Constant speed prop question

On 2008-07-20, Steven P. McNicoll wrote:
Terence Wilson wrote:
I found this paragraph to be confusing because it makes several
references to rpm but doesn't clarify whether it is engine or prop
rpm. The blanks were inserted by me. Can someone help me out?
It's engine rpm, but in direct drive engines prop rpm and engine rpm are the
same.

....and in geared engines, or engines with some other propeller speed
reduction unit (such as the Rotax 912), they're directly proportional. Thus,
it doesn't matter whether it's engine or prop rpm.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (FRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC (got it!)

Jay Maynard wrote:
...and in geared engines, or engines with some other propeller speed
reduction unit (such as the Rotax 912), they're directly proportional. Thus,
it doesn't matter whether it's engine or prop rpm.

Yes, unless there is a torque converter between the crank and the prop.