Although Citizen’s first (and now rare!) automatic watch used the familiar ‘swinging’ or ‘oscillating’ weight type of rotor when it was launched in 1958, the company designed and used its own circular geared rotor in the early to mid-1960s. It used this design in the ‘Jet’ and ‘Super Jet’ models, and it is known as the ‘Jet rotor’.
In the mid-1960s the Jet movements were dropped in favour of swinging weight designs – I have read somewhere that the Jets were a little less reliable, but I’m not sure if this was actually the case. Perhaps more important was the trend to slimmer designs to which the swinging weight was better suited.
The Jet movements all ran at 18,000 beats per hour, and generally can be hand wound – the exceptions (as far as I know) being the 0320/0321 and 1130/1/2/3 movements with 17 and 19 jewels. This includes the ‘Rookie’ models, some of which have small, recessed crowns as a result. I’m not sure at this stage whether the 1120 movement with 19 jewels has hand winding or not.
Some movements had an ‘Easy Change’ quick set mechanism for the date, which involves pulling the crown in and out when in the time setting position – this has the disadvantage that the date can be accidentally changed if the crown is pulled a little too hard when the time has to be adjusted. As far as I know, all the later (41xx) movements had the Easy Change feature as well as hand winding capability.
The later models had day windows, which can only be set by winding back and forth between 12 and 9.
The Jet models are all part of the ’03’ movement ‘family’, which comprises three groups starting with the 03xx models first seen in October 1961, followed by the 11xx (January 1962) and completed by the 41xx (1964). Interestingly this last group includes one hand winding model – the Seven – which uses the 23 jewel 4000 movement (see here for a look at that one: https://sweep-hand.org/2011/06/29/this-weeks-featured-watch-9-the-seven/)
NB: The ‘Seven’ description on these models, and indeed on other lines, for example the Crystal Seven, appears to be used where both day and date windows are present.
The movements look pretty well the same, and I had originally thought that the 41xx calibers could be identified by having just four screws on the rotor, compared with six on the earlier 03xx and 11xx versions. That was based on the Museum book which only shows 4 screwed rotors in the 41xx section – my Monthly (4120) model also has 4 screws. However I have seen a number of 41xx models since with six screws which look authentic and have correctly marked rotors (e.g. ‘Autodater Seven’), so it now appears that either variant can be correct:
Before summarising the movements and models, here’s a quick video showing how the rotor moves, it winds in both directions: http://s282.photobucket.com/albums/kk252/Sweephand/Jet%20Auto%20Dater%2017j/?action=view¤t=MVI_0537.mp4
The following summary is correct to the best of my knowledge at the moment – I’ll add and amend if and when other / more information comes to light.
Movement & Model Summary:
Movement # Model Name(s) Jeweling Date/Day First Production
0310 Jet Automatic 21, 23, 25 None October 1961
0320, 0321 Jet Rookie 17, 19 None 1962
0340, 0341 Super Jet, Super Precision 35 None 1963
1120, 1121 Jet Auto Dater, Newmaster, 19, 21, 23, Date January 1962 120m, Para200mWater 27, 35
1130, 1131, Jet Auto Dater, Rookie, 17, 19 Date 1962 1132, 1133 Para400Water, 40m
1150 Super Jet Auto Dater, 39 Date 1963 Super Auto Dater 80m/150m
1160, 1161 Super Jet Auto Dater 39 Date 1963 (Easy Change)
1170 Jet Auto Dater 27 Date 1962 (Easy Change)
4101, 4102, 4103 Auto Dater Seven, 40m 25 Date & Day 1964
4111, 4112, 4113 Auto Dater Seven, 40m, 19 Date & Day 1964 Ceto
4130 Auto Dater Seven , 40m 35 Date & Day 1964
4120, 4121 Auto Dater Seven Monthly 19 Date, Day & Month 1964
(NB: I think all 41xx movements had ‘Easy Change’ quick set for date)
0310, 0320/1, 0340/1 29.00mm 4.65mm
1120/1, 11300/1/2/3 29.00mm 5.00mm
1150, 1160/1, 1170 29.00mm 5.34mm
All 41xx Movements 29.00mm 6.39mm
If you’re interested in the architecture of the movement, here are schematics showing how it is put together.
Schematic 1 -Rotor Side:
Schematic 2 – Dial Side (11xx Variants):
Schematic 3 – Dial Side (41xx Variants, excluding ‘Monthly’):
Here are just a few examples to illustrate the range of models that used the Jet movements, with acknowledgement to sellers on Yahoo Japan for the images:
Auto Dater 7:
Auto Dater 7:
Some models have special case backs, e.g.:
Auto Dater 7:
And finally from my own collection:
1120 Auto Dater:
1130 Auto Dater:
4101 Auto Dater 7: