Seiko
Birthday Watch October 1974! Seiko 5 Sports 6139-8050 Speed-Timer "Deep Blue" JDM Chronograph SUWA 23J Automatic Watch (OH) watch only
Basic Info
Listing code : QMG2P2
Brand : Seiko
Movement : Automatic
Case material : Steel
Bracelet material : Steel
Year of production : 1974
Condition : Used (Very good)
Most Recent Servicing : September 12, 2023
Scope of delivery : No original box, no original papers
Gender : Men's watch/Unisex
Location : Singapore
Price : S$1,388
Availability : Item is in stock
Caliber
Movement : Automatic
Caliber/movement : 6139
Power reserve : 42 h
Number of jewels : 23
Frequency : 21600 A/h
Case
Case material : Steel
Case diameter : 40 x 41.5 mm
Thickness : 14 mm
Water resistance : Not water resistant
Bezel material : Steel
Crystal : Plexiglass
Dial : Green
Dial numerals : Lines
Bracelet/strap
Bracelet material : Steel
Bracelet color : Silver
Lug width : 19 mm
Clasp : Buckle
Clasp material : Steel
Buckle width : 18 mm
Functions
Chronograph, Date, Weekday
Other
Central seconds, Small seconds, Quick Set, Only Original Parts, Vintage, Special Edition
A BIRTHDAY WATCH IS A WATCH THAT WAS PRODUCED THE SAME MONTH AND YEAR AS YOUR BIRTH MONTH AND YEAR
Make: Seiko
Type: Automatic
Model: Sports 5 Speed-Timer Series
Year of Production: October 1974
Movement: 6139
BPH: 21,600
Number of Jewels: 21
Hand and Dial: 3D Baton Silver Indices and Syringe Hands
Width: 40mm
Lug to Lug Height: 41.5mm
Thickness: 14mm
Lug Width: 19mm
Bracelet: Original Seiko 5 Sports Super Engineer Signed SS bracelet
Pouch / Box: Brand-New EVA Type Zipper Pouch
A brief history:
"Today, self-winding (or automatic) chronographs are quite common. Omega created a prototype of one back in 1948 but later abandoned their production plans. Over 20 years later, two companies and one collaboration would finally make it to series production: Seiko, Zenith, and a joint venture between Heuer, Breitling, and Hamilton. These manufacturers all introduced and launched their automatic chronograph movements in 1969, and this watch style would quickly become very popular throughout the industry.
"Of the 3 calibres, the Seiko 6139 has had the greatest influence on future generations despite being the least well known. This movement centers on its vertical clutch and compact automatic rotor, a design many manufacturers have imitated since the 1980s. In fact, Frederic Piguet turned to the 6139 when crafting their legendary caliber 1185, which some call the “grandfather of the modern automatic chronograph.” Considering how many automatic chronographs the 1185 has inspired, there’s no denying the 6139’s influential role.
"In 1969, Suwa Seikosha put the final touches on the caliber 6139, complete with a Magic Lever and vertical clutch system. On May 21, 1969, Seiko officially debuted the movement under the name “61 Speed-Timer.” However, the caliber had already begun appearing in watches as early as January of the same year; you can still find examples from those early months today. Seiko published the first advertisement for their new automatic chronograph in February 1969. Both the company and Ohki were unaware that the 61 Speed-Timer was the world’s first automatic chronograph movement. At the time, Seiko was busy planning the release of the quartz Astron later that same year." - The Chrono24 Magazine.
So, the Seiko 6139 may be considered the great-grandfather of the modern automatic chronograph timepiece!
The Seiko 6138 and 6139 movements were specifically designed for their newly developed watch range ~ the Chronograph that took the world by storm.
The 6139 is the world’s first automatic chronograph that uses a column wheel and vertical clutch. The 6138 followed shortly afterwards. Both were nicknamed “61 Sports Speed Timers” even though certain models did not indicate these wordings.
The 6138 was developed on the 6139 platform but with the intention of having an added chronograph hand to measure elapsed hours; and it also included the column wheel and vertical clutch for more precise stopwatch measurement. But, unlike the 6139 that only has one sub minutes dial, the 6138 comes with two – a 30-minute counter and a 12-hour counter.
Here we have the 6139B-8050 also known as "Deep Blue" because of its Emerald Blue dial that is reminiscent to the ocean. Like most 6139s, the Deep Blue is only equipped with one 30 minutes mini dial that is white with a second black hand.
For Seiko Collectors and Vintage fans, this is a Seiko 5 61-SPEEDTIMER SUWA-6139B-8050 JDM "Deep Blue" in immaculate condition.
A deep cleaning was conducted on this seldom seen October 1974 Seiko Deep Blue dial, white day/date window, chapter ring, 3D-styled silvery-white baton markers, syringe hands and mini-dial hand as well. They are now extremely pleasing to the eye.
Its case with built-in lugs and original Seiko Super Engineer bracelet were cleaned via ultrasonic immersion and a good polished soon followed to reveal a fantastic finish albeit a few minor scratches that are barely noticeable. The crystal is original and is in good condition after a good rub.
The crown is located at the traditional 2H, 3H and 4H positions and are nicely tucked away to prevent damage or snags. The day / date and hands quickset works as it should by uncorking the 3H crown to the first and second levels to adjust accordingly. Crown 2H is for the chronograph start/stop and the 4H is for the reset of mini-dial and main second hands. All are working as they should.
Because it is a JDM, the Day is in English and Kanji.
The movement was stripped, meticulously cleaned via ultrasonic immersion, oiled, re-assembled, and calibrated on 12 September 2023. In short, it was given an overhaul and not a standard servicing. It should be able to operate unhindered until the next servicing thereby giving the owner peace of mind.
Equipped with the highly prized 6139B movement, it has 21 Jewels and operate at 21,600 beats BPH. The time-grapher shows readings of +1 second and amplitude of 163 with a straight and somewhat centered line.
