Best tools to calibrate TT motor actual speed?


A fellow member, Lewm , was kind enough to sell me his old Walker motor controller for my Nottingham Analogue TT.
It is in good working order but now I find I need to acquire a method ,or tools may be best phrase , to calibrate my TT motor speed exactly.
Never having any adjustments available for TT motor speed it is not something I had given any thought to.

Lewm did mention a KAB strobe which uses a disc and a battery powered strobe.
Also a quick perusal reveals various manufacturers of marked platter discs where you would use a mains powered light ( to establish 60hz I assume) to check actual speed.
What does anybody here use or has used in the past that is easy, reliable, accurate and fairly priced?
Thank you
128x128uberwaltz
What a wonderful hobby we share with some of the best people you could ever wish to meet.
Turns out that drrsutliff lives about 1 mile away on the street that my house is on the corner of at next junction!
He very kindly brought his KAB round last night for me to check TT speeds and left me with it as he was off to a conference in South Florida for 4 days.

Very refreshing to find there still ate some very decent people out there and to find there are fellow audiophiles on the doorstep!

Thank you again and have a safe trip.
I use Clearaudios disc and strobe the disc has grooves on it and you would not believe the drag of the stylus has on the speed unless  you see it first hand