marantz 2238 owners manual

The Marantz 2238 is a classic stereo receiver from the 1970s featuring 38 watts per channel, high-quality audio performance, and the distinctive Marantz blue dial illumination. This receiver includes AM/FM tuner, phono input for turntables, auxiliary inputs, tape monitor, loudness control, and tone adjustments. Below are key sections for features, installation, operation, specifications, and maintenance.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Components 7. Tuner Operation 8. Audio Adjustments 9. Care & Maintenance 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Power amplifier, AM/FM stereo tuner, Phono preamp, Input selector, Tone controls, Headphone jack.

Feature	Description
Power output	38 watts per channel into 8 ohms
Tuner section	AM/FM stereo with tuning meter
Phono input	For turntable connection (MM cartridge)
Auxiliary input	For tape deck, CD player, or other sources
Tape monitor	Tape input/output with monitor switch
Loudness control	Compensates for low volume listening
Tone controls	Bass and treble adjustments
Headphone jack	For private listening
Speaker selector	A/B speaker outputs
Power switch	Turns receiver on/off

Installation

Unpack and inspect contents. Place on stable, well-ventilated surface.

Connect speakers: Use speaker wire to connect to A or B speaker terminals.
Connect turntable: Use phono input for magnetic cartridge turntables.
Connect auxiliary sources: Use AUX input for CD players, tape decks, etc.
Connect antenna: FM antenna to FM terminals, AM antenna to AM terminals.
Plug into AC power outlet.

WARNING! Ensure proper ventilation; do not block ventilation openings. Use correct speaker impedance.

First-Time Setup

Power on receiver; allow warm-up time for optimal performance.

Select input source: Turn INPUT SELECTOR to desired source (Phono, Aux, Tuner).
Adjust volume: Start with volume at minimum, gradually increase.
Tune FM stations: Use TUNING knob and signal strength meter for best reception.
Set tone controls: Adjust bass and treble to personal preference.
Engage loudness: Use LOUDNESS switch for enhanced bass at low volumes.

CAUTION! Always turn volume down before switching inputs or powering off.

Specifications

Power Output: 38 watts per channel (8 ohms, 20Hz-20kHz)
Total Harmonic Distortion: 0.3% at rated power
Frequency Response: 10Hz-50kHz (+1, -3dB)
Input Sensitivity: Phono: 2.5mV, Aux: 250mV
Signal-to-Noise Ratio: Phono: 70dB, Aux: 85dB
Tuner Section: FM sensitivity: 2.0μV
Tone Controls: Bass: ±10dB at 50Hz, Treble: ±10dB at 15kHz
Power Requirements: 120V AC, 60Hz, 180 watts
Dimensions: 17-1/4" W × 5-1/4" H × 14-1/2" D
Weight: 22 lbs

Controls and Settings

Front panel controls: POWER, INPUT SELECTOR, VOLUME, BASS, TREBLE, BALANCE, LOUDNESS, TUNING, FUNCTION switch.

Rear panel: Speaker terminals, Phono/Aux inputs, Tape monitor jacks, Antenna terminals, AC power cord.

Input Selection: Phono, Aux, Tuner. Tone Controls: Bass and treble with center detent. Loudness: Compensates for Fletcher-Munson curves. Balance: Adjusts left/right channel balance. Speaker Selector: A/B speakers on/off.

Connecting Components

Speakers: Use 16-gauge or larger speaker wire. Phono: Connect turntable ground wire. Auxiliary: Use RCA cables for line-level sources.

Turn off receiver before making connections.
Connect speakers observing correct polarity (+/-).
Connect turntable to PHONO inputs, attach ground wire.
Connect auxiliary sources to AUX inputs.
Connect FM antenna to 300-ohm terminals.

Tip: Keep signal cables away from power cords to minimize hum.

Tuner Operation

FM stereo reception with tuning meter and signal strength indicator.

Select TUNER on input selector.
Rotate TUNING knob while watching signal meter.
Center tuning meter for strongest signal and lowest distortion.
STEREO indicator lights when receiving stereo broadcast.
For AM reception, connect AM antenna and select AM function.

Note: FM reception quality depends on antenna placement and local signal strength.

Audio Adjustments

Tone controls: Bass affects lower frequencies, treble affects higher frequencies. Loudness: Boosts bass and treble at low volumes. Balance: Adjusts relative volume between left and right channels.

Recommended settings: Start with tone controls at center position, adjust to room acoustics and personal preference. Use loudness control when listening at low volume levels.

Care & Maintenance

Unplug before cleaning. Use soft, dry cloth for exterior. Clean controls with contact cleaner if needed. Keep ventilation openings clear.

CAUTION! Do not use liquids or solvents on wood cabinet. Avoid placing objects on ventilation grilles.

Regulatory Information

FCC compliant for home use. Manufactured to Marantz quality standards. This product may be covered by one or more patents. For service information, contact authorized Marantz service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound	Speaker connections/input selection	Check speaker wires; verify input selector position; check volume setting.
Hum in phono	Ground connection	Ensure turntable ground wire connected to ground terminal.
Poor FM reception	Antenna placement	Reposition FM antenna; check connections.
One channel silent	Balance control/cables	Check balance control position; verify RCA cables fully inserted.
Distorted sound	Overload/speakers	Reduce volume; check speaker impedance compatibility.

Service: Contact authorized Marantz service center for internal repairs.