1-10x Light-Operated Switch Kit DIY Kit With 5V Relay LM393 Electronic Funny DIY

Trigger mode and output mode. Set trigger mode by JMP1 It is DIY kit. User need to weld it. 　　 1-2: Relay is allowed to work. 　　 2-3: Relay is not allowed to work. Set output mode by JMP2 Ceramic capacitor.

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