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C 22

SERVICE INFORMATION
STARTING WITH SERIAL NO. 10A01

C 22

M c l N T O S H L A B O R A T O R Y INC.

2 CHAMBERS STREET

BINGHAMTON, NEW Y O R K

ELECTRICAL SPECIFICATIONS

Frequency Response +0.5 to -0.5 dB, 20Hz to 20,000Hz Distortion Less than 0.2% at 10 volts output Less than 0.02% at 3 volts output Input Sensitivity (phono 1, phono 2, tape head) 2 millivolts for 2.5 volts output at 1kHz Input Sensitivity (Microphone) 2.5 millivolts for 2.5 volts output Input Sensitivity (aux, tape, tuner) 0.25 volts for 2.5 volts output Hum And Noise (phono 1, phono 2, tape head) 74 dB below 10 millivolts input Hum And Noise (aux, tape, tuner) 85 dB below rated output Output (main) 2.5 volts with rated input. Up to 10 volts can be developed without distortion. Output (tape) 0.25 volts with rated input. Phono input signal of 10 millivolts produces 1.25 volts output. Output (L & R) 1.0 volts with rated input on both channels. A level control adjusts output. Bass Control +20 dB at 20Hz Treble Control +20 dB at 20,000Hz LP Filter Flat or sharp cutoff below 50Hz (down 30 dB @ 20Hz). HF Filter Flat or sharp cutoff above 5000Hz (down 30 dB @ 20,000Hz).

Unless otherwise specified, resistance values are in ohms, 1/2 watt, and 10% tolerance. Capacitance values smaller than 1 are in microfarads (µF); values greater than 1 are in picofarads (pF). Resistors marked with * are 1/4W. The terminal numbering of rotary switches and printed circuit board wires is for reference only. All voltages are measured under the following conditions: 1. Use of an 11 megohm input impedance VTVM 2. All voltages ±10% with respect to ground 3. AC input at 117 volts, 50/60 cycles 4. No signal at input terminals 5. Front panel controls at normal positions

PREAMP. SECTION
154 - 318

SCHEMATIC NOTES

1. In early units C3 & 4 were 50µF. 2. C22's built before 1965 used circuit modules made by Erie Electronics. In 1965, we changed to Sprague Electric Co. The Sprague modules are electrically equivalent to the Erie modules but differ mechanically. The newer Sprague modules are used for replacement when servicing early C22 units. For data on replacing the old Erie modules with the Sprague modules, refer to Mclntosh Service Bulletin #108. In early units R76 thru R83 do not appear. In early units C35 & 36 do not appear. In early units R67 was 50 ohms.

3. 4. 5.

POWER SUPPLY
154-317

R E P L A C E M E N T PARTS
All parts not listed are common items obtainable from radio parts jobbers. Replacement parts may be obtained when ordered by PART NUMBER from: Mclntosh Laboratory Inc. Customer Service Department 2 Chambers Street Binghamton, New York 13903 (telephone 607-723-3512) CAPACITORS Symbol Number C3,4 C29 C30 C31 C32 Description Elect. Elect. Elect. Elect. Elect. 100 4µ 0F µF 3V 200V Part Number 066-047 066-049

25/200/35o/35ov
50/50/50 µF 350/350/300V 1200/1200µF 30/30V DIODES

1000/40/20 /20µF 066-037 066-033 066-029

D1,2 D3,4 D5,6

Se. rectifier Si. rectifier Si. rectifier PUSES

070-005 070-014 070-014

F1 Fuse

1 amp

089-002

CHOKES L1 ,2 Choke 100 mH . 122-004

POTENTIOMETERS R1, 2 R1, 2 R3,4 R3,4 R5 R6 R7,8,9 R7,8,9 Tape equal. (1/2 Dia. ) Tape equal. (5/8 Dia. Bass trim Bass trim (1/2 Dia. ) (5/8 Dia.) ) 134-059 134-186 134-059 134-186 134--061 134-060 134-186 134--059

Balance control Volume control Output level (5/8 Dia.) Output level (1/2 Dia. ) RESISTORS

R16,17 R20,21 R46,147 R67 R74,75

Low noise 330K Low noise 1.8K Low noise 330K Wirewound

5% 5% 5%

1W 144-005 1/2W 144-002 1W 144-005

Wirewound 33 ohm 10% 5W 139-007 7.5 ohm 10% 5W 139-010

·

SWITCHES
S1 S2

MOUNTING SYSTEM

Tape jacks switch Input selector switch Tape switch Comp. switch Mode selector switch Treble control switch Loudness switch Bass control switch Rumble switch H.F. filter switch Power switch Pilot lamp switch Phase switch TRANSFORMERS .

146-053
146-049 148-006 148-006 149-108

Shelf bracket (right) Shelf bracket (left) Mounting template #100 Hardware package MISCELLANEOUS ITEMS

043-592 043-593 038-179 043-448

S3
S4

S5 S6,7 S8

146-052 Line cord 148-006 Fuse holder 146-051 Shipping carton 148-006 Owners manual 148-006 Plastic feet 017-041 127-001 016-036 170-015 170-016 148-005 Shorting plug 148-003 Indicator glass 148-007 Audio cable (6') Audio cable (1 phone, 1 phono) 159-019 038-027 033-027 178-001 170-021

S9,10 S11
S12 S13 S14 S15

T1

Power transformer MODULES Treble cut Treble boost Bass, upper Bass, lower Rumble filter H.P. filter Phono equalization LAMPS #334 (indicator) Festoon (indicator glass) FRONT PANEL & TRIM Front panel Front panel glass End cap, right End cap, left Volume control knob Mode selector knob

130-016 130-017 130-018 130-019 130-020 130-021 130-026

058-003 058-033

043-359 016-034 018-043 018-044 043-253 043-253 043-253 043-253 O43-428 043-428 043-428 090-007 090-010 20C0425S6-8M270

- - -

Input selector knob Balance knob Bass control knob Tape jacks knob Treble control knob Rocker switch knob Level set knob

SCHEMATIC PART NO.

038-270

Be122002