The UMSA allows you to connect your computer to a CRT television via a SCART socket.
This product does not do 'down scalling', it is up to your computer to provide a 15Khz signal.
For this you can use the Calimity or WinModelines drivers for example.
For the audio part, 2 RCA sockets to be connected to the source allow the signal to be injected into the SCART socket.