Ronda 775 slow date change?

[PeterS]

I have a Ronda 775 quartz movement here and the date wheel starts moving at about 23:30 and snaps into position  just after 12:00, quick date set works as expected.
Is this 30 minute date change normal or is there something that needs repairing?

[watchweasol]

I Would say normal, My Lorus quartz does exactly the same.

[PeterS]

40 minutes ago, watchweasol said:

I Would say normal, My Lorus quartz does exactly the same.

Is it Ronda 775?

[Lwayslate]

I agree, that's normal. I've come to the conclusion that a lot of watch companies have the date change start before midnight because you already know the date. Quick Google search showed that the movement probably does not cost more than $20 so I wouldn't expect it to having instantaneous change.

Sent from my BBF100-2 using Tapatalk

[watchweasol]

No Its Seiko Epson unit   but  they all change there or there    about  I have seen some that start a 11.45 and complete about 12 15.  It takes a little while for the wheel to over come the the detent on the up hill path and then snaps in on the down path.

[Lwayslate]

Also usually the manual date corrector uses a different mechanism than the time keeping date change drive, hence the difference in action.

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[PeterS]

I should have checked it before I started. Although I am almost certain that the slow change is right. I would imagine that the change is either instantaneous or slow. It would have to be a magic fault to change the date slowly and snap at midnight.

I know nothing about quartz movements but I am kind of shocked. I used to have a quartz Seiko perpetual calendar 20 years ago and that used to change instantaneously at midnight. This movement is in an expensive Tag Heuer watch and I wasn't expecting the date to change slowly.

[PeterS]

2 minutes ago, Lwayslate said:

Also usually the manual date corrector uses a different mechanism than the time keeping date change drive, hence the difference in action.

Sent from my BBF100-2 using Tapatalk
 

Very much the same as mechanical Seiko movements. I wasn't expecting the same from a quartz movemet.

[jdm]

1 hour ago, PeterS said:

II used to have a quartz Seiko perpetual calendar 20 years ago and that used to change instantaneously at midnight.

That is 4F/8F modules have a motor dedicated to the (perpetual) date function, and no manual quick setting.

1 hour ago, PeterS said:

This movement is in an expensive Tag Heuer watch and I wasn't expecting the date to change slowly.

Expensive for the buyer but cheap for TH to manufacture. Torque, especially in quartz module, is a limited and very valuable resource, you need more torque to ramp up against the slope of an instantaneous change mechanism. Unfortunately in mechanical mov't more torque means fitting a  stronger mainspring, that is thicker, so you have to sacrifice power reserve with a same size barrel size. Result, we have the much revered ETA 2824-2 beating 28.800, instantaneous date change, and 38 hours power reserve. Compare to the humble Seiko 7S26/4R which deliver 42 hours, with the compromise of slower beating rate (which actually will make it last longer), and a date and day which is so slow, to cause  a great nightly discomfort to the OCD buyer.
On quartz modules torque is not there at all, so either add some comlication to accumulate torque, or fit an additional motor.

[PeterS]

Now I know what to expect from quartz watches. If I didn't used to own the Seiko with a snappy change at midnight I probably wouldn't even think about it as I'm used to mechanical Seikos. I never knew/thought about the torque required for the date change, thanks for the explanation.
I've returned the watch and the owner is happy with it.