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It's described as a 21 jewel Sea Gull movement with day/date.
Ok; now I remember :-d I nshould have twigged when I saw the micro adjuster on the regulator lever.It looks like a manual winding ST-7 to me.
From what i remember the idea was to make a high end watch for export but the production costs were high enough that they would have to price it at a similar level to swiss watches in order to make money. after the st7 project was canceled they cased up the watches and gave them away to employees. I have always thought of the manual version as a separate watch rather than just missing parts especially since seagull used different bezzels for automatics and manuals (silver for auto, gold for manual) but who knows.What would be the reason for making these watches? Export versions in the time that some patents were (willingly or unwillingly) violated?
That is unlikely. The ST5D uses an auto-winding system originally patented by Eterna, but the patent would probably have lapsed in the 1960s at the very latest. Likewise the ST7 uses the Felsa system, the patent for which would have lapsed at a similar time. In fact the Soviet-built Poljot 'Orbita', using the same system, was being sold internationally by the mid 1960s.What would be the reason for making these watches? Export versions in the time that some patents were (willingly or unwillingly) violated?