This post is just a short update to a watch that was on the bench earlier this year, namely an Astron 35-9000 date.
You can read about this watch and its brother the no date Astron here, a quick synopsis is that both watches were serviced but only one of the circuits/oscillators was in a working condition so the owner elected to have the no date example as the running watch whilst he searched for a replacement oscillator and circuit for the no date version. Good luck with that!
Well a little while ago to my astonishment the watch arrived back in the post along with these little beauties, a calibre 35 circuit and quartz oscillator. How this chap manages to find replacement parts for a watch whose total production (date and no date) 47 years ago was round about the 1500 mark is a mystery to me, but thank goodness he can 🙂
As the watch had been serviced earlier in the year it was simply a case of removing the movement and swapping out these two components, here’s the movement with the old circuit block and oscillator still in place.
The faulty components are removed in this photograph.
And the new ones are fitted in this one.
It’s always a nerve wracking time working with vintage watch integrated circuits as you never really know if these replacements are going to work properly or not until they’re fitted. However, once the movement was energised it sprang into life with a current draw of between 6.94 and 7.11µA when running and 2,87µA when hacked which although hungry by today’s standards is what I’d expect from a freshly serviced calibre 35. The only issue was the sweep hand was a bit jittery but a tweak of the (jewelled) centre wheel detent soon had it operating correctly. I’m not envious of a chap who has a pair of functioning 18k gold date and no date vintage Seiko Astrons in his collection, honestly I’m not! 😉