[R-390] OT: Ramp Generator

[Barry]

Hopefully this isn't too dumb of a question, but I was wondering how ramp (sawtooth) generators work and started looking at some basic schematics and videos.  From what I saw, it appears that to produce the ramp, a capacitor is charged through a resistor and the voltage at the RC point is the ramp voltage.

This is confusing to me.  Capacitors don't charge linearly, do they, and, if that's true, then why is the ramp linear wrt time?

Sorry for the OT and dumb question, but I really don't understand this and knew that the smart fellars on this list can set me straight on it.

Thanks,
Barry - N4BUQ