Transmission

Large television stations usually have some sort of television studio, which on major-network stations is often used for newscasts or other local programming. There is usually a news department, where journalists gather information. There is also a section where electronic news gathering operations are based, receiving remote broadcasts via remote pickup unit or satellite TV. Vans, trucks, or SUVs with this equipment are sent out with reporters, who may also bring back news stories on videotape rather than sending them back live.
Weather is also a significant part of the station. Stations with newscasts also have their own meteorologists and Doppler weather radar, and produce their own forecasts, which often vary from station to station. In the U.S., most NBC stations now carry Weather Plus on a second digital channel, which mixes national and local segments.
Stations not affiliated with major networks generally do not produce news or weather, or much other programming. Some stations (known as repeaters or translators) only simulcast another, usually the programs seen on its owner's flagship station, and have no production facilities of their own. This is common in most countries outside of the U.S., Canada, U.K. and Australia. Low-power stations typically also fall into this category worldwide.
Most stations which are not simulcast produce their own station identifications, using digital TV graphics. TV stations may also advertise on or provide weather (or news) services to local radio stations, particularly co-owned sister stations. This may be a barter in some cases.
As with other stations, the radio antenna is often located on a summit, the top of a high skyscraper, or on a tall radio tower. A studio/transmitter link (STL), via either radio or T1/E1, is used to get the signal there. A transmitter/studio link (TSL) may also send telemetry back to the station, but this may be embedded in subcarriers of the main broadcast. Stations which retransmit or simulcast another may simply pick-up that station, over-the-air or via STL or satellite. The license usually specifies which other station is it allowed to carry.
VHF stations often have very tall antennas due to their long wavelength, but require much less effective radiated power (ERP), and therefore use much less transmitter power output, also saving on the electricity bill and emergency backup generators . In North America, full-power stations on band I (channels 2 to 6) are generally limited to 100 kW analog video (VSB) and 10 kW analog audio (FM), or 20 kW digital (8VSB) ERP. Stations on band III (channels 7 to 13) can go up by 5dB(W) to 316 kW video, 31.6 kW audio, or 63.2 kW digital. Low-VHF stations are often subject to long-distance reception just as with FM. There are no stations on channel 1.
UHF, by comparison, has a much shorter wavelength, and thus requires a shorter antenna, but also higher power. North American stations can go up to 5000 kW ERP for video and 500 kW audio, or 1000 kW digital. Low channels travel further than high ones at the same power, but UHF does not suffer from as much electromagnetic interference and background "noise" as VHF, making it much more desirable for TV. Despite this, in the U.S., the FCC is taking another large portion of this band (channels 52 to 69) away, in contrast to the rest of the world, which has been taking VHF instead. This means that some stations left on VHF will be harder to receive after the analog shutdown. Since at least 1974, there are no stations on channel 37 in North America for radioastronomy purposes.