Ronda Caliber 706.4

Ronda caliber 706.4 is a Swiss Parts quartz chronograph watch movement. This caliber is part of Ronda’s normtech line of movements. The caliber number is located on the black plastic part near the battery.

Swiss Parts Vs Swiss Made:

There are two versions of this movement: a Swiss parts version with 1 jewel and nickel plated finish, and a 5 jewel version with gold plated finish. You may see Swiss parts variations listed as being made by Harley Ronda. The Swiss parts version is made in Thailand.

Accuracy Rating:

The expected accuracy is -10/+20 seconds per month in normal operating temperatures of 0-50 degrees Celsius.

Time Setting:

The crown on the 706.4 only pulls out one click.

• Position I – Crown against the case, watch running.
• Position II – Time setting position. Crown pulled out one click, watch stops.

Setting the Calendar:

To set the triple date calendar functions, use the pushers on the side of the case.

• Pusher at 10:30 – Sets the month subdial at 12:00
• Pusher at 8:00 – Sets the day of the week subdial at 9:00
• Pusher at 4:00 – Sets the date subdial at 3:00

There is no quickset for the moonphase. To adjust the moonphase indicator, you must advance the hands forward with the crown in time-setting mode until hands points to the full moon, or the position of the moon that you want displayed.

Hacking Seconds:

This movement has hacking functionality, meaning that the second hand stops when the crown is pulled out to time setting position. Ronda officially calls this:

Stop-second with interruption of motor impulses.

Ronda claims that hacking the movement activates a power saving mechanism that reduces battery consumption by approximately 70%. If you are not going to wear your watch for long periods of time with a battery installed, it is recommended that you pull the crown out to save the battery and reduce unnecessary wear and tear on the movement. Keep in mind that even if you keep the watch hacked, the battery can go bad and begin to leak which may damage the watch.

Changing the Battery:

When it’s time to change the battery on your 706.4 powered watch, you will need a 371 battery cell. If you can safely get the caseback off of your watch, then you should be able to change the battery with minimal difficulty. Just be careful not to touch the orange coil with your fingers or tools! You will see a screw near the battery, but do not unscrew it. Simply use your tool to gently slide the retaining arm over just enough until the battery pops up. When replacing the battery, be sure not to lose the orange insulator tab that goes underneath the battery. Put the new battery back in, making sure that it goes under the lip first, then carefully slide the retaining arm over again while pressing the battery down.

Stem Removal:

To remove the stem on the caliber 706.4, make sure the crown is in position 1 (pressed in) and use your tool to press the stem release button located next to the small arrow on the movement. It’s easy to remember this because the button moves to the side when the crown is in time setting position (to prevent the crown from being removed in the incorrect position).

Plastic Movement Holder:

The plastic movement holder that is included with this caliber also contains the pushers that create a contact between the case and the movement. This plastic holder is needed in order to use the pushers on the watch and set the calendar settings.

Replacement Prices:

Although this caliber appears to be discontinued and no longer supported by Ronda, replacement prices were found online for $26.20 USD.

Similar Calibers:

In addition to the caliber 706.4, Ronda also has caliber 706.1, 706.3, and 706.B. The 706.4 shown in this post is no longer available on the Ronda site and appears to be discontinued.

• 706.1 – Day of the week at 9:00, date at 3:00, moonphase at 6:00
• 706.3 – Month at 12:00, date at 3:00, moonphase at 6:00, day of the week at 9:00
• 706.B – Date at 3:00, moonphase at 6:00, day of the week at 9:00, month indicator via central hand pointing to the month on the perimeter of the dial.

The caliber 706.4 is most similar to the 706.3. The major difference is that the 706.3 has a moonphase indicator with a disc display and the 706.4 has a moonphase indicator with a hand display.

Pros:

• Long 60 months battery life.
• Inexpensive replacement price.
• Lots of complications packed in a small size.

Cons:

• Small size makes it hard to read the calendar subdials.
• The correct plastic movement holder is necessary because the integrated pushers are needed to adjust the calendar.
• Calendar sets when the crown is in position 0 (against the case) so it’s easy to accidentally advance the day or date.
• No quickset for the moonphase indicator.

Additional Resources:

• More Ronda movements here