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???
07/11/05 03:55
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#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


List of 43 messages in thread
TopicAuthorDate
First:Wiring Error Detection!            01/01/70 00:00      
   It depends            01/01/70 00:00      
   First observation            01/01/70 00:00      
      First observation            01/01/70 00:00      
   Danger of surges            01/01/70 00:00      
      Sort of.            01/01/70 00:00      
         Sort of            01/01/70 00:00      
         Re: Sort of...            01/01/70 00:00      
            Phone line transients            01/01/70 00:00      
               Schematic of a simple filter            01/01/70 00:00      
                  Research...            01/01/70 00:00      
                     router            01/01/70 00:00      
                     gas discharge tubes            01/01/70 00:00      
                        GDT            01/01/70 00:00      
                        Gas discharge tubes            01/01/70 00:00      
                     Oh dear...            01/01/70 00:00      
                     Gas Tubes            01/01/70 00:00      
                  Or            01/01/70 00:00      
   Ring.            01/01/70 00:00      
   Where's Ring?            01/01/70 00:00      
      I say ..            01/01/70 00:00      
         Telephone systems            01/01/70 00:00      
            Telephone systems            01/01/70 00:00      
               tester            01/01/70 00:00      
                  Yep Jan!            01/01/70 00:00      
                     Even for testing not allowed            01/01/70 00:00      
                        Line simulator            01/01/70 00:00      
                        Another Misunderstanding Kai            01/01/70 00:00      
                        misunderstanding            01/01/70 00:00      
                           Jan            01/01/70 00:00      
                           Confusion...            01/01/70 00:00      
                              quote from my previous post            01/01/70 00:00      
                           It's a current loop ...            01/01/70 00:00      
                              Correction            01/01/70 00:00      
                                 ring?            01/01/70 00:00      
                                    Yes Jan!            01/01/70 00:00      
                                       Agreed            01/01/70 00:00      
                                    it explains a few things, though            01/01/70 00:00      
            Phone Line Ground            01/01/70 00:00      
   Not quite offtopic...            01/01/70 00:00      
   Alternative schematic            01/01/70 00:00      
      Just a simple comparsion !!!!!!!!!!!!!!!            01/01/70 00:00      
      please help me (telepone)            01/01/70 00:00      

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