Telephone Circuits


Telephone circuits are designed to deliver audio in the frequency range of 180 Hz - to 3.2kHz. This is adequate for most speech, but a far cry from broadcast or studio audio. The telephone works providing approximately 48 volts of electricity to power the conversation and generate touch tones between your telephone. The telephone company makes your phone ring with approximately 90 volts at 10 Hz. This is something you don't want to personally experience and neither does your audio equipment. 100s of circuits for every hobbyist, technician, student, and design professional. A nice reference tool which includes lots of Telephone circuits. look at these circuit ideas, some of them may need some modification if they are to work as advertised. Ideas along with pretty good descriptions for each circuit.

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