??? 07/11/05 03:55 Read: times |
#96971 - I say .. Responding to: ???'s previous message |
Salaam Joseph
I said:
When your telephone is in on-hook state the "TIP" is at about 0v, while "RING" is about -48v with respect to earth ground. When you go off hook, and current is drawn, TIP goes negative and RING goes positive (I mean less negative). A typical off hook condition is TIP at about -20v and ring at about -28v. This means that there is about 8V voltage between the wires going to telephone in normal operation condition. It seems i couldn't say my aim completely In on hook condition the voltage between ring and tip is 8-12 volt,and in off hook condition this is 48-63 vol(depended to country), When you use 2 or 3 battery for power supply,there is no connection between negative polarity and phone lines So it is for having same refrence voltage over the circuit |
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please help me (telepone)![]() | 01/01/70 00:00 |