Stan Griffiths (Dec 19, 1938 – Jan 29, 2020) was employed at Tektronix from 1960-1966 and 1970-1989.
For some period, Stan was one of the proprietors of a scope calibration business called Mobilscope. They built a mobile scope calibration lab in a trailer. Companies who employed the services of Mobilscope could have their scopes serviced with fast turnaround time and no shipping hassle.
Stan owned a large collection of Tektronix equipment and ran a Tek related website (now defunct, partial archive at http://web.archive.org/web/20170924050812/http:/www.reprise.com/ash/clients2/default.asp)
He wrote a book, Oscilloscopes: Selecting and Restoring a Classic, covering 300- and 500-series oscilloscopes and plug-ins, and early 400-series (410, 422, 453/454 and 491 spectrum analyzer).
Mobilscope cal sticker on 422 seen on Ebay in January 2021