Preheat-start ballasts exist which have integral starters. This means they have the typical four wires of an RS or TS ballast, but the characteristics of a preheat ballast. This seems to be more common for circline lamps for some reason. Here is a schematic I drew of what is likely inside these:
https://www.lighting-gallery.net/gallery/displayimage.php?album=lastup&cat=0&pos=0&pid=265862Glow starters go bad. So much so that manufacturers felt the need to integrate them into the bases of some single-ended fluorescents to make replacement more simple. Because they go bad, they should be easily replaceable. This is usually facilitated by a socket that is accessible without fixture disassembly. So what did they choose to do with these integral-starter "self-start" ballasts? They potted the starter in tar, inside of a non-accessible component that is supposed to be a non-consumable, the ballast.
Great idea.
I get that it is for space-saving purposes, especially for circline fixtures. But why didn't they just integrate the starter into the base of the circline lamp? What is the point of this buffoonery?