Marantz 2238B User Manual

The Marantz 2238B is a classic stereo receiver featuring 38 watts per channel, high-quality audio performance, and the iconic Marantz design. This vintage audio component includes AM/FM tuner, phono input for turntables, tape monitor, loudness control, and multiple audio inputs. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Devices 7. Tuning and Audio Adjustment 8. Maintenance 9. Regulatory Information 10. Troubleshooting

Features at a Glance

Key components: Front panel controls, AM/FM tuner, Phono input, Tape monitor, Speaker outputs, 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)
Tape Monitor	Tape 1 and Tape 2 inputs/outputs
Loudness Control	Compensates for low volume listening
Bass/Treble Controls	Separate bass and treble adjustment
Speaker Selector	A/B speaker selection
Headphone Jack	For private listening
Balance Control	Left/right channel balance
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 turntable connection.
Connect audio sources: Use AUX input for CD players, tape decks, etc.
Connect antenna: Attach FM antenna to antenna terminals.
Plug into AC power.

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

First-Time Setup

Power on receiver; follow initial setup procedure.

Speaker connection: Connect speakers to A or B terminals observing polarity.
Source selection: Rotate input selector to desired source (Phono, Aux, Tuner).
Tuner setup: Extend FM antenna and tune to desired station.
Volume adjustment: Start with volume at minimum, gradually increase.
Tone controls: Set bass and treble to neutral position initially.

CAUTION! Always turn volume to minimum before powering on or changing sources.

Specifications

Power Output: 38 watts per channel (8 ohms, 20Hz-20kHz)
Total Harmonic Distortion: 0.08%
Frequency Response: 10Hz-50kHz (+0, -3dB)
Input Sensitivity: Phono: 2.5mV, Aux: 150mV
Signal-to-Noise Ratio: Phono: 76dB, Aux: 90dB
Tuner Section: FM sensitivity: 1.8uV, AM sensitivity: 30uV
Dimensions: 17-3/8" W x 5-1/4" H x 14-1/2" D
Weight: 22 lbs
Power Requirements: 120V AC, 60Hz, 180W

Controls and Settings

Front panel controls: Power, Volume, Balance, Bass, Treble, Loudness, Input Selector, Speaker Selector, Tuning.

Input Selector: Phono, Aux, Tuner, Tape 1, Tape 2. Speaker Selector: A, B, A+B, Off. Tone Controls: Bass ±10dB at 50Hz, Treble ±10dB at 15kHz. Loudness: Compensates for Fletcher-Munson curve at low volumes.

Tuner: Tuning knob with signal strength meter, FM muting, Mono/stereo selection. Tape: Tape monitor switches for Tape 1 and Tape 2.

Connecting Devices

Phono: For turntables (use ground wire). Aux: For CD players, streaming devices. Tape: Tape deck inputs/outputs.

Turn off receiver before connecting devices.
Match input types (phono to phono, line level to aux).
Connect ground wire from turntable to ground terminal.
Use proper cables (RCA for audio connections).
Select appropriate input on front panel.

Tip: Keep audio cables away from power cords to reduce hum and interference.

Tuning and Audio Adjustment

FM tuning procedure and audio optimization.

Select Tuner input on selector.
Rotate tuning knob until station is centered on tuning meter.
Adjust antenna for best reception.
Use bass/treble controls to suit listening preference.
Engage loudness control for low-volume listening.
Use balance control to center soundstage.
Tape monitoring: Engage tape monitor when using tape deck.

WARNING! Do not operate with speakers disconnected. Avoid extreme volume levels.

Maintenance

Regular cleaning and care procedures.

Unplug before cleaning.
Use soft, dry cloth for front panel and knobs.
Clean controls with contact cleaner if scratchy.
Keep ventilation openings clear.
Avoid liquid cleaners and aerosols.

CAUTION! Do not use abrasive cleaners. Keep away from moisture and extreme temperatures.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. Manufactured to meet industry standards for audio equipment. For service or technical support, contact authorized Marantz service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound from speakers	Speaker selector, volume	Check speaker selector position; ensure volume is up; verify speaker connections.
Hum or buzz	Grounding, cables	Check turntable ground connection; separate audio and power cables.
Poor FM reception	Antenna, location	Extend FM antenna fully; reposition for better reception.
One channel silent	Balance, connections	Check balance control; verify RCA cables fully inserted.
Scratchy controls	Dirty contacts	Clean controls with contact cleaner; rotate knobs repeatedly.
Overheating	Ventilation, impedance	Ensure proper ventilation; check speaker impedance matches requirements.

Service: Contact authorized Marantz service center for internal repairs.