RE1802 3 base router speeds

[drunkcat]

This router is rated from 15,000-25,000 RPM. The variable speed dial if labeled A-F and Ryobi does not tell you what speeds the letters correspond to. I would guess they are evenly spaced so:
A 15k
B 17
C 19
D 21
E 23
F 25
I wrote Ryobi Tech support to verify and they responded that "individual RPM values are not available."

Is there some reason why their wouldn't be a linear progression with each value on the variable speed? I would like to know what RPM I am running at with various sized bits.

Anyone?
Scott

[LarryG]

My Makita router is similar. I think it's reasonable to assume the "steps" between the letters are approximately equal, because (a) I can't think of any good reason to design the electronics so that they were NOT approximately equal, and (2) if there WAS a good reason to make them unequal, what would be the point of doing it that way if you're not going to let the consumer in on the secret?

A variable control of this general type does not necessarily have to be linear, but my guess is that this one is.