Cast your minds back to the depths of time to when you may have had laserdisc players. Well instead of a dolby digital output these had an AC3 RF analog output. Once demodulated this provides the 5.1 DD output (like a DVD player).

I'm after either a AC3 RF demodulator (preferred) or a 90's era DD decoder that still has the AC3 RF input.
I guess the other option is a Laserdisc player that has optical Digital output (some of the later ones had this)

Anyone got anything that they can part with cheaply?