Miyota caliber OS2O

Miyota Caliber 0S20

Miyota caliber OS2O 0s20
Example of a Miyota 0S20 in a Philip Stein Extreme Chronograph Watch
ManufacturerMiyota (Citizen)
Caliber Number0S20 (sometimes typed as OS20)
TypeQuartz
Replaces CaliberUnknown, please add in the comments below
Diameter13.50”’ (30.80mm)
Height5.1mm
Battery Cell NumberSR927W (395/399)
Battery LifeApproximately 5 years
Frequency32,768Hz
Quartz TypeTuning fork type quartz crystal
Stem065-441 (tap 10)
Hand Sizes1.20/.70/.17 (small hands also .26)
Jewels0
FunctionsHours, minutes, central chronograph seconds, 60 minute counter, 24 hour hand, date
Country of ManufactureJapan
Known Models
Bulova chronograph, Philip Stein Extreme Chronograph, TW Steel A1GP Chrono, Invicta Speedway Chronograph Original Version (Too many to list, add yours to the comments below…)

The Miyota caliber 0S20 is a quartz chronograph watch movement. You might also see other listings incorrectly refer to this movement at OS2O, but is should be zero-S-2-zero not O.

Accuracy:

Miyota claims the accuracy of this movement to be +/-20 seconds/month.

Recalibrating the chronograph hand to zero:

It is common for a quartz chronograph hand to be misaligned after a battery change. If your central chronograph second hand (or chronograph minute hand) is not resetting to 12:00 or “zero” position, you can try the following steps:

  1. Pull the crown to position 2
  2. Press button A (top button) to advance the chronograph hand forward until it is lined up with 12:00. If you long-press A, the hand will move forward faster.
  3. Push button B (bottom button) to reset the 60 minute chronograph hand (subdial located at 9:00).
  4. Push the crown back to position 0

Note: if you push the crown back in to position 0 while the chronograph hand is still advancing forward, then it will stop the chronograph hand and recognize it as zero position. In this case, you will have to start over again.

Miyota 0s20 Chronograph Reset

Replacement prices:

The average replacement price at the time of this post was from $26.95 – $36.95. Try here.

Macro Gallery:

 Video of 0S20 Assembly and Disassembly:

Examples of watches with Miyota caliber 0S20

Additional Resources:

Search Assistant: OS2O, OS20, 0S2O, O52O, 0520

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Arthur
Arthur
8 years ago

What movement is used in the majority of Bulova Marine Star watches?
Unable to find answer anywhere on the internet.

Arthur
Arthur
8 years ago

Is it the Miyota OS20 or the Miyota OS10 that is used in Invictas Corduba
With 2 marvelled registers chronograph? One register atop the other in
Center of dial?

Arthur
Arthur
8 years ago

Auto correct. Marveled registered should have read Barreled Registers in
Center of the dial.

Michael
Michael
7 years ago

Is there an AC pad? Wondering if it is the (-) marking.

Aaron
Aaron
7 years ago

Is there any way to modify the OS20 movement do that it keeps time half as fast as normal?

So that it would work with a 24hr watch.

Jim
Jim
7 years ago
Reply to  Aaron

That is an interesting question Aaron. Can you explain more?

Martin
Martin
6 years ago
Reply to  Jim

Hello Aaron,

yes, this can be accomplished by a hardware modification:
simply replace the 32768 Hz crystal with a 16384 Hz crystal
and the watch will run at half the original speed.

The downside of this modification is that the chrono speed will of course also be halved.

Regards
Martin

Herbert Gomes
Herbert Gomes
7 years ago

I would like to get the pointers to the 0S20 model. How do I do?

Jose Enrique Prades
Jose Enrique Prades
7 years ago

tengo un rolex que por dentro es igual que este de la imagen ,me estan diciendo que no es rolex autentico ,no me lo creo,si fuera imitacion no llevaria esta mecanica

Edwin
Edwin
5 years ago

Tu Rolex es falso amigo. Los relojes Rolex son suizos, fabrica sus propios calibres y ademas casi todos son automaticos a escepcion del Rolex Oyster Quartz

Wilson
Wilson
7 years ago

Para que sirven las indicaciones A1 A2 A3 A4 y los demas simbolos escritos en la parte de atras de los miyota os 20 demas calibres.

Wilson
Wilson
7 years ago

Para que sirven las indicaciones A1 A2 A3 A4 y los simbolos en la parte de atras de las maquinas miyota os20 y en otros calibres.

Tony
Tony
6 years ago

Where can I get a new face dial for the Miyota OS20 plus new Sub Dial Hands, what is the size of the Sub Dial hands
Many thanks & kind regards
Tony
Tony Arnold
arny@helios-electronics.com

Tony
Tony
6 years ago

Many thanks have ordered hands on Ebay
Kind Regards
Tony
Tony Arnold

Tyo
Tyo
6 years ago

Hi.
I have jorg gray 6500-11 with miyota os20 machine, i have problem to reset chronograph minutes hand on 60 position, when set crown at 2nd position then i pushing B button, the chronograph minutes hand back to 15 position, in anotherhand chronograph second hand back to 12 or zero position ..how to reset chronograph minutes hand?

Thank you

Martin
Martin
6 years ago
Reply to  calibercorner

Hello Tyo,
I have answered your question in the comments to the Miyota Caliber 0S10 on this site
Regards
Martin

Luis Santos
Luis Santos
6 years ago
Reply to  calibercorner

The instructions are about the seconds chronograph hand only. There is no such way to easily reset the minutes chronograph hand.

Ray
Ray
6 years ago
Luis Santos
Luis Santos
6 years ago

The german watch Dugena, model “Monza WR100”, also uses Miyota 0S20 caliber. It’s also marked on the steel back cover.

David Z
David Z
5 years ago

This movement was used in the older Invicta Speedway 9211. the current movement is the Hattori VD53B-14, with the chronograph seconds at 6:00

Stephen Borchert
Stephen Borchert
5 years ago

Reactor Photon 79015 Chronograph.

MdeBruns
MdeBruns
5 years ago

Is it possible this mechanism Miyota OS20 inside a Tag Heur original?

Luis Santos
Luis Santos
5 years ago
Reply to  MdeBruns

Everything is possible. And this is a really reliable and good quartz movement.

MdeBruns
MdeBruns
5 years ago
Reply to  Luis Santos

Luis, thank you for your reply. What i’m trying to know is : A Tag Heuer whatch, original, have this mechanism, or is a replica ?

Luis Santos
Luis Santos
5 years ago
Reply to  MdeBruns

I’m not sure, but if could bet would be a NO. I don’t think, despite its quality, that a original Tag Heuer would use o Miyota caliber.

MdeBruns
MdeBruns
5 years ago
Reply to  Luis Santos

Tks, Luis !!

Derza
Derza
17 days ago
Reply to  MdeBruns

i have a tag heuer watch (monza calibre 36) from my uncle. and the movement was a Miyota 0S20. Actually, same as you, i am wondering is it an original tag heuer or not.

Luis Santos
Luis Santos
5 years ago

How can I adjust the minutes (not the seconds) chronograph hand?

Alin
Alin
5 years ago
Reply to  Luis Santos

hey Luis, did you find a solution how to calibrate minutes hand from the chrono function?

WISeman
WISeman
4 years ago
Reply to  Alin

You cannot do that.

Damian M
Damian M
5 years ago

my OS20 resets the chrono seconds hand back in time every single time… when i calibrate the hand to top 12… run the chrono a few seconds and reset it it will be somewhere between 9-10… if i do it again it will be somewhere between 6-7… again it will be between 4-5… and over and over and over…. will never reset itself back to the 12 oclock position i calibrated it tooo/… any thoughts??? literally a brand new watch… received it mail today. im trying to contact the seller to see when can be done.

Luis Santos
Luis Santos
5 years ago
Reply to  Damian M

This malfunction can occur due to low battery. Try to replace it.

Fernando
Fernando
4 years ago

This movement is used in the Nautica Chronograph 100m

jeicol
jeicol
4 years ago

how can I return the minute pointer of the chrono back to zero position?? philipp plein Spitfire watch uses Miyota 0520 too

Loh SK
Loh SK
4 years ago
Reply to  calibercorner

My expereience with OS20 is a loose fit of the minute to the pin on the movement. Because the minute hand have to fly back to zero position, a loose fit will result in the minute hand returning to different positions . Look for a tighter fit minute hand

trackback
Jack Mason Watch Review: Do They Know Jack?
4 years ago

[…] Miyota 0S20 quartz runs at the heart of the Halyard Sport. Miyota is known for making high-value […]

Belén
Belén
4 years ago

Hola de q parte son? Quiero comprar está makina soy de argentina

Alberto Carballo
Alberto Carballo
4 years ago

Does anyone know how to dismount the stem? Where do I have to push for the stem go out? Thanks

Tarek
Tarek
3 years ago

I just did it. It’s right where it says “<- push" at the bottom. Don't press too hard just gently

Sam
Sam
4 years ago

I have this movement in my Nastro Azzurro, se pictures.

Yash
Yash
4 years ago

I have this watch but i don’t know this watch company name
So please tell me
It also has miyota os20

Yash
Yash
4 years ago
Reply to  Yash
  • 
trackback
Mercedes versus BMW Watches - The Truth About Watches
3 years ago

[…] least they deign to inform us that the Chrono’s powered by a Miyota OS20 Japanese quartz movement. Miyota claims +/-20 seconds/month accuracy – hardly the kind of […]

Eugen
Eugen
3 years ago

Hi guys. I have a replica tag Heuer with miyota 0520 movement. That’s what it says on it. But the date is between 7 and 8 not between 4 and 5 o’clock. I can not see it anywhere. Any idea where to find a movement? Or a crown with the stem ?

Realwatchesonly
Realwatchesonly
3 years ago
Reply to  Eugen

It probably just means the date window on the dial was cutout in a different place.

Eugen
Eugen
3 years ago

I just realised that the cutout doesn’t matter. Thank you very much.

Derza
Derza
17 days ago
Reply to  Eugen

so it means every tag heuer with miyota 0S20 must be a replica? i had one Tag Heuer Monza Calibre 36 with this movement. Its from my uncle so i wouldnt know it is replica or not.

enrique
enrique
3 years ago

Hi All,

please help provide electrical requirement like Normal current consumption and oscillation starting voltage

Fassot
Fassot
3 years ago

Bonjour j ai une hublot Big Bang miyota co et la petite barre du nombre 1 est décollé comment démonter le cadran pour la recoller?merci c est un modèle 0520

Fassot
Fassot
3 years ago

Combien vaut une Big Bang hublot 0520 fait par miyota?

Civlov71
Civlov71
3 years ago

Hi I am trying to find out what other hands fit the vk63 movement? i want to put a sweeping movement on my watch.

thanks

Monxur Russell
Monxur Russell
2 years ago
Reply to  Civlov71

Me also trying to replace a VK63 movement instead of 0S20. Does those hands fit over VK63 and the same distance between the hands? TIA.

trackback
Miyota Watch Movements (List) Watch Movement | Caliber Corner
2 years ago

[…] 0S20 […]

Robert
Robert
2 years ago

These movements are often used in LUM-TEC quartz models such as RPM models or B Combats…

Ian Watson
Ian Watson
2 years ago

I have this in my recent acquisition Chrono Diamond Boreas which apparently sports eight “real” diamonds on the dial O.o I have a problem where the central second hand is just half a second off the 12 mark and its super irritating, the pos 2 adjustment puts it either before or after the 12 and neither looks “right”

Steve Ignat
Steve Ignat
1 year ago

How is it that the chronograph works on my 0S20, but the time keeping hands will not move?

Steve Ignat
Steve Ignat
1 year ago
Reply to  Steve Ignat

ANYONE???

MatterThanEver
MatterThanEver
9 months ago
Reply to  Steve Ignat

All of this will sound insane, but the likelihood of having a 0S20 fail only in this one area is remote enough that anything is possible. A) If youve opened it all the way up and removed the face and the smail hands were all connected, you have a rare failed 0S20. B) If you haven’t, i suspect the watch was made with a dialface that doesn’t accommodate the 3 little posts and the hands are not real. C) Your local ISP is using that section of your 0S20 to increase their black ops wireless bandwidth. I know; you would… Read more »

Herbert
Herbert
1 year ago
Where can I find the 6 hands of the Miyota 0s20?
Tom
Tom
1 year ago

I have a Continental chrono that is an IWC look-a-like with this movement. Glad you have the battery type listed.

Alan LaRue
Alan LaRue
1 year ago

I have searched everywhere and cannot find any information regarding the setting of the 24-hour dial. It isn’t in the Bulova manual, or any Myota documentation that I’ve found, and oddly, no one seems to have asked the question online! I tried the Seiko method — pull the crown out to the first stop — but that didn’t do anything.

Can you help?

Thanks,
Alan

keepthetime
Admin
1 year ago
Reply to  Alan LaRue

Hi Alan, the 24 hour hand on this movement cannot be set independently. It mirrors the main time. It is not a GMT or dual-time, it is more for military time or used as a day/night indicator.

Alan LaRue
Alan LaRue
1 year ago

Thanks for the information. Unfortunately, it’s 12 hours and 5 minutes behind. I suppose it would have to be taken apart to fix it then.

keepthetime
Admin
1 year ago
Reply to  Alan LaRue

Is the date flipping at 12:05 rather than 24:00?

Erik Waaler
Erik Waaler
1 year ago

Hi. Is the Miyota movment 0S20 the same as Bulova uses called JS20?

10tocantes
10tocantes
1 year ago

The section about recalibration of the chronograph hands is incorrect. When crown is fully opened in position 2, only the chronograph seconds hand can be recalibrated by pressing on the A push button at 2.

Minutes hand of the chronograph is mechanically operated and cannot be calibrated. If found not to be at zero position when chronograph is reset, the hand can only be manually refitted to its correct position.

Same applies to other 0Sxx Miyota quartz chronograph movements such as 0S10, 0S30, etc.

These are the closest you can get from a real mecaquartz movement.

Brand:
Seagull Caliber St19

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