WS 6: Repairing a Caliber PUW 910: Removing the Circuit
In this picture you see the shiny new battery contact just in
front of the insulating prong that stabilizes it. Needless to say, the new
battery contact did not do the job, there was another error hidden somewhere.
After I had removed the circuit and found those corroded coil contacts, I was
100% that is it now! An inspection of the old coil under the stereoscope also
revealed that indeed one of the contacts was loose! You will see better shots of
the partially dismantled PUW910, I needed to focus the light on the coil contact
to show its corrosion.
I still did not quite trust my luck finding the battery contact, thus I first tried to solder that coil contact. A very nifty work, especially since you have to work with a 10x loupe. Soldering under the stereoscope proved to be too challenging for the fingers... but the wire was too thin and I also noticed that the part after the original soldering point - most likely the factory had used spark soldering - was broken off, so the wire was too short. I had even tried to pull slightly with tweezers Nr. 5, the coil was wound too tightly, the wire would not budge.
I put the project on hold and made a note that I needed a spare coil. A couple of weeks later, I was in a completely different part of Bangkok: Yaowarat Road, Chinatown. I spotted a watch parts shop that I had not seen before and entered. "A spare coil for a PUW910 please" I heard myself saying not believing that there was any possible answer then "Sorry, never heard of this, what is that PUW910". Well, I had to pinch my underarm a second time. "One, two?" was the answer and within seconds the shop owner was back, smiled at me and said "100 Baht" (ca. USD 2.50). I started believing now that the PUW910 must have been really popular, everybody except me, seemed to know it.
You find a Watchhunting Article about that day and a picture of that shop here. Please use your browser's back button to come back here.
Please click on the picture to read on >>>