I thought I had seen all the Sansui decoders (and luckily own the "big 3"), but I have never even heard about this early unit:
https://www.ebay.com/itm/2038983411...66&osub=-1~1&crd=20230912150154&segname=11304
https://www.ebay.com/itm/2038983411...66&osub=-1~1&crd=20230912150154&segname=11304