Isobel Bluetooth 5.4 Transmitter Receiver User Manual

1. Introduction

The Isobel Bluetooth 5.4 Transmitter Receiver is a versatile 3-in-1 portable wireless audio adapter designed to enhance your audio experience across various devices. It functions as a Bluetooth transmitter, a Bluetooth receiver, and an MP3 player with TF card support, providing seamless audio connectivity for your TV, PC, car, airplanes, boats, home stereo systems, and gym equipment.

Equipped with a leading Bluetooth 5.4 chip, this device ensures enhanced stereo sound and stable connections up to 33 feet. Its compact design and multi-functional capabilities make it an ideal solution for converting non-Bluetooth audio sources into wireless ones or enabling wired audio systems to receive Bluetooth signals.

2. Product Features

• Bluetooth 5.4 Technology: Features a leading 5.4 Bluetooth chip for enhanced stereo sound, stability, and an effective range over 33 feet.
• 3-in-1 Functionality: Combines Transmitter (TX), Receiver (RX), and MP3 Player modes in a single device.
• Versatile Connectivity: Connects to any 3.5mm AUX jack, supporting audio streaming from TVs, PCs, car stereos, and other non-Bluetooth sources to Bluetooth speakers/headphones, or receiving audio from Bluetooth devices to wired systems.
• TF Card Playback: Integrated TF/MicroSD card slot allows direct playback of music and audio files without needing a Bluetooth source.
• Long Battery Life: Built-in large capacity battery provides over 12 hours of continuous use. Supports continuous streaming while charging via USB-C.
• Simple Controls: User-friendly buttons for play/pause, volume adjustment, and mode switching.
• Portable Design: Compact and lightweight with a pocket pen holder design for easy portability, suitable for travel in cars, airplanes, or boats.
• Built-in Microphone: Enables hands-free calls in Receiver mode.

3. Package Contents

Please check the package contents upon opening to ensure all items are present:

• Isobel Bluetooth 5.4 Transmitter Receiver (ZF-363)
• 3.5mm Audio Adapter
• USB-C Charging Cable
• User Manual

Image: Package contents including the device, 3.5mm audio adapter, USB charging cable, and user guide.

4. Product Diagram and Components

Image: Front view of the Isobel Bluetooth Transmitter Receiver.

Image: Side view of the Isobel Bluetooth Transmitter Receiver showing the clip and ports.

Component Overview:

• 3.5mm AUX Jack: For audio input/output.
• TF Card Slot: For direct MP3 playback.
• Microphone (MIC): For hands-free calls.
• Reset Button (RST): To reset the device.
• Power On/Off / Play/Pause Button: Central multi-function button.
• Volume Up / Previous Track Button: Top button.
• Volume Down / Next Track Button: Bottom button.
• Mode Switch (RX/MP3/TX): Slider switch on the side to select operating mode.
• Battery Indicator Lights: Four LEDs indicating battery level.
• Status Indicator Light: LED indicating connection status and mode (Blue for RX, Red for TX, Blue+Red for MP3).
• USB-C Charging Port: For charging the device.
• Back Clip: For easy attachment to clothing or bags.

5. Setup and Operation

5.1 Charging the Device

Before first use, fully charge the device. Connect the provided USB-C charging cable to the device's USB-C port and the other end to a USB power source (e.g., computer USB port, USB wall adapter). The battery indicator lights will show charging progress and turn off when fully charged. A full charge takes approximately 1 hour.

5.2 Power On/Off

• Power On: Press and hold the Power On/Off / Play/Pause button for 2 seconds until the indicator light turns on.
• Power Off: Press and hold the Power On/Off / Play/Pause button for 3 seconds until the indicator light turns off.

5.3 Mode Selection

Use the RX/MP3/TX slider switch on the side of the device to select the desired operating mode.

Image: Visual representation of MP3, RX, and TX modes.

5.4 Transmitter (TX) Mode

In TX mode, the device transmits audio from a non-Bluetooth source to Bluetooth headphones or speakers. The indicator light will be solid red.

1. Set the mode switch to "TX".
2. Connect the 3.5mm audio adapter to the device's AUX port and the other end to the audio output jack of your non-Bluetooth device (e.g., TV, PC, CD player).
3. Power on the Isobel device. It will automatically enter pairing mode, and the red indicator light will flash.
4. Place your Bluetooth headphones or speaker in pairing mode.
5. The Isobel device will automatically search for and connect to nearby Bluetooth audio devices. Once connected, the red indicator light will stop flashing and remain solid.
6. Play audio on your source device, and it will be transmitted wirelessly to your Bluetooth headphones/speaker.

Image: Using the device in TX mode to transmit TV audio to headphones.

5.5 Receiver (RX) Mode

In RX mode, the device receives Bluetooth audio from your smartphone, tablet, or other Bluetooth-enabled device and outputs it to wired speakers, headphones, or a car stereo. The indicator light will be solid blue.

1. Set the mode switch to "RX".
2. Connect the 3.5mm audio adapter to the device's AUX port and the other end to the audio input jack of your wired speaker, headphones, or car stereo.
3. Power on the Isobel device. It will automatically enter pairing mode, and the blue indicator light will flash.
4. On your smartphone or tablet, enable Bluetooth and search for "ZF-363" (or similar name). Select it to pair.
5. Once connected, the blue indicator light will stop flashing and remain solid.
6. Play audio on your Bluetooth device, and it will be streamed wirelessly to your connected wired audio system.

Image: Using the device in RX mode for car audio and hands-free calls.

5.6 MP3 Mode (TF Card Playback)

In MP3 mode, the device plays audio files directly from a TF/MicroSD card. The indicator light will be solid blue and red.

1. Set the mode switch to "MP3".
2. Insert a TF/MicroSD card with audio files into the TF card slot.
3. Connect the 3.5mm audio adapter to the device's AUX port and the other end to your wired speaker or headphones.
4. Power on the Isobel device. It will automatically begin playing audio from the TF card.
5. Use the Play/Pause, Volume Up/Previous Track, and Volume Down/Next Track buttons to control playback.

Image: Device in MP3 mode, playing audio from a TF card through a wired speaker.

5.7 Basic Controls

• Play/Pause: Short press the Power On/Off / Play/Pause button.
• Volume Up: Short press the Volume Up / Previous Track button.
• Volume Down: Short press the Volume Down / Next Track button.
• Next Track: Long press the Volume Down / Next Track button.
• Previous Track: Long press the Volume Up / Previous Track button.

5.8 Hands-Free Calls (RX Mode Only)

When in RX mode and connected to a smartphone, the built-in microphone allows for hands-free calling.

• Answer Call: Short press the Power On/Off / Play/Pause button when a call comes in.
• End Call: Short press the Power On/Off / Play/Pause button during a call.
• Reject Call: Long press the Power On/Off / Play/Pause button when a call comes in.

6. Maintenance

• Keep the device dry. Avoid exposure to moisture or liquids.
• Do not expose the device to extreme temperatures.
• Clean the device with a soft, dry cloth. Do not use harsh chemicals or abrasive cleaners.
• Store the device in a cool, dry place when not in use for extended periods.
• Avoid dropping or subjecting the device to strong impacts.

7. Troubleshooting

8. Specifications

• Model: ZF-363
• Bluetooth Version: 5.4
• Operating Modes: Transmitter (TX), Receiver (RX), MP3 Player
• Connectivity: 3.5mm AUX Jack, TF/MicroSD Card Slot
• Wireless Range: Over 33 feet (10-15 meters)
• Battery Type: Lithium Polymer (included)
• Charging Time: Approximately 1 hour
• Usage Time: Approximately 12+ hours
• Power Source: Battery Powered (USB-C charging)
• Dimensions: 2.36 x 0.83 x 0.74 inches (approx. 60 x 21 x 19 mm)
• Weight: 0.705 ounces (approx. 20 grams)
• Material: Plastic
• Special Features: Built-in Microphone for Hands-Free Calls, TF Card Playback, Portable Design with Back Clip.

9. Safety Information

Please read and follow these safety guidelines to ensure proper and safe use of the device:

• When using the USB data cable to transmit audio on a PC, only the volume of the playback software (music player, video player) or the Bluetooth speaker/headset can be adjusted.
• This device does not support voice calls or voice assistant functions when connected via USB for audio transmission.
• Do not disassemble, repair, or modify the device yourself. This may cause damage, electric shock, or fire.
• Keep the device away from water, fire, high temperatures, and corrosive substances.
• Dispose of the device and its battery responsibly according to local regulations. Do not dispose of with household waste.

10. Warranty and Support

Isobel is committed to providing high-quality products and customer satisfaction. If you encounter any product quality issues, we offer a no-hassle refund, return, or exchange service.

For further assistance, troubleshooting, or warranty claims, please contact Isobel customer support through the retailer where you purchased the product or visit the official Isobel store page on Amazon:

Visit the Isobel Store on Amazon