Eifotoric ZK-502T 50W+50W Bluetooth Amplifier Board

1. Introduction

The Eifotoric ZK-502T is a compact yet powerful 2.0 channel stereo audio amplifier board designed for DIY audio projects. Featuring the TPA3116D2 HIFI chip, Bluetooth 5.0 connectivity, and AUX input, it delivers clear and robust sound with adjustable treble and bass controls. This manual provides detailed instructions for setting up, operating, and maintaining your amplifier board to ensure optimal performance and longevity.

Figure 1.1: Eifotoric ZK-502T Amplifier Board with included accessories.

2. Safety Information

Please read and understand all safety instructions before using this product. Failure to follow these instructions may result in electric shock, fire, or other hazards.

• Ensure the power supply voltage is within the specified range (DC 9-24V). Using an incorrect voltage can damage the device.
• Do not expose the amplifier board to water, moisture, or extreme temperatures.
• Avoid placing the device in direct sunlight or near heat sources.
• Do not disassemble or modify the amplifier board. Refer all servicing to qualified personnel.
• Keep out of reach of children.
• Ensure proper ventilation around the amplifier board to prevent overheating.

3. What's in the Box

Carefully unpack the contents and verify that all items are present and in good condition:

• ZK-502T Stereo Bluetooth Power Amplifier Module x 1
• Heat sink x 1
• 14mm Copper column x 4
• 5mm Copper column mat x 4
• Knob x 3
• Acrylic shell x 2
• 4mm Screw x 8
• 20cm power cable x 1
• Screwdriver x 1
• User Manual (this document)

Figure 3.1: Contents of the ZK-502T package.

4. Product Overview

Familiarize yourself with the various components and controls of the ZK-502T amplifier board:

Figure 4.1: ZK-502T Amplifier Board Component Diagram.

• Bass Control: Adjusts the low-frequency output.
• Treble Control: Adjusts the high-frequency output.
• Power Switch and Volume Control: Rotates to adjust volume; press to power on/off.
• Bluetooth 5.0 Module: Provides wireless audio streaming.
• 3.5MM AUX Input: For wired audio connections.
• DC Input (9-24V): Power supply connection point.
• Heat Sink & TPA3116D2 Chip: Efficient heat dissipation for the main amplifier chip.
• Right Speaker Output: Connects to the right passive speaker.
• Left Speaker Output: Connects to the left passive speaker.

5. Setup

Follow these steps to assemble and connect your ZK-502T amplifier board:

1. Assembly (if required): If your amplifier board arrived as a kit, assemble the acrylic shell, heat sink, and knobs using the provided screws and screwdriver. Refer to Figure 3.1 for guidance.
2. Connect Speakers: Connect your passive speakers to the "Right Speaker Output" and "Left Speaker Output" terminals. Ensure correct polarity (+ to + and - to -). The amplifier supports 4Ω-8Ω speakers with power ratings from 50W to 300W.
3. Connect Audio Source:
   • Bluetooth: For wireless connection, ensure your device (phone, tablet, laptop) has Bluetooth enabled.
   • AUX Input: For wired connection, use a 3.5mm audio cable to connect your audio source (MP3 player, PC, TV) to the "3.5MM AUX Input" port.
4. Connect Power: Connect the provided 20cm power cable to the "DC Input" port on the amplifier board. Then, connect the other end of the power cable to a DC 9-24V power adapter (not included).

Figure 5.1: Connection diagram for audio sources and speakers.

6. Operating Instructions

Once the amplifier board is set up, follow these steps to operate it:

1. Power On: Rotate the Volume Control knob clockwise until you hear a click. The amplifier will power on.
2. Bluetooth Pairing:
   • After powering on, the amplifier will automatically enter Bluetooth pairing mode.
   • On your audio device, search for Bluetooth devices and select "WZ-BT5.0" from the list.
   • Once connected, you will hear a confirmation tone, and you can start playing audio wirelessly.
3. AUX Input Usage: If a 3.5mm audio cable is connected to the AUX input, the amplifier will automatically switch to AUX mode. Disconnect the AUX cable to revert to Bluetooth mode.
4. Adjust Volume: Rotate the Volume Control knob to increase or decrease the audio output level.
5. Adjust Treble and Bass: Use the Treble and Bass control knobs to fine-tune the audio's high and low frequencies according to your preference.
6. Power Off: Rotate the Volume Control knob counter-clockwise until you hear a click to power off the amplifier.

Figure 6.1: Amplifier board in operation with a smartphone.

7. Maintenance

To ensure the longevity and optimal performance of your ZK-502T amplifier board, follow these maintenance guidelines:

• Cleaning: Use a soft, dry cloth to wipe the surface of the amplifier board. Do not use liquid cleaners or abrasive materials.
• Ventilation: Ensure the heat sink and ventilation openings are free from dust and obstructions. Periodically clean with compressed air if necessary.
• Storage: When not in use for extended periods, store the amplifier board in a cool, dry place away from direct sunlight and extreme temperatures.
• Connections: Periodically check all connections (power, speakers, audio input) to ensure they are secure and free from corrosion.

8. Troubleshooting

If you encounter issues with your ZK-502T amplifier board, refer to the following common problems and solutions:

9. Specifications

Key technical specifications for the Eifotoric ZK-502T Amplifier Board:

• Model: ZK-502T
• Amplifier Chip: TPA3116D2
• Channels: 2.0 Stereo
• Output Power: 50W + 50W (Max, dependent on voltage and impedance)
• Power Supply: DC 9-24V (5.5*2.1mm DC Jack)
• Bluetooth Version: 5.0
• Bluetooth Range: Up to 50 feet (unobstructed)
• Audio Inputs: Bluetooth, 3.5mm AUX
• Speaker Impedance: 4Ω-8Ω
• THD (Total Harmonic Distortion): ≤0.1%
• Controls: Volume, Treble, Bass
• Dimensions: Approximately 3.70in (94mm) x 2.76in (70mm) x 0.83in (21mm) (L x W x H)
• Weight: Approximately 4.97 ounces

Figure 9.1: ZK-502T Amplifier Board Dimensions.

Figure 9.2: Output Power vs. Input Voltage and Speaker Impedance.

10. Warranty and Support

Eifotoric provides a satisfaction guarantee for this product. If you have any questions about the product, or if the product has quality problems, please contact Eifotoric customer service at any time. They aim to provide a 100% satisfactory answer.

For support, please refer to the contact information provided with your purchase or visit the official Eifotoric store on Amazon: Eifotoric Amazon Store.