They are interchangeable, but S-Video cables make very good ADB Cables and ADB Cables make very poor S-Video Cables.
The shell on any cable is invariably grounded, it's not connected to the ground lines at the signal level because it's connected to the RFI shielding of the Computer. The signal level lines are for clean ground level connections and the Logic boards are connected to the RFI shielding at specific points that are designed into the PCBs where RFI won't be problematic.
The requirements for RFI shielding for ADB signals are paltry as compared to video signals, there are huge differences in the frequencies involved to be shielded from the environment for FCC approvals and for signal integrity within the cable. ADB is duck soup, S-Video ain't.
The above is my understanding of the situation, BTW, not a statement of fact.
The shell on any cable is invariably grounded, it's not connected to the ground lines at the signal level because it's connected to the RFI shielding of the Computer. The signal level lines are for clean ground level connections and the Logic boards are connected to the RFI shielding at specific points that are designed into the PCBs where RFI won't be problematic.
The requirements for RFI shielding for ADB signals are paltry as compared to video signals, there are huge differences in the frequencies involved to be shielded from the environment for FCC approvals and for signal integrity within the cable. ADB is duck soup, S-Video ain't.
The above is my understanding of the situation, BTW, not a statement of fact.