I love it when I find a watch model that doesn’t appear to fit with the familiarity of the “normal” version and especially when it’s from the Golden Era of the big three Japanese brands – Citizen Casio and Seiko.

Take the unusual cased D100 Citizen Promaster Windsurfer, which unlike the standard black resin model features a metalised reshaped case with the addition of an orange/yellow outer bezel stylised colorway band around the top face.  It alters the look considerably.

Citizen D100 Surfer 1988 vintage

This one lost its original black resin strap somewhere along the years and has an alternative Casio strap, which in all honesty could easily have been the same as the original, though minus the printed wind-speed data.  A good point to note with these older vintage models is the use of standard spring bars, so alternative straps are possible, which is a plus over many current models.

The D100 model was introduced back in the late 1980’s (this one is 1988) and so far I’m unable to find a Manual for it.  However as with many of the older digital models it’s fairly intuitive and the basic timekeeping functions are easy to work out and operate.  This model has a Memo function so Stopwatch events (I think 5) can be stored in memory and recalled later.  I have another Citizen model with this function which may be similar (mod 948).
On this model it appears the module and all functions appear to be working as they should, which is so important when collecting these old models.

And as with many of these old Citizen and Casio models the term “Windsurfer” was basically a marketing description to attract those looking for a “complication” digital watch.  Calculations as such, were limited to printed data tables on the original rubber strap, such as wind-speed/velocity etc.  However the watch is conventional in that it features a fairly standard function set.

Function-wise – it states them quite clearly on the dial in white lettering – Alarm, Timer, Stopwatch and Memo and the Time (hours, minutes and seconds), Day, Date and Month are running indications.  There is also a colored mobile display in green and red showing seconds, with additional segments of 10, 20 and 30 second and a running 5 seconds are indicated in small blocks in a mobile green display and the collective times in red segments – so an interesting display even in standard timekeeping mode.  The lower Time and Calendar digital dial contrast is exceptional for the vintage and is very easy to read.

This model also has a 100m Water Resistance courtesy of a flat, steel 4 screw back plate, though being a vintage model I have not tried it out and don’t intend to either.

Flat steel screwed back plate = 100m Water Resistance (Serial No. brushed out)

But why is the D100 so difficult to find compared with the D060 or D120? – I have no real answer for that, but as a collector the attraction for me is perhaps just that very fact.  I have seen a few of them before, though not in great condition, but also a long way from the UK, South America and Southern Europe as I recall.

And that’s the thing about older digital vintage model variations, and there’s lots of ’em, that when you do come across one, you might have to do a bit of investigation to find specific or indeed any relevant information.  The production date isn’t too difficult if you have an idea of the decade the model came out – the model number indicates the Year and the Month and even the number of pieces produced.
But other than that, more often than not you don’t find much else with vintage digitals and sometimes you can draw a blank.  In this instance there’s no indication of any Module No. which is a pity. (I’ll probably remove the back soon and see what’s stamped there).

Generally though this lack of data is a real a shame as many of these models were variants resulting from a period when new modules and new technology were appearing almost daily and are the precursors of many of today’s current models.

Anyway lack of information or not, I like this particular model as it’s different from the usual ones which could often scuff easily, whereas this metalized case seems that little bit harder and as a result is looking great and almost as new.

Indeed it can be a fascination in itself collecting even just one model from a brand such as Citizen, as they were definitely front runners in both the technology and the display of data in watches at an exciting time in digital watch development.
I know a few guys who specialise in just that and one or two have almost every version of the same model covering many years of development.  Now I’m not quite as obsessive yet but I have done a little of that myself in the collection of Casio Compass function watches from the early 1970’s onwards.  It showed me for example that the compass functions themselves haven’t improved much over the intervening years until the advent of the triple axis compass.

Even then it was more to do with functionality than accuracy.  (The need for keeping the compass flat and steady was no longer required).   I say that as I’d still put up some of the older twin axis models against triple axis and if used properly I wouldn’t guarantee which would be the most accurate.

So another vintage digital joins my little collection and I have more ready to Post once I’ve time to take the pictures.  Three Casio multi-display models from the Golden Age that are in excellent condition and operating as well as they did when bought new.