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|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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|hi. thanx for the circuit. is there a replacement for the MOSFET because i have to get it on the Ugandan market.|
|Someone complained the resistor values being excessively high. The reason for that must be to extend the battery life. The circuit is not a good one as it draws significant battery current even when phone line is intact. Since the input impedances seen by the transistors are highly elevated, the circuit wil also be very sensitive to noise.|
|is this device can be use in grounded telephone lines? if doesnt, please give me some schematic to detect grounded telephone line...thnx|
|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.|
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