Ronda Caliber 8040.N

Brand	Ronda
Caliber Number	8040.N, 8040, 8040N
Line	Mastertech 8000
Type	Quartz
Linges	15”’
Diameter	34.6mm
Height	5.6mm thick
Battery Cell Number	395
Hands	1.20mm/0.70mm/0.20mm/1.60mm
Claimed Battery Life	48 months
Jewels	13
Hacking?	Yes
Functions	Hours, minutes, central chronograph seconds, 1/10 seconds counter, 30 minute counter at 9:00, 10 hour counter at 3:00, retrograde day at 12:00, big date at 6:00, small seconds subdial at 6:00
Country	Swiss Made or Swiss Parts
Known Models	Invicta 13686, Invicta Sea Hunter 1064, Invicta Subaqua Noma II (add yours to the comments below…)

The Ronda caliber 8040.N is a multi-function quartz movement with 13 jewels. It is part of Ronda’s Mastertech line.

Pros and Cons of This Movement:

Pros

• Decent battery life (as long as you don’t run the chronograph constantly).
• Cool retrograde day of the week at 12:00
• Big double digit date at 6:00
• Takes a common battery

Cons

• No quickset for the day of the week!
• Small screws are easy to lose during battery replacement.
• High cost for movement replacement.

Functions:

According to the Ronda website, the caliber 8040.N features:

• Repairable metal watch movement
• Very long battery life
• Power saving mechanism with pulled out stem: Reduction of consumption approximately 70%
• Very easy handling by two pushers
• Big date with quick change

As Ronda mentioned, the big date has a quickset function but the day of the week does not. When setting the day of the week, you will have to put the watch in time setting mode and go all the way around until the day of the week indicator points to the correct day.

Movement Drawings:

How to Change the Battery:

Changing the battery on the Ronda 8040.N isn’t difficult, but you have to be very careful not to lose the 2 tiny screws that hold the battery clamp (battery cover) down. Also, make sure the orange insulator film located below the battery doesn’t fall out. You will need battery cell #395 which you can order here.

• Once you have the caseback removed, unscrew the two screws and lift up the cover.
• Put a new battery in with the positive side up (markings on the battery up).
• Carefully replace the cover, sliding the lip below the movement plate.
• Replace the 2 screws.

Replacement Prices:

At the time of this post, replacement prices for the 8040.N were found in the range of $95.95 to $112.95 USD.

Watches with caliber 8040.N:

This caliber was submitted by Bill. He found it in an Invicta Reserve model number 13686:

“One of Ronda’s more elaborate and expensive Swiss Made Quartz movements. RONDA Mastertech Caliber 8040.N Size 15”’ Found in several Invicta models, and probably other brands also.” -Bill B.

The photo at the top of this post is of an 8040.N found in an Invicta Jason Taylor Chronograph watch.

This caliber was also found in this Invicta Subaqua Noma II.

More watches with this movement:

Additional Resources:

• Official tech sheet from Ronda here