1. Introduction
The ZK-1002M is a versatile 100W+100W Bluetooth 5.0 power audio amplifier board designed for stereo sound systems. It supports multiple audio input methods including Bluetooth, AUX, U disk, and computer USB, making it suitable for various home theater and audio amplification applications. This manual provides detailed instructions for the proper setup, operation, and maintenance of your amplifier board.
2. Safety Information
- Ensure the power supply voltage is within the specified DC5-24V range. Using an incorrect voltage can damage the device.
- Do not connect the amplifier board to a 24V battery pack, as the actual maximum voltage of a 24V battery can exceed 28V, which is beyond the board's safe operating limit.
- Avoid short circuits between components or terminals.
- Ensure proper ventilation to prevent overheating, especially during high-power operation. The large heat sink is crucial for thermal management.
- Keep the device away from water, moisture, and extreme temperatures.
- Only use speakers within the recommended impedance (4-8Ω) and power (20-200W) range.
3. Package Contents
Verify that all items are present in your package:
Figure 3.1: Package Contents
- ZK-1002M Amplifier Board (Main Unit)
- Upper Cover Board
- Lower Cover Board
- Volume Knob
- Key Cap
- M2x12 Copper Pillars (4 pcs)
- M2x7 Screws (8 pcs)
- Power Adapter Cable
- Screwdriver
4. Product Overview
The ZK-1002M features a compact design with multiple input and output options. Familiarize yourself with the various components and connection points:
Figure 4.1: Front Panel Overview
Figure 4.2: Internal Component and Wiring Diagram
Key Components:
- Volume Knob: Controls the output volume.
- ON/OFF Switch: Powers the device on or off.
- AUX IN: 3.5mm jack for analog audio input.
- USB IN: USB port for U disk (USB flash drive) or computer USB audio input.
- DC5-24V Power Input: Power connection point (5.5x2.1 DC head).
- AUX OUT: 3.5mm jack for active speaker output.
- Left/Right Channel Outputs: Screw terminals for passive speaker connection.
- Heat Sink: Large heat sink (36mm*25mm*10mm) for efficient heat dissipation.
5. Setup Instructions
Follow these steps to assemble and connect your ZK-1002M amplifier board:
Figure 5.1: Installation Diagram
- Assemble the Casing: Attach the upper and lower cover boards to the PCB using the M2x12 copper pillars and M2x7 screws. Secure the knob and key cap to their respective shafts.
- Connect Speakers:
- For passive speakers (4-8Ω, 20-200W): Connect the speaker wires to the Left Channel and Right Channel screw terminals. Ensure correct polarity (+ to + and - to -).
- For active speakers: Connect them to the AUX OUT 3.5mm jack.
- Important: You can only use either passive speakers OR active speakers at one time, not both simultaneously.
- Power Supply Connection: Connect a DC5-24V power adapter (with a 5.5x2.1 DC head) to the power input jack. For high power output, a power supply with higher voltage (e.g., 18V, 19V, 24V) and current (above 3A) is recommended.
- Audio Input Source: Choose your desired audio input method (Bluetooth, AUX, U disk, or computer USB).
6. Operating Instructions
Once set up, operate your amplifier board as follows:
- Power On: Flip the ON/OFF switch to the 'ON' position.
- Select Audio Input: The amplifier prioritizes inputs based on connection:
- USB Input: If a U disk (formatted to FAT32, max 32GB) or a computer via USB is connected, this input will be prioritized.
- AUX Input: If no USB input is detected, the amplifier will switch to AUX IN if an audio cable is connected.
- Bluetooth Input: If neither USB nor AUX is connected, the amplifier will automatically enter Bluetooth pairing mode. Search for "Wuzhi Audio" on your device and connect. The Bluetooth range is typically over 15 meters in an unobstructed environment.
- Adjust Volume: Rotate the volume knob to adjust the output level to your speakers.
- Power Off: Flip the ON/OFF switch to the 'OFF' position when not in use.
7. Specifications
Figure 7.1: Key Features
| Parameter | Value |
|---|---|
| Product Name | MINI 2*100W Bluetooth 5.0 Power Amplifier Module |
| Product Model | ZK-1002M |
| Chip Scheme | Domestic amplifier chip |
| Audio Input | Bluetooth + AUX + U disk + Computer USB (plug and play) |
| Power Supply | DC5-24V (high power recommended high voltage) |
| Adapted Speakers | 20-200W; 4-8Ω |
| Channels | Left and right dual channels (stereo) |
| Bluetooth Version | 5.0 (>15 meters, unobstructed) |
| Bluetooth Name | Wuzhi Audio |
| Protection Mechanism | Over current, over heat, short circuit protection |
| Product Size | 60mm x 60mm x 29mm |
| Product Weight | Approx. 104g (including packaging) |
Output Power vs. Voltage/Impedance
The actual output power depends on the power supply voltage, current, and speaker impedance. Higher voltage and current generally lead to higher output power. The following table provides typical power outputs:
| Power Supply Voltage | 8Ω Speaker Output | 4Ω Speaker Output |
|---|---|---|
| 12V | 20W + 20W | 40W + 40W |
| 15V | 35W + 35W | 60W + 60W |
| 19V | 55W + 55W | 80W + 80W |
| 24V | 70W + 70W | 100W + 100W |
8. Maintenance
- Cleaning: Use a dry, soft cloth to clean the amplifier board. Do not use liquid cleaners or solvents.
- Storage: Store the device in a cool, dry place away from direct sunlight and excessive dust.
- Handling: Handle the board carefully to avoid damaging electronic components.
9. Troubleshooting
Common Issues and Solutions
- Q: The sound is distorted or turbid at higher volumes.
- A: This usually indicates insufficient input power or an inadequate power supply/current. Replace your power adapter with one that has a higher voltage rating and sufficient current (e.g., 18V/19V/24V with 3A or more). Ensure the power supply has low ripple and internal resistance.
- Q: The sound becomes stuck or cuts out when loud.
- A: This can happen if the input power is insufficient, or the power supply is intermittently cutting out. Try a larger, more stable power supply. Alternatively, if the output power is too high for the amplifier, the board may be overheating and triggering thermal protection. Reduce the volume or ensure adequate heat dissipation.
- Q: No sound output.
- A: Check all connections: power supply, speakers, and audio input source. Ensure the ON/OFF switch is in the 'ON' position. Verify that the correct input mode is selected (USB, AUX, or Bluetooth) and that the volume is turned up.
- Q: Bluetooth connection issues.
- A: Ensure no USB or AUX cables are connected, as they take precedence. Make sure your device's Bluetooth is on and searching for 'Wuzhi Audio'. Try moving your device closer to the amplifier board to ensure it's within the 15-meter unobstructed range.
- Q: USB flash drive not playing.
- A: Ensure the USB flash drive is formatted to FAT32 and has a maximum capacity of 32GB. Check that the audio files are in a compatible format.
10. User Tips
- For optimal sound quality and to prevent distortion, always use a power supply that can deliver sufficient current, especially when driving higher wattage speakers. A 24V power supply with at least 3A is generally recommended for the full 100W+100W output.
- When connecting speakers, pay close attention to the impedance. Using speakers outside the 4-8Ω range can lead to reduced performance or damage.
- If you experience any intermittent sound or power issues, first check your power adapter. Many issues stem from an unstable or underpowered supply.
- The amplifier board has built-in overcurrent, overheat, and short circuit protection, but it's always best practice to ensure proper wiring and ventilation to avoid triggering these protections unnecessarily.
11. Warranty and Support
For warranty information, technical support, or service inquiries, please contact your original point of purchase or the manufacturer directly. Keep your purchase receipt as proof of purchase.