Thank you all, the term yaw stabs may have slipped in from a past on V bombers, sorry, I did of course mean Yaw Damper. I'm rather constrained to the B737 as it is the model used to illustrate Autoflight in the ATPL syllabus. I have done a you tube trawl but surprisingly there doesn't seem to be much illustrating this. Knowing that the max rudder limiter deflection in the high altitude cruise is 5 deg is particularly useful.
I think may well illustrate an induced oscillation, lightly damped with the yaw damper out then recovering rapidly with the yaw damper selected on.