The defaults it gives me are 180 lines, so if this were a real single turn spiral nipkow disk, then for the image to appear at the 3 inches wide it does on my screen (no magnification), the disk would have to be about 14 feet (4.3 meters) in diameter!

And at 1500 RPM no less.

"Don't sit too close to the television, Timmy, it might cut off your arm."

As best I can tell, the 180 line system was used with CRTs: https://en.wikipedia.org/wiki/180-line_television_system