Hi, I am a Graduate Student.I am fabricating the Phone Busy Indicator as a Hybrid Circuit as part of my Thick Film Engineering Project.I already completed the Layout for the circuit.I need help in interfacing the Phone Busy Circuit with the Phone Line Supply.Also how do i test the Circuit on Bread Board before i put it against the Phone Bus.(what Power supply range).Your Suggestions will be greatly appreciated. Thanks a bunch
You can test the circuit with a variable DC power supply that goes to about 60V. Just simulate the voltages of the phone line (about 40V at rest, 10V "off hook").
Aaron, when i meant the phone line supply, i meant the incoming phone line.I have this persisting doubt.what do these tip and ring before the bridge rectifier mean in the circuit.If i fabricate this circuit, where does the circuit gets attached. directly on the phone line or to the telephone instrument through a modular jack??is it attached before the telephone ot after the telephone?please clarify on these very basic doubts of mine. Thanks and regards, Ananth
Aaron, can you in simple lay- man's terms elaborate the switching of the transistors and the resultant switching of the LEDs.I just want to corroborate my understanding of the circuit for the purpose of my technical Write up for the project. Thanks and Regards,