ISA Caliber 9238/1970

Manufacturer	ISA
Caliber Number	9238/1970, 9238/1971
Updated Caliber Number	9238A2
Movement Type	Quartz, battery-powered
Lignes	10.5”’
Overall Diameter	23.9mm
Casing Diameter	23.3mm
Height	4.13mm
Jewels	0
Frequency	32,768 Hz
Accuracy Rating	+/-15 seconds/month
Battery Cell Number	371 / SR920SW (silver oxide, 1.55 V)
Battery Life	32 or 67 months (see below)
Driving System	One piece step motor (1 step/sec)
Stem	401-1610 (9mm diameter)
Stem Height	2.18mm
Stem Travel	.5mm
Hand Sizes	1.50mm / .90mm / .20mm / 3 x .16mm
Functions	Central hours; central minutes; central seconds; pointer date subdial at 3:00; pointer style day of the week subdial at 9:00; dual time / 24 hour subdial at 6:00
Subdial Layout	3-6-9
Hacking Seconds?	Yes (mechanical and electrical stop device)
Country of Manufacture	Far East Ass’y/China or Switzerland/Swiss Made
Known Models	Various Invicta models (Add your watch in the comments below…)

The ISA caliber 9238/1970 (aka 9238/1971, 9238A2) is a quartz movement with a day/date and a 24 hour/dual time indicator. The calendar and dual time complications are displayed via subdials that resemble a chronograph watch. There are also pushers on the side of the case, completing the chrono look, however, this movement has no chronograph functionality.

As with all ISA calibers, this movement is discontinued. Official tech sheets were found dated as recently as 3/2014.

Swiss Made VS Far East:

There are many different ISA cal. 9238 versions with some being Swiss Made, some Far East Ass’y (assembly), and some available in either country of origin. This particular configuration is available as Swiss Made or Far East.

The country of origin determines the caliber number and battery life. See the chart below:

Country of Origin	Caliber Number	Battery Life
Far East (China)	9238/1970	32 months
Swiss Made	9238/1971	67 months (maybe 49)

ISA appears to have quoted various battery autonomy over the years. For the Swiss version, some documentation quotes 67 months, others quote 49 months. How Caliber Corner interprets this is: the original Swiss 9238/1971 may get 49 months of runtime on a fresh battery, and perhaps the updated 9238A2 gets 67 months – note that this is unconfirmed.

Where is Far East?

“Far East” was ISA’s way of saying China without having to say China. This was before China-based sites like Aliexpress became all the rage for the factory-direct made in China niche of the watch community.

In the example pictured at the top of this page, it appears that Invicta had the movements in their watches laser engraved to add two additional lines of text: “CHINA / INVICTA WATCH GROUP”.

It is likely that Invicta added the “China” text due to import customs requirements in certain countries, since “Far East ” is not a country. Some countries require the actual country of origin to be marked on the movement to meet import requirements.

How to tell the difference?

The movements themselves only carry the first part of the caliber number “9238”.

The main way to determine the exact caliber in your watch, is to look for “Swiss” or “Far East” text.

How to set the time/date:

• Pull the crown out one click to time-setting mode to set the hours and minutes.
• To set the day of the week, advance the main hands continuously until you get to the correct day.
• To set the date, use the top pusher to advance the pointer date hand.
• To set the dual time indicator, press the bottom pusher to advance the 24 hour hand.

Replacement Prices:

At the time of this post, replacement movements were found online in the range of $18.95 USD to $24.50 USD.

Additional Resources:

• Caliber 9238 Instruction manual from ISA
• Caliber 9238 Datasheet from ISA