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Circuit operation is as follows. When the phone is on hook the voltage across the phone line is about 48volts dc. When the phone is off hook the voltage will drop to below 10volts dc. When the line voltage is at 48volts the FET is off which causes Q2 and Q3 to be off. When the phone is picked up the FET turns on along with Q2 and Q3 which turns your recorder on. The tape recorder must be in the record mode at all times. As you can see the power source for the circuit is the phone line.

  

hi mail me the details to prasad_devendrappa@yahoo.co.in and will help you.

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sir can u send me all information abt this project at email:rashmi.ambedkar@gmail.com

  

sir can u send me all information abt this project at email:rashmi.ambedkar@gmail.com

  

Sir,

this project is interesting.

can u please mail me d entire details of this project?

to this email id kj.gowrima@gmail.com Quote by --project

  

can u please send me this project details??

sumeshm.pnr@gmail.com

thanx in advance