Andrew wrote:
ATC says "radar contact, 20 miles south of XYZ, proceed on course". Do
you acknowledge this transmission? How about when ATC says "altimeter
setting 2992" on your first contact after a handoff? Does this require
acknowledgement?

Dunno about required, but I acknowledge both.

In the past, I've acknowledged such things if the controller was not
busy.

I acknowledge with my N-number only. They'd have to be *real* busy for that to
cause trouble.

George Patterson
There's plenty of room for all of God's creatures. Right next to the
mashed potatoes.