1. Introduction
The FMIIFMS Bluetooth 5.4 Transceiver Pro (Model BT-108) is a versatile 2-in-1 device designed to transform any non-Bluetooth audio equipment into a wireless audio hub. It functions as both a Bluetooth transmitter (TX Mode) and a Bluetooth receiver (RX Mode), allowing you to stream audio to or from a wide range of devices. This manual provides detailed instructions for setup, operation, and maintenance to ensure optimal performance.
2. Package Contents
- 1 x FMIIFMS Bluetooth 5.4 Transceiver Pro (Model BT-108)
- 1 x USB-C Charging Cable
- 1 x 3.5mm Audio Cable
- 1 x Dual 3.5mm Airplane Adapter
- 1 x User Manual
3. Product Overview
Familiarize yourself with the device's components and indicators.
Figure 3.1: FMIIFMS Bluetooth 5.4 Transceiver Pro and accessories.
Figure 3.2: Side view illustrating the TX/RX mode switch and audio port.
Controls and Indicators:
- Multifunction Button (Power/Play/Pause/Call): Press and hold to power on/off. Short press for play/pause. Used for call management.
- Volume Up / Next Track Button: Short press for volume up. Long press for next track.
- Volume Down / Previous Track Button: Short press for volume down. Long press for previous track.
- TX/RX Mode Switch: Toggle between Transmitter (TX) and Receiver (RX) modes.
- Status Indicators (LEDs): Indicate power, pairing status, and mode.
- 3.5mm Audio Jack: For connecting to audio sources or output devices.
- USB-C Port: For charging the device.
4. Setup
4.1. Transmitter Mode (TX)
Use TX mode to stream audio from non-Bluetooth devices (e.g., TV, PC, airplane entertainment system) to your Bluetooth headphones or speakers.
- Switch the device to TX mode using the side switch.
- Connect the 3.5mm audio cable from the Transceiver Pro's audio jack to the audio output port (e.g., headphone jack) of your non-Bluetooth device. For airplane entertainment systems, use the included dual 3.5mm adapter if required.
- Power on the Transceiver Pro by pressing and holding the Multifunction Button. The TX indicator light will flash, indicating it is in pairing mode.
- Place your Bluetooth headphones or speakers into pairing mode.
- The Transceiver Pro will automatically search for and connect to your Bluetooth audio device. Once connected, the TX indicator light will remain solid.
- Dual Device Connection (TX Mode): To connect a second pair of Bluetooth headphones/speakers, put the second device into pairing mode. Then, short press the Multifunction Button on the Transceiver Pro. The TX indicator will flash again, and it will connect to the second device. Both devices will then receive audio simultaneously.
Figure 4.1: Using the Transceiver Pro in TX mode on an airplane.
Figure 4.2: Sharing TV audio with two Bluetooth headphones in TX mode.
4.2. Receiver Mode (RX)
Use RX mode to receive audio from your Bluetooth-enabled phone or tablet and play it through non-Bluetooth speakers, car audio systems, or home stereos.
- Switch the device to RX mode using the side switch.
- Connect the 3.5mm audio cable from the Transceiver Pro's audio jack to the audio input port (e.g., AUX-in) of your non-Bluetooth speaker, car stereo, or home stereo.
- Power on the Transceiver Pro by pressing and holding the Multifunction Button. The RX indicator light will flash, indicating it is in pairing mode.
- On your phone or tablet, enable Bluetooth and search for available devices. Select "FMIIFMS BT-108" (or similar) from the list to pair.
- Once connected, the RX indicator light will remain solid. You can now stream audio from your phone/tablet to your connected audio system.
- Dual Device Connection (RX Mode): To connect a second Bluetooth audio source (e.g., another phone), put the second device into pairing mode. Then, short press the Multifunction Button on the Transceiver Pro. The RX indicator will flash again, and it will connect to the second device. You can switch between the two connected devices for audio playback.
Figure 4.3: Using the Transceiver Pro in RX mode in a car.
Figure 4.4: Connecting the Transceiver Pro to a home stereo system in RX mode.
Figure 4.5: Visual guide for RX and TX mode connections.
5. Operating Instructions
5.1. Power On/Off
- Power On: Press and hold the Multifunction Button for approximately 3 seconds until the indicator lights illuminate.
- Power Off: Press and hold the Multifunction Button for approximately 3 seconds until the indicator lights turn off.
5.2. Music Playback Controls (RX Mode)
- Play/Pause: Short press the Multifunction Button.
- Next Track: Long press the Volume Up button.
- Previous Track: Long press the Volume Down button.
- Volume Up: Short press the Volume Up button.
- Volume Down: Short press the Volume Down button.
5.3. Call Management (RX Mode)
- Answer/End Call: Short press the Multifunction Button.
- Reject Call: Long press the Multifunction Button for 2 seconds.
- Redial Last Number: Double-press the Multifunction Button.
- Privacy Call Mode: During a call, press and hold the Multifunction Button for 3 seconds to switch the call audio between the Transceiver Pro and your phone.
Figure 5.1: Activating Privacy Call Mode.
6. Charging
The Transceiver Pro has a built-in rechargeable battery. When the battery is low, the indicator light will flash. Connect the included USB-C charging cable to the device's USB-C port and to a standard USB power adapter (not included).
- Charging Time: Approximately 1.5 hours for a full charge.
- Playtime: Over 15 hours on a full charge.
- The device can be used while charging.
7. Maintenance
- Clean the device with a soft, dry cloth. Do not use harsh chemicals or abrasive materials.
- Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
- Avoid dropping or subjecting the device to strong impacts.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Low battery. | Charge the device for at least 30 minutes. |
| Cannot pair with a Bluetooth device. | Device not in pairing mode; Bluetooth device too far; interference. | Ensure Transceiver Pro is in correct TX/RX mode and flashing. Place devices closer. Turn off other Bluetooth devices. |
| No sound or poor sound quality. | Incorrect cable connection; volume too low; source device issue. | Check all cable connections. Adjust volume on both Transceiver Pro and connected devices. Test with another audio source. |
| Dual connection not working. | Second device not in pairing mode or already connected to another device. | Ensure the second device is in pairing mode before attempting to connect. Disconnect from other devices if necessary. |
9. Specifications
| Feature | Detail |
|---|---|
| Model Number | BT-108 |
| Bluetooth Version | 5.4 |
| Operating Modes | Transmitter (TX), Receiver (RX) |
| Audio Interface | 3.5mm AUX |
| Charging Port | USB-C |
| Battery Life (Playtime) | 15+ hours |
| Charging Time | Approx. 1.5 hours |
| Product Dimensions | 4 x 3 x 0.6 inches (101.6 x 76.2 x 15.24 mm) |
| Item Weight | 1.94 ounces (55 grams) |
| Compatible Devices | Headphones, Speakers, Smart TV, Desktop, Laptop, Game Console, Smartphone, Tablet |
Figure 9.1: Product dimensions.
10. Safety Information
Improper battery handling may lead to fire or explosion. Please dispose of used batteries according to local regulations. Do not expose the device to extreme temperatures, moisture, or direct sunlight. Do not attempt to disassemble or repair the device yourself.
11. Warranty and Support
FMIIFMS products are designed for reliability and performance. For any questions, technical support, or warranty inquiries, please refer to the contact information provided with your purchase or visit the official FMIIFMS website. Please retain your proof of purchase for warranty claims.