF 475K 1% 1/4W 144604 BLADE FASTON W/FEET 117708 RES MF 12.1K 1% 1/4W...
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PARTS LIST (Cont’d.) RIGHT IMPUT PCB 751221 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. CAP 47PF 200V 10% NPO SMD0805 061368 CAP .01UF 50V 20% NPO SMD0805 061372 CAP MONO .1UF 50V + _ 20% X7R SMD0805 061365 CAP MONO .1UF 50V ±20% X7R SMD 061365 CAP ELECT 10UF 50V...
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MC452 PARTS LIST (Cont’d.) HEATSINK ASSY 751313 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. (Q28) HEATSINK 018614 RES SMD0805 681K 1/8W 1% 145041 (Q28) ISOSTRATE 084206 RES SMD0805 2.21M 1/8W 1% 145043 (Q28) CLIP TRANSISTOR 214...
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PARTS LIST (Cont’d.) LEFT TERMINAL PCB 751138 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. CAP POLYPROP 0.047UF 10% 275V 064466 DS16 LED RGB SMD 058196 CAP POLYPROP 0.047UF 10% 275V 064466 DS17 LED RGB SMD 058196 BLADE FASTON W/FEET 117708 DS18...
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MC452 PARTS LIST (Cont’d.) DISPLAY/METER LIGHT PCB 751139 (Cont’d.) Ref. No. Description Part No. Ref. No. Description Part No. RES SMD0805 3.92K 1/8W 1% 145027 RES SMD0805 1.5K 1/8W 1% 145007 RES SMD0805 3.92K 1/8W 1% 145027 RES SMD0805 1.5K 1/8W 1% 145007 RES SMD0805 3.92K 1/8W 1%...
If a shipping carton or any of the interior 401212 1/4 - 20x2-1/4 cap screw part(s) are needed, please call or write Customer 104058 Flat washer Service Department of McIntosh Laboratory. Refer to page 3. Please see the Part List for the correct part numbers.
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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.
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