Seiko 6139-6020 "Doc Chrono" aka "Pulsations", September 1969
This is an early example of the so-called Pulsations or Doc Chrono. These were made with an internal rotating ring that was for counting pulses, rather than calculating speed.
The watch is an original survivor. It shows wear, but no abuse. I just fully serviced it, and replaced several major components, as well as upgraded the movement. I also installed a genuine new-old-stock dial.
6139A movement fully and freshly serviced
Lower mainspring arbor jewel installed
Train bridge replaced with NOS
Case fully rebuilt with all new seals
Crystal replaced with new 350T02ANS
Dial is an NOS replacement, never installed. It had some patina from storage, but as a result it matches the rest of the watch.
Both chronograph hands are original to this watch and have been slightly touched up
All lume is original. Hand lume is patina’d in towards the hand stack.
Case in original polish. Case has not been touched up or improved. This is a daily driver watch.
Pulsations indicator ring / rotating ring has lovely undamaged text and the original lume pip - the pips on these often go missing.