500m long distance and voice clear wireless voice door phone 1V2

Wireless intercom doorbell is a set of multi-way intercom system,can be uesd in offices,workshops,homes,buildings ect.Using the 2.4G Communications Channel, full-duplex interoperability intercom, communication distance up to 500 meters above

Instructions:1,Boot:Connect the power or battery2,Standby :Receiving mode, the power light flashes every four seconds3,CALLA:First press the ID number, then the CALL button,  enter the main CALL with the red lightB:No response signal 4 seconds means no signal, loud "drops" tones, prompted no signal, ends CALL state.   Signal received, began to sound a beep tone:   A,If no answer, stop beep beep continued for 15 sound, but answer 1 minute,then end the CALL state.   B,If off-hook, beep tone stopped , enter the call state with the green light.   C:Indoor monitor keep a long red light and ring when receive the signal, Will beep 'ding-dong' stop ringing ,about 1 minute,       then entering standby.If off-hook, then stop ringing, the green light to enter the call state   D:Hook: you will hear a "beep". Host can hang up on the call of the process.   E:The indoor monitor is busy, then drops twice, busy prompt ,refund standby.   F:In the process of waiting for the off-hook, press CALL key again      1,If Indoor monitor in the ring , then it doesn't ring again, Outdoor monitor weight 15 beeps, re-timed one minute.      2,If the Indoor monitor not ring, the loud sound 'ding-dong', Outdoor monitorweight 15 beeps, re-timed one minute.