A telecommunications system, such as a telephone system, involves a contiunous or _____________ signal being____________ into a digital signal. Digital being a signal that is represented by numbers, usually 1s and 0s or ___________ . It then passes along the _________________ path to a ____________ , which changes it into useful information again.
The signals may be changes in voltage, intensity of light or changes in the strength or frequency of radio waves. They may be transmitted using wires, __________________ or radio waves
