STS or Space Transportation System is another name for the space shuttle program. The shuttle program was started back in the early 70's and the first space shuttle mission (STS-1) was launched in 1981. On Wikipedia you can read more about the many missions and the space shuttle.
The main goal (for me) has always been to record the space shuttle. As the space shuttle ascend from the Kennedy Space Center in Florida it crosses the atlantic ocean. Roughly 20 minutes after liftoff it is possible for us Europeans to pick it up on our receivers. The shuttle has two UHF frequencies it can use. The primary frequency is 296.800 MHz and 259.700 MHz is the secondary frequency both AM modulated. (For EVA it has a third frequency 279.000 MHz)
An element of luck is also needed when listening to the space shuttle. Because it travels very fast and it passes over the netherlands it is only possible to hear it for a short time. Here in Denmark the shuttle only just passes over the horizon. So you have to pray for the astronauts to actually say something on the radio at this moment. Usually they do. For some reason they have a lot to talk about with ground control.
When the shuttle reaches space it turns over and open the payload bay doors. A small Ku-band antenna inside the payload bay is deployed. Now they switch from UHF to Ku-band which means no more listening in for us nerds. From there on all communication is done through TDRS satellites.
As the shuttle prepare its return to earth there is again an opportunity to hear it. In the deorbit phase which is the last 2-3 trips around the earth it transmit on UHF again. On these last trips around the earth there is a good chance of picking up something.
Below are the recordings I have made since I started out in 2007.