The DBT-700 is from 1986, and has a nice large screen, notable for its unusual full-size seconds, in a compact metal and glass case. Unusually, it does the higher beep upon returning to time mode, but won’t jump straight there from a mode that’s just been used. Designed to store train timetables (feature listed here as schedule) in addition to its databank functionality, but unfortunately the manual for this one is lost in the mists of time, so an ideal gift for someone who enjoys puzzles. This titanium nitride plated example has some unsightly wear on the front buttons, a bit of corrosion flaking the plating around the back, and an aftermarket bracelet, so is priced accordingly.