Circuit & Information on TOSLINK interface
So you want to get a high quality audio for minidisc recording but when using red and white RCA, the quality drop drastically. Here a my cheap solution for you. Actually you can find a lot of references of this type of simple project in the internet.
* S/PDIF = Sony/Philips Digital Interface
* TOSLINK = ( TOSLINK Interconnect History & Basics )
* Another web offering the same information
* SPDIF at epanorama.net
Meet my version of cheap, 2 components TOSLINK @ S/PDIF. Try to find a cable with connector from old PC casing for this. (HDD led,reset switch or power button connector)
Assemble it using your own creativity. Use the pen tube for the light transmission.
Connect it to the back of your CDROM drive. Since (D, the signal should go to anode and G should go to the ground/cathode)
Test it out. you should see the light come out from the tip/tube.
Connect to your MD or other device such as power amp that support optical in.
Actually, I have one of this (USB to SPDIF converter) for my minidisc but just to share with you on how to find a supercheap solution before start buying. :-)
Even my new MSI mainboard do have built-in TOSLINK :-)