Telemetry is made up of a series of people, parts, and events that allow for data to be collected from a long distance. Long distance is the key to that statement, which means that information needs to be sent somewhere. That job belongs to a telemetry transmitter. What exactly is a telemetry transmitter? It can actually be a number of things. It might be a satellite signaler, it could be a radio transmitter, or it could even be a digital transmitter. As long as it is sending telemetry information it can be called a transmitter.
One example of how telemetry transmitters may be used is to track whales. The migration of whales would be difficult to track if scientists had to dive in the ocean and follow them. Wit telemetry they can sit in a control station and receive data on where the whales are located from a satellite. How does the satellite get it? A telemetry transmitter is affixed to the whale and sends a signal up to tell it where the whale is. Without the telemetry transmitter, the data is not received. Without it, the whale would have to be found again and the piece removed to get the data out.
Telemetry transmitters are not just used to track wildlife, though. They are also used in the care of astronauts in space and in tracking marketing data through vending machines. Any time data has to be collected and it is not on-site, that data needs to be transmitted in some way.
Transmitters are a valuable part of telemetry. In turn, telemetry is a valuable part of data collection in most every large field. The information has to get from point A to point B somehow and a transmitter makes that trip much quicker and much more efficient than ever before.