In the early 1970s Citizen were making a range of high quality automatic mechanical and electro-mechanical watches as their production development reached its peak, just before the introduction of mass produced quartz models transformed the landscape. An example of Citizen’s expertise and innovation is the ‘Adorex’ line – especially those models with the 25 jewel 8000/8001 movement (technically the 8000A/8001A, but I don’t believe any other variants were made).
The Adorex models used two movements, during only a short production run starting in 1974 – the 8000 and the 8050. But it is the 8000 movement that is of greatest interest, since it has a unique feature not seen in any other model before or since, as far as I know….
Firstly here’s my example, which has a sparkling white dial in an otherwise conventionally designed stainless steel case:
The 8000 movement was the first to use a rotor which wound in one direction, which became the standard design a year or so later in the ubiquitous 8200 movement – the movement number is clearly stamped on the back, with a production date of February 1974:
Here’s the movement, with the arrow on the rotor showing the winding direction – these are high-beat, running at 28,800 beats per hour:
But uni-directional winding is not the unique feature….you may have noticed that there is no conventional fine adjuster on the balance, but there is a lever which locates in a slot:
And this is the unique feature of the 8000 Adorex – since this lever, which allows fine adjustment of the hairspring, is connected to the crown. So this allows regulation of timing without opening up the watch – it is activated by pulling the crown out to a third step, beyond time setting position, as seen in this scan of the instructions:
Pulling the crown out to the regulation position is not easy, it takes some force, presumably to avoid accidental activation. Here’s a video of the feature in use, with the back removed to clearly show what happens:
The design was probably not deemed to be too practical – the degree of movement for regulation is necessarily small, and not being able to see the gear as it is moved would make it difficult to use without removing the case back. So it’s an innovation that was only seen in this model and therefore short-lived – yet fascinating to see and now to have in the collection.
And remember, if you are looking to acquire one of these, it is only found on the 8000/8001 movement, whilst the 8050 Adorex’s have the conventional type of fine adjuster.