Quite an interesting article her on the inventor of the first digital clock. https://www.bbc.co.uk/news/uk-england-humber-46252838 Image captionThomas Bromley's Digitron Electric Clock was built in his shed at his Hull home in 1961 One of the world's first digital clocks, which was made by a man in his shed, has been sold at auction. Thomas Bromley, an engineer and amateur inventor, created his Digitron Electric Clock in 1961 at his home in Hull. He held the patent to the design for three years but chose not to renew it - potentially costing him millions of pounds. The prototype was sold for £460 to a UK buyer when it went under the hammer in Beverley, East Yorkshire. Image copyrightBROMLEY FAMILY Image captionBromley, who died in 1990, was an electrical engineer by day and an inventor by night Auctioneer John Hawley said Bromley had received an award at the Salon des Inventors in Brussels in 1964 for his prototype and would have been a multimillionaire had he renewed his patent. A year after the patent ran out, the Japanese started manufacturing "virtually an identical clock and sold it in many thousands", he said. 'Mad professor' Bromley's son, David, said the inventor received a commercial order to "make 20 by Christmas but he didn't have the facility to start manufacturing them". Speaking after the auction, Mr Bromley said he was a bit sad to part with the timepiece. "It was always in the cupboard in my mother's house. She died a couple of months ago and me and my sister felt we just wanted closure." Image captionBromley missed out on commercial success and this digital clock, which went under the hammer, is the only one he produced Remembering how his father was "an electrical engineer by day and an inventor by night", Mr Bromley described how he was "always in his shed". "He'd come out at nine or 10 o'clock at night. He was like a mad professor in there. "I used to go in there and sit and watch. He had all sorts of equipment and gadgets. That was his life." Bromley, who died in 1990, also invented curtains that automatically closed when the sun went down.
Interesting that Google shows absolutely nothing about this except that BBC article. I can't even find one of the Japanese clocks they mention in anything - there is a D.E Protzmann that is mentioned as having a patent on the first digital alarm clock in 1956 (likely flipper card style) but I can find no pictures of it, and if you look for vintage nixie clocks good luck wading through all the modern implementations of them. Here's my Nixie clock. I'm not sure where it is currently. I packed it away safely when I moved 4 years ago and havent' seen it since.