Last night the watch stopped, and I was a bit suspicious: surely it wasn't that long ago that I had the battery replaced? I found the receipt and sure enough it was replaced two weeks less than a year ago. They usually last 18 months.
I checked on the web to see how difficult it was to actually DIY the battery replacement and it wasn't actually all that difficult. I prised off the back with a penknife blade without a problem, levered out the battery and saw a ring of corrosion around the battery's centre contact.
Well that's why it stopped then, the jeweller's had obviously stuck an out-of-date battery in there, charging me a tenner for the privilege. So I won't be going there again!
Well as it turned out they closed down in September this year so I won't be going there anyway. But now I've got the back off I found the battery number and ordered a couple of new ones on Amazon and in future I'll DIY the job.
So this is a sort of cheer as well.
