SPECIFICATIONS
Useable Sensitivity
2.5 microvolts at 100% modulation (±75KC
deviation) for less than 3% total noise and
harmonic distortion in accordance with
IHF standards.
Audio Frequency Response
Within ½db from 20 to 20,000 cycles.
Distortion
Lessthan0.5%at 100% modulation ±75KC
deviation
Capture Ratio
1.5db at 100% modulation.
Muting
IF injected ultrasonic muting: at least 60db
noise reduction between stations.
Oscillator Drift
Less than 25KC with AFC disabled; negli-
gible with AFC in operation.
Image Rejection
Better than 80db at 90MC; better than
70db at 105MC.
Hum
Better than 70db below 100% modulation.
Output
Approximately 2.5 volts; low impedance.
Antenna Inputs
300 ohms balanced; 75 ohms unbalanced.
RF Amplifier
Cascode with 6DS4 Nuvistor in first stage.
IF Stages
Five, with 200KC bandwidth, flat top
response.
Limiters
Two.
Radiation
Substantially below FCC requirements.
Multiplex Channel Separation
Better than 30db at 1000 cycles.
Multiplex Filter
Greater than 48db suppression of 19KC
pilot and 38KC carrier.
Multiplex Indicator
Front panel multiplex stereo light activated
by 19KC carrier-only.
Multiplex Type
Peak-detecting, self matrixing detector.
SCA Filter
50db down at 67KC to 74KC 275db per
octave slope.
Automatic Mono-Stereo Switch
An exclusive Mclntosh development; all-
electronic automatic mono-stereo switch-
ing circuit. (Pat. Pend.).
Tube and Semiconductor Complement
1-6DS4 Nuvistor, 1st RF.
1-12AT7, 2nd RF and Mixer.
1-6BN4A, Oscillator.
1-6AU6, 1st IF.
1-6AU6, 2nd IF.
1-6AU6, 3rd IF.
1-6AU6, 4th IF and 1st Limiter.
1-6CS6, 5th IF 2nd Limiter and Muting.
1—6BN8, Muting Amplifier, Muting
Detector, AVC Clamper.
2-6BL8, Left and Right, 1st and 2nd
Audio Amplifiers.
1-6U8, MPX Amplifier, MPX Indicator
Control.
1-6HU6/EM87 Multipath Indicator.
1-12AU7, MPX Oscillator.
1-ST2-275, Voltage Reference.
1-MA113 (Transistor), MPX Indicator
Lamp Switch.
2-1N542 Diodes, Wide Band
Discriminator.
2—1N542 Diodes, Narrow Band
Discriminator.
4-1N542 Diodes, Balanced MPX
Detector.
2-1N542 Diodes, Balanced Detector for
MPX Indicator.
2—Selenium Rectifiers, High Voltage
Power Supply.
1-No. 1850 Lamp, MPX Indicator.
Power Consumption
70 watts, 105 to 125 volts, 50 to 60 cycles.
Dimensions
Front Panel; 16 inches wide by 5
7
/
16
inches
high; chassis (including PANLOC shelf) 15
inches wide by 5 inches high by 13 inches
deep, including connectors; clearance in
front of mounting panel including knobs.
1½ inches.
Weight
Chassis only, 27 pounds.
In shipping carton, 37 pounds.
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