Generally, devices that send a digital signal, such as DVD players or video game systems, send their signals over an RCA cable. However, if you have a device with RCA ports that you need to connect to a television (or computer) with a USB port, you can convert your signal easily by creating a makeshift adapter cable.
Connect one end of your RCA cable to the RCA ports on your digital device.
Connect the other end of the RCA cable to the RCA ports on your RCA-to-USB adapter.
Connect the USB end of the RCA-to-USB adapter to an available USB port on your television or computer. You will now be able to convert your audio signal to digital through the completed data cable.