My first PAL TV, bought circa 1993, Sharp, was unable to display NTSC or 60hz video, the image would be out of sync, even using an RGB SCART cable. My second one, Sony Trinitron bough in 1999, would display NTSC 60hz in black and white using a composite cable, but full color using a RGB SCART.
This was most noticeable when using my modded PAL PSX, as NTSC games would display in NTSC 60hz, therefore my first TV couldn't play them, only the second (one of the reasons I bought it). However, in my modded PAL Saturn, all games, even NTSC ones, would display in 50hz, so I could play them in the first TV, with thick horizontal black bars. The PAL Saturn was supposed to be able to be modded for 60hz, though.