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

You can visit http://www.hbeonlabs.com/projectsguidance.htm and http://www.finalyearstudentprojects.com/ for alot of final year engineering projects and guidance for implementing them. You can also download the free synopsis of these project from our website mentioned above. Please forward this to your friend who needs help in their final year projects.

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

You can visit http://www.hbeonlabs.com/projectsguidance.htm and http://www.finalyearstudentprojects.com/ for alot of final year engineering projects and guidance for implementing them. You can also download the free synopsis of these project from our website mentioned above. Please forward this to your friend who needs help in their final year projects.

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

this project is interesting.

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

to this email id kj.gowrima@gmail.com

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can u please send me this project details??

sumeshm.pnr@gmail.com

thanx in advance
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