Analog Services Frequency (Hz)

Analog transmissions move down the phone lines as electromagnetic waves.  The way analog signals travel is expressed in frequency.

Frequency refers to the number of times per second that a wave oscillates or swings back and forth in a complete cycle from its starting point to its end point.

A complete cycle happens when a wave starts at a zero point of voltage, goes to the highest point of voltage on the wave and then down to a negative voltage and back to zero.

The higher the speed of frequency, the more complete cycles of a wave are completed in a period of time.  This speed or frequency is stated in hertz (Hz).

For example, a wave that oscillates back and forth 20 times per second is said to have a speed of 20 hertz or 20 cycles per second.