My broadband has been sorted (needed a new cable from the roadside cabinet to the house) but I have missed replies to a few enquiries, especially via the ‘ask a question’ box in the side bar. I do apologise for this. I managed to mark all my emails as ‘read’ so I’m not sure which replies are outstanding.
If you have not heard back from me, please get back in touch and I will try to help with any queries you have.
Apologies for not replying to recent comments, it’s partly due to internet connection problems which have been a PITA especially over the last week or so. An engineer is coming tomorrow, so hopefully I’ll be back in business after that.
I’ve recently had an email exchange with a blog visitor about a case back marked 62-7275 and 4-540310 – unfortunately all the emails have gone missing, despite searching every folder! No idea how this has happened, but please get back to me 🙂
I’ve covered Citizen’s range of automatic chronographs in some detail, but made less reference to their hand wound models based on the 5700 calibre. I’m now very pleased to bring your attention to a new reference page, put together by an avid 5700 collector, which provides excellent detail about all the hand wound chronographs Citizen produced in the late 1960s / very early 1970s. It is very well put together, with great textual and pictorial information, and can be found here:
The Ultimate Citizen Recordmaster Collectors Guide
It’s the weekend so today’s watch is a hand winder 🙂 The Diamond Flake was Japan’s thinnest watch when it was launched in 1962. The 25 or 31 jewels 0700 movement was a mere 2.75mm deep, beating the Seiko Gold Feather by just 0.2mm. My example is from September 1963 – I haven’t had chance to do a fresh photo today, so this is an old one:
A change today from a watch feature to something that’s always been a bit of a mystery – the letter stamped at the end of Citizen’s case numbers. Although not needed as a part number since the case number alone, e.g. 4-123456 provides that, I have never pinned down just what the additional letter indicates. I wrote to Citizen Japan about it – didn’t get a reply! So I’m left to my own theory 🙂
Most vintage Citizens with the above case number format, typically from the late 1960s and on through the 1970s have ‘TA’, ‘K’ or ‘Y’ stamped alongside the case number:
My theory is that these letters are factory codes – relatively recently I got hold of a scanned catalogue from the early 1970s, and that includes a list of factories:
My best guess is that ‘TA’ is the Tanashi or Tama Seimitsu factory, ‘K’ is the Kawaguchiko factory (dials were made there and dial codes often include ‘KA’ too), and ‘Y’ is …… not so obvious! You can see as well the ‘Star’ Seimitsu Company – older watches have ‘STAR’ marked on them since they initially made cases for Citizen, but later produced smaller parts, particularly screws.
Today’s piece is another battery powered model, and although it’s a Cosmotron, it’s something of an anomaly. Unlike any other Cosmotron this one does not have a magnet driven hairspring – in fact it is a ‘hummer’ – a tuning fork watch. I don’t know why Citizen branded this as a Cosmotron – my only theory is that the design of the single coil 3701B movement was their own, and not made under licence from Bulova as was seen with their Hisonic range. There’s no mistaking it’s a hummer either – it hums very loudly, and is not the best thing to have on your bedside table if you want a good night’s sleep! I’m not a great lover of roman numerals on watch dials, but they work well on this one in my opinion. The finely printed black hour markers contrast well with the clear white dial (not very well shown in today’s photo), whilst the slender hands also have a fine black centre line – it’s a very smart look. The GX is a fairly rare watch, so a nice one to add to any collection. This one is from November 1975: