How does a TV station work?

A news studio looks big on TV but is often a modest room: a desk, a backdrop, and three or four studio cameras on heavy wheeled pedestals. A camera operator glides each one and a column of gas springs lets it rise and fall smoothly.

How does the anchor read the news without notes? The teleprompter. A monitor lies face up under the lens, showing the script mirror-reversed. Above it sits a sheet of half-silvered glass at 45°. The anchor sees the monitor's reflection, now the right way round, floating over the lens. The camera looks straight through the glass and never sees the words. So she can read and look you in the eye at the same time.

Overhead, a lighting grid holds soft LED panels in the classic three-point pattern: a key light in front and to one side, a gentler fill on the other side, and a back light that puts a rim on hair and shoulders so the anchor stands out from the backdrop.

In the corner is a chroma key wall painted one pure green. A computer replaces every pixel that is "green enough" with a weather map, so the presenter seems to stand in front of it. Wear green and you vanish too. Finally, the anchor wears an IFB earpiece so the producer in the control room can talk to her while she is live.

Behind the studio is the production control room (PCR), which British and Indian crews call the gallery. It is dark and quiet, and one wall is a multiviewer: a big screen split into boxes showing every source at once, all three cameras, the VT (recorded video) and the graphics.

Two boxes matter most. Programme (PGM, red) is what is on air right now. Preview (PVW, green) is the shot waiting to go next. The vision mixer selects the next source on the preview bus, and on the director's word presses CUT (an instant change, one frame, 1/25 of a second) or MIX (a gentle dissolve). Preview and programme then swap.

A red tally light glows on top of the camera that is on air, so the presenter knows which lens to look into and the camera operator knows not to move. Names and titles (lower thirds) and the channel logo are laid on top by a downstream keyer, after the mixer, so they stay put through every cut.

Everyone wears a headset. The director calls shots over talkback, the producer watches the clock and talks in the anchor's ear, and the graphics and audio operators sit alongside. Before a report plays, the director counts down: "Roll VT… three, two, one, take VT."

For a live report from far away, a channel sends an OB van (outside broadcast) or a smaller DSNG van: digital satellite news gathering. The camera's picture is compressed by an encoder and beamed up from the roof dish to a geostationary satellite, which circles the equator once a day and so seems to hang still in the sky. The satellite beams it back down to the channel's teleport, a yard of big dishes near the studio.

That is a long way. The satellite is 35,786 km above the equator, and from India it is even further because you look at it at a slant. Up and down again is over 72,000 km. Even at the speed of light that takes about a quarter of a second (0.24 s or more) for one hop. The anchor's question takes one hop to reach the reporter, and her answer takes another hop back. Add the time the encoder and decoder need, and you get the famous awkward pause.

Today many reporters carry a bonded cellular backpack instead: an encoder with several 4G/5G modems, each with its own SIM. It chops the video into packets, sends them over all the networks at once, and a server at the studio puts them back in order. If one network gets crowded, the others carry more. It needs a small buffer to wait for late packets, so it has a delay too, usually around a second.

Inside the station, pictures travel uncompressed on thick SDI cables. A single HD camera sends 1920 × 1080 pixels, 25 frames a second, with two 10-bit samples per pixel (brightness plus half-resolution colour, called 4:2:2). That is about 1 billion bits a second of picture, and the cable standard, HD-SDI, runs at 1.485 Gbit/s. No satellite channel or home connection could carry that for hundreds of channels.

So before a channel leaves the building, an encoder squeezes it with a codec: MPEG-2 (from 1995, still used on many free channels), H.264 (2003) or HEVC (2013), each needing about half the bits of the one before. Two tricks do most of the work. Each I-frame is cut into 8 × 8 blocks, turned into patterns by a maths step called the DCT, and the fine detail is rounded off. P-frames say "this block moved 3 pixels left" and send only the small difference. B-frames can borrow from the frame before and the frame after. A run from one I-frame to the next is a GOP.

The finished channel is run by a playout server. It follows the schedule to the second: live news, then an ad break, a promo, the channel ID, and the next serial from its hard drives, with the logo laid on top. It writes an as-run log, the proof sent to advertisers that their ad really played. (For years Indian rules capped ads at 12 minutes in a clock hour; the government removed that cap in August 2026.)

The finished channel leaves the teleport on a big dish pointed at a satellite such as GSAT-15, which hangs over the equator at 93.5° E and carries DD Free Dish. The satellite's transponders receive on one frequency and send back down on another, over the whole of India at once.

There are two main satellite bands. Ku band (about 11–12 GHz, waves 2.6 cm long) works with the small 60 cm dishes on Indian rooftops, but heavy monsoon rain soaks it up: this is rain fade, when your DTH picture freezes in a storm. C band (about 4 GHz, waves 7.5 cm long) barely notices rain, but needs dishes 2–3 m across, so cable operators use it.

At the focus of a dish sits the LNB (low-noise block): it amplifies the faint signal and shifts it down to about 1–2 GHz so it can run down a cable to the set-top box. Cable homes get channels from a headend via their MSO and LCO. Some homes still use Doordarshan's terrestrial towers, and more and more people watch OTT streams over the internet.

What you pay is set by TRAI's New Tariff Order (2017, in force from 2019): each pay channel has a declared monthly price, you pick channels or packs, and your operator adds a network capacity fee. From 2020 that fee was capped at ₹130 for 200 channels; TRAI removed the cap in 2024.

Most TV channels are paid for by advertising, and advertisers pay by how many people watch. Nobody can count every home, so a ratings agency picks a panel: a sample of homes chosen to look like the country in miniature, each with a people meter. In India this is BARC (Broadcast Audience Research Council), whose BAR-O-meters listen for an inaudible audio watermark each channel hides in its sound. BARC's panel grew from about 11,000 meters in 2015 to about 55,000 by 2023. The TRP (television rating point) figures that come out steer crores of rupees of ads.

A sample is not the whole town, so every rating has an error bar. Big samples give small error bars. But ratings are often sliced thin, "one city, weekday afternoon", and then only a handful of meter homes are watching, and the error bars balloon. That is also why meter homes are kept secret: if someone paid a few of them to leave a channel on, its rating would jump. India has seen police cases alleging exactly this (2020).

News has rules too. Channels must follow the government's Programme Code under the Cable Television Networks Rules. Complaints about news channels can go to the NBDSA (News Broadcasting and Digital Standards Authority), a self-regulatory body led by a retired judge, which can order corrections, apologies or fines. Good newsrooms fact-check: confirm with two independent sources, trace a video to its first upload, check the date and place, and correct mistakes on air.