12V 4 Channel Relay Module with Optocoupler STM8 The meter can only be

The meter can only be used to measure 50-60Hz AC city power

where they are recovered and decoded into independent high-speed clock and data channels

These are Metal Film Resistor with a value of 680k ohm 2W and tolerance of ±5%

Anti saturation diode

and ordinary desktop computers

12V 4 Channel Relay Module with Optocoupler STM8 The meter can only be12V 4 Channel Relay module is able to control various appliances and other equipment with a large current. It can be controlled directly by a Micro controller (Arduino, 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic). Features LED Status indicator High quality screw terminals Mounting Holes Freewheeling Diode to protect your microcontroller Optocoupler to isolate the microcontroller Specification Operating Voltage 12V DC Channel 4 Switching Capacity