McIntosh 1200 Operating and installation instructions

STEREOTECH
AM/FM RECEIVER
SERVICE
INFORMATION
SERIAL NUMBER BKIOOI AND ABOVE

1200
PERFORMANCE DETAILS
PREAMPLIFIER AND POWER AMPLIFIER
POWER OUTPUT
50 watts minimum sine wave
continuous average power out¬
put, per channel, both channels
operating into 8 ohms load im¬
pedance.
30 watts minimum sine wave
continuous average power out¬
put, per channel, both channels
operating into 16 ohms load im¬
pedance.
OUTPUT LOAD IMPEDANCE
8 ohms or 16 ohms
RATED POWER BAND
20 Hz to 20,000 Hz
TOTAL HARMONIC DISTORTION
0.2% maximum harmonic distor¬
tion at any power level from 250
milliwatts to rated power per
channel across 8 ohms or 16
ohms; both channels operating.
INTERMODULATION DISTORTION
0.2% if instantaneous peak power output is twice
rated power or less per channel with both channels
operating for any combination of frequencies 20 Hz
to 20,000 Hz
FREQUENCY RESPONSE
20 Hz to 20,000 ±1 dB
NOISE AND HUM
Power Amplifier: 95 dB below rated output
Tape 1 and Tape 2, Aux 1 and Aux 2: 89 dB below
rated output
Phono 1 and Phono 2: 70 dB below 10 mV input
RATINGS
DAMPING FACTOR
48 at 8 ohms output
96 at 16 ohms output
INPUT SENSITIVITY AND IMPEDANCE
Power Amplifier: 1.2 volts, 40,000 ohms
Phono 1 and Phono 2: 3.0 mV, 47,000 ohms
Tape 1 and Tape 2: 350 mV, 100,000 ohms
Aux 1 and Aux 2: 350 mV, 100,000 ohms
TAPE OUTPUT
Preamp: 12 volts with rated input
Tuner: 1.2 volts at 100% FM modulation
Tape: 350 mV with rated input from low level inputs
Phono: 1.2 volts with 10 mV input at 1000 Hz
TONE CONTROLS: Bass +16 dB at 20 Hz. Treble
+ 16 dB at 20,000 Hz.
L.F. FILTER: Active filter with 12 dB per octave
roll off below 50 Hz, down 18 dB at 20 Hz.
H.F. FILTER: Active filter with 12 dB per octave
roll off above 7000 Hz, down 18 dB at 20,000 Hz.
AM TUNER
TUNING RANGE: 535 to 1605 kHz.
SENSITIVITY: 75 juV IHF (external ant.)
SIGNAL TO NOISE RATIO: 50 dB minimum
(IHF,) 60 dB at 100% modulation.
HARMONIC DISTORTION: Less than 1% (IHF.)
IMAGE REJECTION: Greater than 60 dB 535 to
1605 kHz.
FM TUNER
TUNING RANGE: 87.5 to 108.5 MHz.
USEABLE SENSITIVITY: 2.5 microvolts at 100%
modulation (+75 kHz deviation) for 3% total noise
and harmonic distortion (IHF).
SIGNAL TO NOISE RATIO: 70 dB below 100%
modulation.
HARMONIC DISTORTION: Less than 0.5% mono
and less than 0.7% stereo.
AUDIO FREQUENCY RESPONSE: +1 dB 50 Hz
to 10,000 Hz, ±2 dB 20 Hz to 15,000 Hz.
SELECTIVITY: 55 dB alternate channel minimum
(IHF)
SPURIOUS REJECTION: 90 dB minimum (IHF)
IMAGE REJECTION: 70 dB minimum
STEREO SEPARATION: 35 dB minimum at 1,000
Hz.
SCA FILTER: 60 dB minimum
GENERAL INFORMATION
POWER REQUIREMENTS: 120 volts 50-60 Hz 50
watts at zero input, 320 watts rated output.
SEMICONDUCTOR COMPLEMENT: 68 Transis¬
tors; 4 FETs, 5 ICs, 39 Diodes.
MECHANICAL INFORMATION
SIZE: Front panel measures 17-1/2 inches wide (444
mm), by 5-5/32 inches high (131 mm). Chassis meas¬
ures 16-15/16 inches wide (430 mm), by 4-5/8 inches
high (117 mm), by 15-7/8 inches deep (403 mm) plus
antenna. Knob clearance required is 1-1/2 inches
(31 mm) in front of the mounting panel.
WEIGHT: 33 pounds (14.97 kg) net, 39 pounds
(17.69 kg) in shipping cartons.

LOUDNESS
TONE AMP
NEG FEEDBACK I
TONE CONTROL \
NEG FEEDBACK L
TONE CONTROL!
TONE AMP
DIFFERENTIAL
AMP y
POWER
CONTROLLER

i
SIGNAL
1
1_
STRENGTH
ci_
_*
RIGHT
DE-EMPHASIS
LEFT FM
TO INPUT
SELECTOR
SWITCH
RIGHT FM
TO INPUT
SELECTOR
SWITCH
BLOCK DIAGRAM

FM ANT
> RI02 <RI0l
>IM OOOK
TRIOI
2SK4IE
CI02 (2SKI9)
0.01 N.
TRI02
2SK4IE
Cl07 (2SKI9)
0.01 /TN
044458 FM TUI'
PC BOARD
Rl09 LI 03
100 --
* R105 VCIOl /
' 330 V—
* RIlO VCIOl / I TCI03 I
> 330 ii -1
C452 _L
4.7P
/
/ TCI07
<
VCIOl / TCI06
> / J*
044461
MPX/AFL
MUTING PCB
AM ANT
MAC 1200
TUNER SECTION
R4I6
470 ^ 0415
I 0.02
C405
I/50V+20%
f ,C407
. _ J 0.005
L40I
C403 C404
0.02 0.04
C408
_ 3.3/25V >
- ±20% S R40B
I_1
L402
AM-FM TUNER

1200

f—If—ll'
TO +I6V
04461
MPX/AFL
MUTING PCS
154-603

1200 1200
YELLOW

PREAMP PC BOARD 044-462
FILTER AMP PC BOARD 044-466
+
C
5
09
o

044462 PREAMP PC BOARD
TO
FM MPX PC BOARO
OUT
6r ^
044462 PREAMP PC BOARD

1200
PREAMP

MULTIPLEX

1200
J
044465
PUSHBUTTON SWITCH
PC BOARD
154-605

LEFT CHANNEL
OUT
1
RIGHT CHANNEL
OUT
-— ♦ + 40V
044465
1 PUSHBUTTON SWITCH
I PC BOARD

POWER OUTPUT PC BOARD 044-463
TR6050
GRAY
GREEN