| Author | Views | Views Today | Rank | Comments |
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24 |
| Author | Views | Views Today | Rank | Comments |
| 52,261 | 39 | |
24 |
| A while ago I got an email asking for the schematic of a circuit to detect cut phone lines. It didn't take me long to find this circuit in Electronics Now. When the circuit detects that a phone line has been cut, it activates a MOSFET which can be used to drive a relay, motor, etc. It can also be connected to a security system. |
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| This circuit is so easy for the students those work on the minor project and it is very useful to detect the phone tapper. | ||
| this is vary good device.it is vary use full in our day to day life.please if posible send benchmark analaysis to my email . | ||
| is this applicable in wider range of detecting the cut of a wire? | ||
| Can I find a circuit already built? | ||
| its a good circuit but i want to find like that circuits when talking will start and circuits cut the line which are predefine by us for exaple after 5 mins,10 mins and etc. if u have a like this circuits please send it my email address on urgent basis email address is | ||
| if i used the wirless phone it could be work and tell me how i connected with it and if you give me the more and more knowledge plz help me any one knows it thanks | ||
| thank you, very good but sir could you please provides more information about this. | ||
| Oops! I missed the the diode on the input. I guess it does have ring protection after all. Sorry! | ||
| As another poster said "Remove the reference to GND"!! It's a very bad thing to do, and will most certainly set off alarms it Ma Bell! I also agree that most of the resistor values are excessively high. & the input has no protection from the AC Ring voltage! | ||
| soooo good circuit but we need more information about it like data sheet of transistors | ||
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