SANSUI F21 Portable FM Radio Bluetooth 5.0 Speaker User Manual

1. Introduction

Thank you for choosing the SANSUI F21 multimedia player. This manual provides detailed instructions to help you understand and utilize all the functions of your device effectively. Please read it thoroughly before use.

The SANSUI F21 is a portable mini radio and Bluetooth 5.0 speaker, designed for versatile audio playback and recording. It features a compact design, high-quality sound, and multiple playback options including FM radio, TF card, and USB disk. It also supports Bluetooth connectivity and full-mode recording.

Figure 1: SANSUI F21 Portable FM Radio Bluetooth 5.0 Speaker (Black and Green models)

2. Product Overview

The SANSUI F21 features a user-friendly interface with a digital display, numeric keypad, and various control buttons. It includes a retractable antenna for FM reception, multiple ports for connectivity, and a built-in speaker.

Figure 2: Product Diagram with Key Components

1. Recording Key
2. Mode Key
3. Previous Song / Fast Rewind
4. Play / Pause / Delete Key
5. Next Song / Fast Forward
6. Numeric Keypad (0-9)
7. Headphone Jack
8. USB Disk Socket
9. DC 5V Charging Interface
10. TF Card Socket
11. Volume Increase/Decrease Toggle Switch
12. ON/OFF Switch

3. Setup

3.1. Unpacking

Carefully unpack the product and ensure all accessories are present:

• Host Computer (Radio) x1
• TYPE-C interface charging cable x1
• Lanyard x1
• Headphones x1
• Manual x1
• Certificate x1

3.2. Charging the Battery

The device comes with a built-in 750mAh polymer lithium battery. Before first use, or if the device has not been used for a long time, fully charge the battery.

1. Plug the charging cable into the DC5V port (9) on the device.
2. Connect the other end of the charging cable to a suitable USB power adapter (not included) or a computer's USB port.
3. During charging, the battery symbol on the display will blink.
4. Once fully charged, the battery symbol will remain steadily lit.

Figure 3: USB Fast Charging

3.3. Power On/Off

To power on the device, slide the ON/OFF switch (12) to the 'ON' position. To power off, slide it to the 'OFF' position.

4. Operating Instructions

4.1. Mode Switching

Short press the Mode key (2) to cycle through available modes: Bluetooth, FM Radio, TF Card Playback, and U Disk Playback.

4.2. FM Radio Operation

1. Switch to FM Radio mode using the Mode key (2).
2. Automatic Search: In FM Radio mode, long press the Mode key (2) to automatically search for and save radio stations.
3. Manual Tuning: Use the numeric keys (6) to directly enter the desired radio frequency. For example, to tune to 107.5 MHz, press '1', '0', '7', '5'.
4. Channel Navigation: Short press the Previous Song (3) or Next Song (5) keys to switch between saved radio channels.

4.3. Bluetooth Connectivity

1. Switch to Bluetooth mode using the Mode key (2). The display will show "BLUE" or a similar indicator.
2. On your mobile device, enable Bluetooth and search for available devices.
3. Select "SANSUI F21" (or similar name) from the list to pair.
4. Once connected, you can play audio from your mobile device through the speaker.

Figure 4: Bluetooth 5.0 for fast and stable signal transmission.

4.4. TF Card / U Disk Playback

The device supports MP3, WAV, FLAC, and APE lossless music formats.

1. Insert a TF card into the TF Card Socket (10) or a U disk into the USB Disk Socket (8).
2. Switch to TF Card or U Disk mode using the Mode key (2).
3. Track Selection: Short press the Previous Song (3) or Next Song (5) keys to switch tracks.
4. Fast Forward/Rewind: Long press the Previous Song (3) or Next Song (5) keys for fast rewind or fast forward.
5. Direct Track Selection: In MP3 playback mode, use the numeric keys (6) to directly select a track by its number.

Figure 5: TF Card/U Disk Playback options.

4.5. Playback Controls

• Play/Pause: Short press the Play/Pause/Delete key (4) to play or pause music.
• Volume Control: Use the Volume Increase/Decrease toggle switch (11) to adjust the volume. Toggle towards '-' to decrease, and towards '+' to increase.

4.6. Recording Function

The device supports full-mode recording, including MIC sound in U disk/TF card mode, and machine sound in Bluetooth/Radio mode.

1. In U disk or TF card music playback mode, long press the Recording key (1) to start recording.
2. Press the Recording key (1) again to end the recording.
3. Short press the Recording key (1) to play back the recorded file from the U disk or TF card.
4. To delete a recording: In MP3 mode, long press the Play/Pause/Delete key (4) to initiate deletion. Short press again to confirm. If no action is taken within 5 seconds, the deletion function will exit.

Figure 6: One-touch Full Mode Recording.

4.7. Headphone Use

Insert headphones into the Headphone Jack (7) for private listening. This activates a "no-disturb mode."

Figure 7: Enjoying music with headphones.

5. Maintenance

• Cleaning: This product is not waterproof. Do not use liquids to clean it. It is recommended to clean the device with a soft, dry cloth.
• Storage: If the device will not be used for a long time, fully charge it, power it off, and store it in a dry environment. Avoid storing it in environments exceeding 40°C or below -10°C.
• Battery Care: Do not allow the battery to be completely discharged for extended periods, as this can cause irreversible damage.
• Dust and Sand Protection: Pay attention to protecting the device from dust and sand during use.

6. Troubleshooting

General Precautions:

• If smoke or a scorched smell occurs during charging, immediately cut off power and stop using the device. Contact the manufacturer for repair.
• If the device falls into water, do not use it again. Contact the vendor or factory for repair. Unauthorized use or charging in such a state can lead to burning or short-circuit fire.
• If foreign objects are found inside the device, discontinue use and contact the vendor or factory for repair. Do not attempt to disassemble the device without permission, as this may damage internal components.

7. Specifications

Figure 8: Product Parameters

8. User Tips

• Maximize Recording: The F21 supports recording from various sources including FM radio and Bluetooth audio, as well as external audio via its microphone in TF/USB mode. Experiment with different modes to capture your desired audio.
• Portable Convenience: Utilize the included lanyard to easily carry the compact radio, making it ideal for home, office, outdoor travel, sports, and leisure.
• Lossless Audio: For the best sound quality, use TF cards or U disks with FLAC and APE lossless music files.

9. Warranty and Support

For any issues not covered in the troubleshooting section, or for repair services, please contact the vendor or factory directly. Do not attempt to repair the device yourself, as this may void any potential warranty and could cause further damage.

For additional information and detailed diagrams, you may refer to the official user manual PDF: SANSUI F21 User Manual (PDF).