Hi,
All i want to design a simple Door Intercom .
1) One End which can be placed at Door Side ( handset free ) , which the visitor can use , the visitor will press a button present on the door plate which will cause a ring to occur on the inside intercom.
2) Inside the house there is intercom with handset.
3) The above system should work on 2 wires.
I have designing a 4 wires intercom system using 18 Volts supply when the visitor press the bell at door side,
at door plate LM386 is used , and for Bell KA2410 is used...
iam unable to understand how to design a full duplex door intercom using two wires....
it has something to do with transistor switching or hybird theory i guess which is used in telephone set for converting 4 wires coming from speaker and MIc into two wires,,,
the objective is to transmit current and voice signal on 2 wires only....
let suppose that the above door intercom which i made using 4 wires is need to be converted into 2 wires on which voice and current should go at the same time what intermedaite circuit i have to use....
just think that there is a system on 4 wires and we have to place an mux or decorder or any transistor switching which can converted it into 2 wires system...
All i want to design a simple Door Intercom .
1) One End which can be placed at Door Side ( handset free ) , which the visitor can use , the visitor will press a button present on the door plate which will cause a ring to occur on the inside intercom.
2) Inside the house there is intercom with handset.
3) The above system should work on 2 wires.
I have designing a 4 wires intercom system using 18 Volts supply when the visitor press the bell at door side,
at door plate LM386 is used , and for Bell KA2410 is used...
iam unable to understand how to design a full duplex door intercom using two wires....
it has something to do with transistor switching or hybird theory i guess which is used in telephone set for converting 4 wires coming from speaker and MIc into two wires,,,
the objective is to transmit current and voice signal on 2 wires only....
let suppose that the above door intercom which i made using 4 wires is need to be converted into 2 wires on which voice and current should go at the same time what intermedaite circuit i have to use....
just think that there is a system on 4 wires and we have to place an mux or decorder or any transistor switching which can converted it into 2 wires system...