Restoring HP’s atomic clock that sync'ed the world

We restore an HP 115BR divider and clock. Its atomic-driven 1 second tick famously sync'ed the world's second in 1964.

HP 115BR option H27 Reverse Engineering.pdf My lab book notes with the reverse engineered details of our HP modified/upgraded/undocumented option H27 unit. Adobe Portable Document Format - 4.39 MB - 07/17/2025 at 05:03		Preview

HP 115BR Frequency Divider and Clock Op and Service Manual 1967.pdf HP Manual for the HP 115BR. Includes the schematic of the standard unit. Adobe Portable Document Format - 3.65 MB - 07/17/2025 at 05:02		Preview