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Ronda (915) Battery Change


MikeB

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Have 3 watches with Ronda 915, 5 jewel. Fresh 371 Energizer batteries. Two have orange isolators, one does not.  Can't get any of the three to work!!! Installing plus up with the crown out.

What is the easiest way to check the movement? Use Renata batteries instead?

Have changed many batteries over the years but this has me stumped. 

HELP

 

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There isn’t much information to go on here. Can you check all the batteries with a voltmeter or try them in a working movement? Also, I know it’s obvious, but you are pushing the crown back in afterward,right? Sorry, have to ask, anything is possible. Can you take a picture or two? I don’t find a 915 movement number on their movement manuals site. Steve


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A picture of the movement would be nice so we can see how the contacts are arranged. Googling is revealing that the Ronda 915 Doesn't appear to exist?  Then there is always a minor possibility the shape of the battery may be preventing the watches working.

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MikeB

As the others have said a picture would be useful as I can only find Ronda 519 but that's not a 5 jewel movement.

Also, have these been left with a discharged battery for any length of time?





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12 hours ago, MikeB said:

Have 3 watches with Ronda 915, 5 jewel. Fresh 371 Energizer batteries. Two have orange isolators, one does not.  Can't get any of the three to work!!!

Have you bought these recently? Maybe they have been sold because they were broken. 

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I once had a movement that would not run after battery change, even trying several batteries of the same make.   I got it going by sticking a small piece of insulation on the -ve battery tag (connects to the bottom of the battery) where it goes from the edge of the battery to the movement.  I suspect the replacement battery shape was different from the original renata fitted and was shorting at this point.  Maybe worth a try.

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Ah right I recognize that Ronda well, and for all the wrong reasons.

There's two things people do to those movements practically all the time, one is to crush the battery contact to the side with the battery.

The second is scratch the coil while bending back that awkward battery retaining arm. The coils on these movements have no protective lacquer which means it wouldn't even have to be a scratched from a tool, it can be damaged just by touching with your bare fingers. 

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There's no AC function (where you connect two points with tweezers to reboot a watch) on this watch if that's what you mean by short start.
A few things i can see from the blurry pictures is that in 3rd picture your battery retaining arm is locked back and its also caught under the gear train bridge, best unscrew the top plate completely (as opposed to trying to bend it out) and refit in the proper position. There is a very clear mark of some kind on the first pictures coil.  Also on the third picture it seems to have been made with a longer contact point, which has possibly jammed into the date ring below. 

Lastly, i guess the movement frames were removed but you still have them to put back in?
 

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Ishima. Thanks for you help and quick response. I see the retaining arm problem in pic 1 and long contact in pic 3. Yes, I have all three movement frames. Have attached movement data sheet to assist with part no. communication.

How do I release jammed contact on pic 3?

Is there a way to test coil? (Without damaging?)

Does the orange insulator fit over or under contact?

Do I need to screw down the battery retaining arm or just make sure it is seated under screw?

Mike

Datasheet_715_Complete_technical_documentation.pdf

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