Seiko 6139 6020 Chronograph

erpin9 · Jan 4, 2018

I managed to snag another Seiko in pristine condition, a pulsation chronograph with ref. 6139 6020. This watch has a near perfect gloss silver dial with black outer pulsation ring. The case and bracelet are also in good unpolished condition. This one looks like another drawer queen based on its overall condition.

Foo2rama · Jan 4, 2018

Never seen one with a pulsation ring before. Definitely never one with it just over 90 degrees off.

What’s the date of MFG I can’t make out the serial and perhaps DIBS!

Tubber · Jan 4, 2018

Looks like September 1970.

tritto · Jan 4, 2018

Foo2rama
Never seen one with a pulsation ring before. Definitely never one with it just over 90 degrees off.

What’s the date of MFG I can’t make out the serial and perhaps DIBS!

The inner ring rotates by turning the crown - why is a matter of conjecture.
There is also a school of thought that these aren't meant to literally time blood pulses, but to calculate the number of items being produced off a production line over a period of time. Hence the alternative 'donut production timer' moniker

Foo2rama · Jan 4, 2018

tritto
The inner ring rotates by turning the crown - why is a matter of conjecture.
There is also a school of thought that these aren't meant to literally time blood pulses, but to calculate the number of items being produced off a production line over a period of time. Hence the alternative 'donut production timer' moniker

Interesting I thought the inner ring was fixed on these.

Normally tachymeters are used for production lines... but I can see a pulse bezel doing it too.

erpin9 · Jan 4, 2018

Outstanding information about the other use of the pulsation ring. Thanks Tritto.