... , when press button A on the transmitter, receiver channel A goes on 2 seconds then goes ... :[For example 4ch wireless switch]Press remote button A,the receiver relay A is ON,the relay ... B/C/D is OFF;Press remote button B,the receiver relay B is ON,the relay ... A/C/D is OFF;Press remote button C,the receiver relay C is ON,the relay ... A/B/D is OFF;Press remote button D,the receiver relay D is ON,the relay ...