1. Introduction
The VIKEFON BT-B21/BT-B22 is a versatile 3-in-1 Bluetooth Audio Adapter designed to bring wireless audio capabilities to a wide range of devices. It functions as a Bluetooth transmitter (TX), receiver (RX), and offers a bypass mode, allowing you to connect your TV, PC, vintage stereo systems, and other audio equipment to Bluetooth headphones or speakers. Featuring Bluetooth 5.0 technology, CSR8675 chip, aptX HD, and aptX Low Latency, it ensures high-fidelity sound with minimal delay over an extended range.
2. Package Contents
Please check the box for the following items:
- 1 x Bluetooth Transmitter/Receiver Adapter (BT-B21 or BT-B22)
- 1 x Micro USB charging cable (0.5m/19.6in)
- 1 x 3.5mm audio cable (0.5m/19.6in)
- 1 x 3.5mm jack to 2 RCA plug cables
- 1 x Digital Optical Toslink Audio Cable (1m/39.4in)
- 1 x User Manual
3. Specifications
| Feature | Specification |
|---|---|
| Bluetooth Chip | CSR8675 |
| Bluetooth Version | Bluetooth V5.0 |
| Functionality | Transmitter & Receiver (3-in-1) |
| Bypass Mode | Yes |
| Working Range | Up to 80m/262ft (line-of-sight), 25-35m/80-110ft (indoors) |
| Audio CODEC Support | aptX-HD, aptX Low Latency, SBC |
| Audio Input/Output | Optical, 3.5mm AUX, RCA |
| Status/Codec Display | Yes |
| Support Dual Stream | Yes (connects to 2 headphones/speakers simultaneously) |
| Support Multipoint | Yes |
| NFC Function | Yes (RX mode only) |
| Battery Capacity | 1000mAh |
| Working Time (TX mode) | Up to 15 hours |
| Working Time (RX mode) | Up to 20 hours |
| Charging Time | Approximately 4.5 hours |
| Input Voltage/Current | DC 5V |
| Support Memory Card | No |
| Support Apt-x | Yes |
| Support AAC | Yes |
| Interface | 3.5 MM, Thunderbolt (USB-C for charging) |
| Certification | CE |
4. Setup
4.1. Device Layout and Controls
Familiarize yourself with the device's ports and control buttons:
- Power Switch: ON/OFF/Bypass TX
- Mode Switch: RX/TX
- Ports: 3.5mm RCA port, 3.5mm AUX Input, Optical Input, Optical Output, 3.5mm AUX Output, 3.5mm RCA port (Output)
- Control Buttons: Play/Pause, Last Song/Volume+, Next Song/Volume-
- NFC Area: For quick pairing in RX mode.
4.2. Powering On/Off
- To power on, slide the Power switch to 'ON'.
- To power off, slide the Power switch to 'OFF'.
4.3. Initial Connection
Connect the adapter to your audio source (e.g., TV, PC) or audio output device (e.g., speakers, amplifier) using the appropriate cables (Optical, 3.5mm AUX, or RCA) provided in the package. Ensure the cables are securely connected to the correct input/output ports on both the adapter and your audio equipment.
5. Operating Modes
The VIKEFON Bluetooth adapter supports three main operating modes: Receiver (RX), Transmitter (TX), and Bypass. Select the desired mode using the 'Mode switch' on the device.
5.1. RX (Receiver) Mode
In Receiver mode, the adapter receives audio wirelessly from your Bluetooth-enabled devices (e.g., smartphone, tablet, PC) and outputs it to non-Bluetooth audio equipment like wired speakers, headphones, or car stereos.
- Slide the Mode switch to 'RX'.
- Connect the adapter's audio output (3.5mm AUX or RCA) to your non-Bluetooth speaker/headphone/car stereo's input.
- Enable Bluetooth on your smartphone, tablet, or PC and search for available devices.
- Select 'VIKEFON BT-B21/BT-B22' from the list to pair.
- Once paired, audio from your device will stream to your connected audio equipment.
5.2. TX (Transmitter) Mode
In Transmitter mode, the adapter takes audio from non-Bluetooth sources (e.g., TV, PC, projector) and transmits it wirelessly to Bluetooth headphones or speakers.
- Slide the Mode switch to 'TX'.
- Connect the adapter's audio input (Optical, 3.5mm AUX, or RCA) to your non-Bluetooth audio source (e.g., TV, PC).
- Put your Bluetooth headphones or speaker into pairing mode.
- The adapter will automatically search for and connect to your Bluetooth audio device.
- Once paired, audio from your source will stream to your Bluetooth headphones/speakers.
5.3. Bypass Mode
Bypass mode allows you to connect your TV directly to a speaker system (e.g., soundbar, amplifier) using a wired connection, while still enabling the Bluetooth adapter to function as a transmitter when needed, without disconnecting cables.
- Slide the Power switch to 'Bypass TX'.
- Connect your TV's audio output to the adapter's audio input (Optical, 3.5mm AUX, or RCA).
- Connect the adapter's audio output (Optical, 3.5mm AUX, or RCA) to your speaker system's input.
- In this mode, audio from the TV will pass through the adapter directly to your speaker system. You can then switch to TX mode to transmit audio to Bluetooth headphones/speakers without re-cabling.
6. NFC Function (RX Mode Only)
The adapter supports NFC for quick and easy pairing with compatible smartphones in Receiver (RX) mode.
- Ensure the adapter is in RX mode and powered on.
- Enable NFC on your smartphone.
- Place your smartphone near the NFC area on the adapter.
- Your phone should automatically detect the adapter and prompt for pairing. Confirm the pairing.
7. Dual Connection (TX Mode)
The adapter supports connecting to two Bluetooth headphones or speakers simultaneously in Transmitter (TX) mode, allowing two people to enjoy audio from the same source.
- Ensure the adapter is in TX mode and connected to your audio source.
- Put the first Bluetooth headphone/speaker into pairing mode. The adapter will connect to it.
- Once the first device is connected, put the second Bluetooth headphone/speaker into pairing mode.
- The adapter will automatically search for and connect to the second device.
- Both devices will now receive audio from your source.
8. Battery and Charging
The adapter features a built-in 1000mAh battery for portable use.
- Charging Time: Approximately 4.5 hours for a full charge.
- Working Time: Up to 15 hours in TX mode, up to 20 hours in RX mode.
- Charging: Connect the provided Micro USB charging cable to the adapter's charging port and a 5V USB power source. You can use the device while it is charging.
9. Maintenance
- Keep the device dry. Moisture can damage the internal circuits.
- Do not expose the device to extreme temperatures. High temperatures can shorten the life of electronic devices, damage batteries, and warp or melt certain plastics.
- Do not attempt to open or disassemble the device. Unauthorized repairs can void your warranty.
- Clean the device with a soft, dry cloth. Do not use harsh chemicals or detergents.
- Store the device in a clean, dust-free environment when not in use.
10. User Tips
- Sony Bluetooth Devices: Due to Sony's proprietary Bluetooth encoding methods, pairing with Sony Bluetooth headphones/earphones/speakers in transmitter mode may take longer. Rest assured, they will eventually pair successfully, though the time varies by model.
- Lip-Sync Delay: For a seamless audio-visual experience, especially when watching TV or movies, ensure your Bluetooth headphones or speakers also support aptX Low Latency. If your receiving device does not support aptX Low Latency, you may experience a slight audio delay.
- Power Saving: The device is designed to automatically enter a dormant, power-saving mode after 6 minutes of no connection. This helps conserve battery life.
- Range Optimization: The working range can be affected by environmental factors such as Wi-Fi routers, wireless TV adapters, and physical obstructions. For optimal range, minimize interference and maintain a clear line-of-sight.
11. Troubleshooting
11.1. No Sound or Intermittent Audio
- Check Connections: Ensure all audio cables (Optical, AUX, RCA) are securely plugged into the correct input/output ports on both the adapter and your audio devices.
- Correct Mode: Verify that the adapter is set to the correct mode (RX for receiving, TX for transmitting).
- Volume Levels: Check the volume levels on both the adapter and your connected audio devices.
- Pairing: Ensure the Bluetooth devices are correctly paired. Try unpairing and re-pairing if necessary.
- Interference: Move the adapter and connected devices away from other wireless devices (Wi-Fi routers, cordless phones) that might cause interference.
11.2. Lip-Sync Delay (Audio Lag)
- aptX Low Latency: If experiencing significant delay in TX mode, confirm that both the adapter and your Bluetooth headphones/speakers support aptX Low Latency. If only one device supports it, the benefit will not be fully realized.
- Codec Display: Check the adapter's status display to see which codec is active (LL for Low Latency).
11.3. Difficulty Pairing
- Pairing Mode: Ensure both the adapter and the target Bluetooth device are in pairing mode.
- Distance: Keep devices within close proximity (within 1 meter) during the initial pairing process.
- Clear Previous Pairings: If you have issues, try clearing previous Bluetooth pairings on both the adapter and your device.
- Sony Devices: As noted in User Tips, Sony Bluetooth devices may take longer to pair. Be patient and allow extra time.
11.4. Limited Range
- Obstructions: Walls, furniture, and other physical barriers can reduce Bluetooth range. Try to maintain a clear line-of-sight between the adapter and your connected device.
- Interference: Other electronic devices operating on the 2.4GHz frequency (Wi-Fi, microwaves) can interfere with the Bluetooth signal.
- Antennas: Ensure the adapter's external antennas are properly oriented for optimal signal reception.
12. Warranty and Support
For warranty claims or technical support, please refer to the contact information provided by your retailer or the manufacturer's official website. Keep your purchase receipt as proof of purchase.
