Introduction
The DISOUR Upgrade C28 is a versatile 2-in-1 Bluetooth 5.3 audio adapter designed to seamlessly switch between transmitter (TX) and receiver (RX) modes. This device allows you to add Bluetooth functionality to non-Bluetooth audio equipment, enabling wireless audio streaming to or from your devices. It features a compact design, a built-in rechargeable battery, and a 3.5mm audio interface, making it ideal for use with car audio systems, TVs, PCs, headphones, and speakers.
Product overview, showing 2-in-1 functionality and Bluetooth 5.3.
Package Contents
Please check the package for the following items:
- 1 x C28 Bluetooth Transmitter Receiver
- 1 x USB Charging Cable
- 1 x 3.5mm Audio Head (AUX cable)
- 1 x User Manual
Package contents including the C28 device, charging cable, 3.5mm audio head, and user manual.
Specifications
| Feature | Detail |
|---|---|
| Model Number | Upgrade C28 |
| Wireless Type | Bluetooth 5.3 |
| Interface | 3.5 MM Audio AUX |
| Content | AUDIO |
| Battery Capacity | 140 mA |
| Life Time | Approximately 4 hours |
| Working Range | Up to 10 meters (open area, without obstacles) |
| Product Size (L x W x H) | 59.5mm x 22mm x 12mm |
| Certification | CE |
Setup
Device Overview and Controls
The C28 features a multifunction button for power and play/pause, an AUX in/out port, a transmitter/receiver switch, a microphone, an indicator light, and a 5V/1A charging port.
Interface diagram of the C28, labeling buttons, ports, and switches.
- Multifunction Button (Power/Play/Pause)
- AUX in/out
- Transmitter and Receiver Switch (RX/TX)
- Microphone
- Indicator Light
- 5V/1A Charging Port
Initial Charging
Before first use, or if the battery is low, please fully charge the C28 using the provided USB charging cable. Connect the cable to the 5V/1A charging port on the device and a suitable USB power source. The indicator light will show charging status (usually red while charging, off when fully charged).
Diagram showing the C28's battery life (4 hours) and charging capability.
Operating Instructions
Receiver Mode (RX)
Use RX mode to receive audio wirelessly from a Bluetooth-enabled device (e.g., smartphone, tablet) and output it to a non-Bluetooth audio system (e.g., car stereo, wired headphones, home speaker).
- Ensure the C28 is charged.
- Connect the C28 to your audio device (e.g., car AUX input, wired speaker) using the 3.5mm AUX cable.
- Slide the switch button on the C28 to the RX position.
- Turn on the C28 by long-pressing the multifunction button. The blue indicator light will flash quickly, indicating it is ready for pairing.
- On your phone or other Bluetooth device, search for "C28" in the Bluetooth settings and select it to pair.
- Once paired, the blue light will remain solid, and you can now stream audio wirelessly.
Diagram illustrating Receiver (RX) mode, connecting the C28 to a wired speaker and receiving audio from a phone.
Image showing the C28 connected to a car's AUX input, enabling wireless audio.
Transmitter Mode (TX)
Use TX mode to transmit audio wirelessly from a non-Bluetooth audio source (e.g., TV, PC, MP3 player) to a Bluetooth-enabled receiving device (e.g., Bluetooth headphones, wireless speaker).
- Ensure the C28 is charged.
- Connect the C28 to your audio source device (e.g., TV audio out, PC headphone jack) using the 3.5mm AUX cable.
- Slide the switch button on the C28 to the TX position.
- Turn on the C28 by long-pressing the multifunction button. The red indicator light will flash quickly, indicating it is ready for pairing.
- Put your Bluetooth receiving device (e.g., headphones, speaker) into pairing mode. The C28 will automatically search for and connect to it.
- Once connected, the red indicator light will illuminate solid, and audio from your source device will be transmitted wirelessly.
Diagram illustrating Transmitter (TX) mode, connecting the C28 to a TV/PC and transmitting audio to wireless headphones/speakers.
Image showing a person watching TV with wireless headphones, enabled by the C28 in TX mode.
Maintenance
Charging and Battery Care
- Charge the device fully before each use for optimal performance.
- The built-in rechargeable lithium battery provides approximately 4 hours of use on a full charge.
- If the battery is low, the device can be used while charging, providing continuous operation.
- Avoid exposing the device to extreme temperatures, as this can affect battery life.
Cleaning and Storage
- Wipe the device with a soft, dry cloth to clean. Do not use liquid cleaners or aerosols.
- Store the device in a cool, dry place away from direct sunlight and moisture when not in use.
- Keep out of reach of children.
Troubleshooting
- Device not pairing/connecting:
- Ensure the C28 is in the correct mode (RX or TX) for your intended use.
- Make sure the C28 and the target device are both in pairing mode (flashing indicator light).
- Check that the devices are within the 10-meter working range and there are no significant obstacles.
- Turn both devices off and on again, then attempt pairing.
- Low audio quality or volume:
- Verify the volume levels on both the C28 (if applicable) and the connected audio source/receiving device.
- Ensure the 3.5mm AUX cable is securely connected to both the C28 and the audio equipment.
- Try using a different 3.5mm AUX cable to rule out cable issues.
- Some users have noted that in TX mode, the audio signal might be mono. This is a characteristic of some adapters and not necessarily a defect.
- Battery drains quickly:
- Ensure the device is fully charged before use.
- Battery life can vary based on usage patterns and volume levels.
- If the battery life is significantly shorter than the stated 4 hours, contact support.
- Device does not turn on automatically in car:
- The C28 is a battery-powered device and typically requires manual power-on by long-pressing the multifunction button each time you wish to use it, especially in car environments where power cycling might not automatically activate it.
User Tips
- Optimal Range: For the best connection and sound quality, maintain a clear line of sight between the C28 and the connected Bluetooth device, especially when approaching the 10-meter maximum range.
- Continuous Playback: If the battery is running low during use, you can connect the charging cable and continue using the C28 while it charges, ensuring uninterrupted audio.
- Quick Setup: Many users find the C28 connects quickly and is easy to set up, making it convenient for on-the-go use or quick integration into home systems.
- Car Use: When using in a car, remember that you will likely need to manually turn on the C28 each time you start your vehicle, as it does not typically auto-power on with the car's ignition.
Frequently Asked Questions (FAQ)
- Q: Does the C28 have Bluetooth?
- A: Yes, the DISOUR Upgrade C28 features Bluetooth 5.3 for wireless audio transmission and reception.
- Q: Can multiple people connect to the C28 at the same time?
- A: Typically, Bluetooth audio adapters like the C28 are designed to connect to one device at a time for either transmitting or receiving audio.
- Q: Does it work with iPhone 14 Plus?
- A: Yes, as a standard Bluetooth 5.3 device, the C28 is compatible with most Bluetooth-enabled smartphones, including the iPhone 14 Plus, for both transmitting and receiving audio.
- Q: When connected to my car, it doesn't turn on automatically; I have to press the button. Is this normal?
- A: Yes, this is normal behavior for many battery-powered Bluetooth adapters. The C28 requires a manual long-press of the multifunction button to power on, even if it's connected to a power source in your car.
Warranty and Support
For any issues, questions, or warranty claims regarding your DISOUR Upgrade C28 Bluetooth Adapter, please contact the seller or manufacturer directly. Refer to the original packaging or purchase documentation for specific contact information.
A detailed user manual in PDF format is also available for download: View User Manual (PDF)