Local insertion
 |
In broadcasting, local insertion is the act or capability of a broadcast television station, radio station, or cable TV system to insert or replace part of a broadcast network feed with content unique to the local station or system. Most often this is a station identification (required by the broadcasting authority), but is also commonly a television commercial or sometimes a radio ad, or a traffic or weather report. A digital on-screen graphic ("dog" or "bug"), commonly a semi-transparent watermark, may also be keyed (superimposed) with a TV station's logo over the network video using a character generator and genlock.
Automated local insertion used to be triggered with in-band signaling, such as DTMF tones or sub-audible sounds (such as 25Hz), but is now done with out-of-band signaling, such as analog signal subcarriers via communications satellite, or now more commonly via digital signals. Broadcast automation equipment can then handle these automatically.[citation needed] In an emergency, such as severe weather, local insertion may also occur instantly through command from another network or other source, such as the Emergency Alert System. In this case, the most urgent warnings messages may interrupt without delay, while others may be worked into a normal break in programming within 15 minutes of their initial issuance.[citation needed]
Local insertion within individual programs
In the United States, insertion can easily be heard every evening on Delilah, a nationally-syndicated radio show, where the host does a pre-recorded station-specific voiceover played over a music bed from the network. When she says "this is Delilah", her voice (often in a slightly different tone or mood than what she has just been speaking) then says "on B98.5 FM" when heard on WSB-FM in metro Atlanta, for example. Listeners to other stations hear their own station's moniker or ID instead. Because of this slight difference in vocal quality, many syndicated radio networks suggest using only one voice for local station ID 24/7; in this way, the difference in vocal intonation is lessened. Whether or not this has an effect on the actual listener is not known, as it appears many radio listeners are still under the impression that talent waits in the Green Room until it is time for them to read their commercials live.
Local commercial (and some non-commercial) over-the-air television stations also locally insert local promo breaks during each half-hour of network programming. Broadcast television networks give their affiliates either 60, 90 or 120 seconds each half-hour (typically totaling about four minutes each hour) to run local station breaks, including station promos (and on a few stations, local news updates, current time and temperature information or a brief local weather forecast), over network programming. Typically, these networks air a blank feed showing the network's logo (such as with Fox and NBC) or a series of public service announcements (as with ABC and CBS) while stations air local promos. PBS member stations also insert promos for PBS network series and locally-produced programming during promo breaks, as PBS is non-commercial the network typically does not feature breaks during the programs themselves, instead promos are insterted in-between programs, even if the member station is carrying PBS' national network feed.
Various TV morning shows, such as Good Morning America and The Today Show, also have a local news break for five minutes (sometimes as little as three minutes) prior to each "top" or "bottom" half-hour (:25 to :30 and :55 to :00), though the national feed continues for stations that do not wish to "break away", either because they have no news operation or because they may not air a morning newscast (e.g., NBC affiliate KTEN in Ada, Oklahoma does not air news cut-ins during the weekend edition of Today as the only weekend newscast on that station airs at 10 p.m., but cut-ins are shown during the weekday telecasts where Today follows a morning newscast). This also occurs with news on National Public Radio's Morning Edition and All Things Considered, which are on during the morning and evening rush hours, respectively.
Local insertion is also used by cable television and telco providers, in which cable and telco headends insert advertisements for the cable system, promos for programs on other cable channels carried by the cable provider and commercials for local area businesses (e.g., car dealerships, furniture stores, etc.) at least twice each hour; unlike most commercial broadcast stations, however, cable channels often run only 60 seconds of local commercial inserts each half-hour near the end of the first or second commercial break and are aired in place of national ads or network promos that air during that given time. Direct-broadcast satellite services do not locally insert content during commercial breaks, so viewers are able to see ads or promos that are covered up by the local content on cable.
Local insertion on cable television is used especially on The Weather Channel in the U.S. and The Weather Network/MétéoMédia in Canada, where systems like the WeatherSTAR and IntelliSTAR have been used to show local forecasts (known as "Local on the 8s" on The Weather Channel in the U.S.) every ten minutes, and well as the Lower Display Line (LDL) graphic that is shown at other times. The Weather Channel, in particular also airs barker ads during national breaks at the end of some commercials allowing its WeatherSTAR or IntelliSTAR systems to insert certain area locations for certain businesses, such as restaurants or auto rental dealers; though The Weather Channel has not done this as much in recent years as they have in the past. This only applies to the cable systems, although in the U.S. direct-broadcast satellite services show an LDL of the current conditions and 12-hour forecast for select major cities. This is not seen on older TVRO or "big ugly dish" systems, as this is intended as a backhaul and has very few end-users, and is used as a clean feed. Starting in the early 2000s, some cable systems began carrying a local insert called "Local Edition", a segment featuring local news inserts (which are produced by area television stations or local cable operators) that air at :24 and :54 minutes past the hour during HLN's rolling daytime news block.
Transmitter identification
Broadcast translators may also have local insertion, though this is very limited to identifying the repeating station's callsign and community of license separate from its parent station. In the U.S., the Federal Communications Commission (FCC) also allows up to 30 seconds per hour for fundraising to keep the translator service on the air.