PART A: HOW A RADIO STATION OPERATES

SOUND

Sound travels through air as pressure waves or rapid fluctuations in air pressure. The rates of fluctuation in air pressure that we humans can perceive as sound is commonly said to vary between 20 cycles per second and 20,000 cycles per second. (Cycles per second are also known as Hertz. 20,000 cycles per second is 20 kilohertz or kHz.). In fact, few adult individuals can hear above 15 to 17 kHz. High frequency hearing loss occurs naturally as we age but, in addition to that, many young people have been careless in their exposure to high sound pressure levels — such as at rock concerts or with headphones — resulting in premature high frequency hearing loss.

When sound waves hit a microphone, the pressure fluctuations are converted into fluctuations of electric voltage on a wire. Voltage is to electricity as pressure is to air. It is a kind of electric pressure. The higher the voltage, the greater the pressure with which electrons are pushed through a wire. Louder sounds are associated with higher sound pressure levels (SPLs) and produce larger voltage fluctuations at the microphone.

SIGNALS

The fluctuations of voltage that represent sound and travel down a wire are known as an audio signal. Signals are translated back into sounds by loudspeakers and headphones. The fluctuating voltage induces a fluctuation in the position of a diaphragm or speaker cone. The moving speaker cone causes local fluctuations in air pressure, which propagate through the air as sound. The propagation of sound waves through air is analogous to the propagation of waves on the surface of water.

Audio signals can be stored in a variety of ways. A phonograph record stores signals as fluctuations in the position of a groove. As the phonograph needle is dragged through the groove, it translates the groove position fluctuations back into electrical signals.

Signals can be stored on tape in another analogous form: fluctuations of magnetism. Tape heads translate electrical signals into magnetic signals laid down on the tape and vice versa. Signals can also be translated into numbers and stored on CDs as fluctuations in the reflectivity of a shiny surface or, again, as magnetic fluctuations such as on Digital Audio Tape (DAT) or minidiscs.

RADIO AND MODULATION

Radio propagates sound signals long distances through air and space by the use of high frequency carrier waves. The sound signal is imposed on the carrier wave by a process called modulation. The carrier wave then carries the signal the long distance to the radio receiver. The receiver amplifies the signal from its antenna, selects and tunes the station, demodulates the carrier back into a sound signal, amplifies it, and sends it to a speaker to be translated back into sound.

FM stands for Frequency Modulation. In FM radio, the audio signals are imposed upon the carrier waves using frequency modulation. This means that the instantaneous frequency of the high frequency carrier wave (88,100,000 Hertz – cycles per second) is altered (modulated) by the instantaneous value of the audio signal. In AM radio, it is the amplitude of the carrier signal that is modulated. FM is like opera singing: the modulation of the 88.1 MHz carrier wave by the audio signal is analogous to the vibrato of an opera singer. The opera singer modulates his or her pitch (frequency) by a slowly varying signal called the vibrato. The singer’s voice is broadcast throughout the concert hall. Your ear picks up the sound of the singer like an antenna picks up a radio wave. Your brain tunes in and demodulates the signal like an FM radio, and you perceive the vibrato.

PART B: HOW WKNC OPERATES

WKNC is a business, and our business is having fun while sounding good on the air. Although that may sound simple, it isn’t. It requires business sense, responsibility, preparation and lots of practice. Being an announcer isn’t brain surgery, but creating “good” radio does involve study of FCC rules and regulations, memorization of mechanical operations, and the ability to do many different tasks simultaneously.

The term “radio” can be applied to many different kinds of radio stations – terrestrial (meaning land-based), Internet, satellite and digital HD radio. WKNC is a terrestrial station that simulcasts its programming using an Internet stream. There are two categories of terrestrial radio stations: commercial and non-commercial. Although the FCC makes this classification, both stations are businesses with the difference being in how they make their money. Commercial stations are located on the FM dial at frequencies above 92.1 and are allowed to sell advertisements or commercials, charging businesses money in exchange for air time. Many of these stations are owned by large corporations like Clear Channel or Infinity Broadcasting that own multiple stations and are interested in having many listeners.

These stations charge heavily to run commercials so that they can exceed the operating costs of running each station, pay its staff and generate a profit so the broadcast group can stay in business. Commercial stations are allowed to make a profit by broadcasting. On the other hand, it is illegal for non-commercial stations to make a profit; non-commercial means non-profit.

The FCC defines them as “educational or non-commercial” stations, and their purpose is simply to serve the public without having to worry about catering to advertisers who have a vested interest in what is broadcast. They still need to make money, but only enough to offset what they spend. Although many commercial stations can afford “high profile” marketing to capture loyal listeners, many non-commercial stations that feature the syndicated National Public Radio (NPR) network, other educationally-oriented or alternative programming remain extremely popular. Non-commercial stations have three different methods of making money to cover their operating expenses, and may use any combination of these resources:

1. They are allowed to sell what’s called “underwriting” which involves a trade of money for air time, but with strict limitations on the length and content of such announcements.
2. They are allowed to have fund raisers or “radio-thons” in which they solicit listeners who particularly enjoy their programming to donate money to support the station.
3. They are partially or fully subsidized by a sponsor institution, such as the university that holds its license.

WKNC is a non-commercial station, located on the FM band at 88.1 MHz. We are not owned by a large broadcast group but by North Carolina State University and its Board of Trustees. As the licensee of WKNC-FM, the Board of Trustees of North Carolina State University is responsible for all programming and operational decisions at the station. The Board allows the student staff to make day-to-day programming and personnel decisions and to choose music and other content within the guidelines agreed to and published in this manual. The Board can, however, make broad policy decisions. They are allowed to make whatever decisions about the station they choose within their authority as the licensee of a station at a public institution of higher education. To ensure the station is operating according to its charter, WKNC is divided into departments responsible for specific aspects of the station’s operation. Each of these departments is supervised by a department director. The station’s Board of Directors is charged with meeting regularly to determine station policies, plan promotional events and keep the station running smoothly.

Surprisingly, most of the work required to make radio happen occurs outside of the control room. Of course what happens inside the control room is the most exposed and hence the most critical aspect of the station’s operation, but it is for this reason that the work done by the engineering, programming, production, promotions and music departments to prepare material broadcast is of paramount importance. In other words, what goes out over the airwaves should be thought of as the finished product of a large group working together rather than just the work of one announcer. An announcer can only be as good as the station for which he or she works.

A staff of the most dynamic announcers in the world does not make a radio station. Without a programming staff to determine the sound of the radio station; without a production staff to create that sound; without a promotions staff to develop exciting ways of getting the public’s attention; without a music staff that knows what’s hot and what’s not; without an engineering staff that knows how to maintain and effectively operate all the equipment which make the “magic” happen, announcers are powerless. This is true for commercial and non-commercial stations on the AM or FM band. Teamwork counts!

GETTING STARTED

Operating a 25,000 watt FM radio station is not easy. It is much more than just spinning records or CDs and being cool when talking on the radio. A good show requires careful planning so the music is arranged and played in a way that is enjoyable to the listeners, breaks are made when scheduled on the program log, and rules are followed as determined by station management and the FCC. Meter readings must be taken regularly, logs must be filled out accurately, and breaks should be relevant, interesting, crisp and to the point. Anything short of trying your best to follow this example is not acceptable. These guidelines are not to keep you from having fun while on the air, but to protect you as an announcer from breaking station policy.

The only way all of these things can be mastered is through careful training and practice. Anyone who thinks knowing how to run the board is all it takes is mistaken. Anyone running the board without training is breaking station policy. Anyone allowing an untrained operator to broadcast on our frequency is subject to suspension or dismissal. This is why WKNC does not allow anyone to be scheduled for a DJ shift without successfully completing the training process.