18/02/2026
W8128 wireless microphone system board connection
Pin Connections
The board features several labeled output pins for integration into an audio system:
3OUT / 9OUT: These are likely audio output pins (often for different channels or signal types).
GND: Common ground connection.
+8V: Power input pin, typically requiring an 8-volt DC supply.
KC: Often stands for "Key Control" or a squelch control signal used to mute the audio when no transmitter signal is detected.
To wire this board, connect the pins as follows:
Pin Label Function Connection Details
+8V Power Input Connect to a stable 8V DC power supply.
GND Ground Connect to the common ground of your power supply and audio system.
3OUT Audio Output A Signal output (typically for channel A or a specific frequency). Connect to the "Signal" or "+" input of your amplifier.
9OUT Audio Output B Secondary signal output. Use this if your system supports dual outputs or if 3OUT does not provide signal.
KC Key Control Often used for squelch or mute control. If the audio is silent when it shouldn't be, try connecting this to ground or leaving it disconnected.
Additional Setup Tips
Antenna: The small pads at the very top or bottom of the board (near the larger mounting holes) are typically where the antenna wire is soldered.
Signal Noise: Ensure you use shielded audio cables for the 3OUT or 9OUT connections to prevent interference and buzzing in the audio.
