get me a internal diagram of telephone circuit?

Question

how and what is the total internal circuitry of telephone. how is it built???????????

Answer 1

It's hard to draw an intelligible circuit using ASCII characters, so I'll have to resort to description. A conventional telephone (non-electronic) contains a ringing circuit and a talking circuit. When the handset is on the hook, the ringing circuit is connected: this consists of an electromagnetically operated bell in series with a capacitor (typically about two microfarads). The capacitor blocks the direct current, but allows the 20 Hz ringing current to flow through the bell magnet. (In fact, the thing is designed to be series-resonant at that frequency.) When the handset is picked up, the ringing circuit is disconnected and the talking circuit is connected. This contains a transformer to pass only alternating current to the receiver earpiece, and is arranged to let a limited amount of the speaker's voice reach the earpiece. (This is called sidetone.) There are some other components (diodes and the like) to limit the volume fed to the earpiece and control the amplitude of the signal sent from the phone. Lastly, there is the touch-tone sender, which is a transistor oscillator to generate the tones from pressing the dialing buttons. Early models used inductors, capacitors, and a single transistor, but nowadays it's done with integrated circuits designed for the task.

Answer 2

i think the answer given out here is pretty descriptive and intelligent which is good.. but if u need a more illustrative one, check out howstuffworks.com... you might find one there too!