[doctor]

While searching for slightly different stuff, I came across a site that sells video converters of several kinds; PAL to NTSC, CGA to VGA, RGB to SECAM and almost any combination you can want. They also have other products and some power converters. Perhaps their prices are outrageous, but at least it is a hint which kind of products that exist. Many products are loose boards meant for industrial use.

[sumone]

So there must be something wrong with them since you posted in Hardware Troubleshooting.

Thanks for the recommendation of not to pursue these defective hardware items!