If you're able to shed any light on who created this clock, when, where or why, please do get in touch. Leave a comment on my blog or email me.
At present I have no documentation for this clock, and it has no markings other than the labels for the controls and external connections, such as "LPS OFF", meaning lamps off, "RESET", meaning set the time, etc. Internally it is evidently hand built, with a few of the parts being obviously hand made but most being telephone exchange components. The lamp array is cut from ebonite and the offcuts used as brackets. The standard of construction is extremely high, as good as that seen in high quality test equipment and high end consumer electronics of the period, which I reckon to be mid 1940s, perhaps a little later.
The clock relies almost entirely on electro mechanical switches. The time source is a drop in "module" comprising a 240V 50cps synchronous electric motor with gearbox giving one RPM. Attached to this is a cam which activates a switch that looks to have been taken from a relay similar to those used elsewhere in the clock. This gives one pulse per minute.
The rest of the mechanism is built from relays and uniselectors and counts minutes, tens of minutes and hours. These are displayed in two rows of lamps, the top row being hours (1 to 12) the first five lamps of the second row being tens of minutes and the remaining ten lamps being minutes (0 to 9).
Uniselectors are also known as stepping switches and stepping relays. In telephone exchanges this type of switch is used in a 2D arrangement known as a Strowger switch.
Mechatronics, see Mechatronics - Wikipedia. Maybe I should call this artefact a "Mechatronic Clock".
Electric clocks (1930-1950)