Seiko Grand Quartz tutto originale 9943-8020

Descrizione

Dalla mia collezione privata vendo stupendo Seiko Grand Quartz termocompensato. Prodotto Jdm dell'aprile 1969. MovementTwin Quartz Caliber9943 DialDiamond Dust Case36x42x11mm SteelLugs18mm BraceletBB240 16,5cm Crystal serial #300WB4GN00 Sapphire Timegrapher Accuracy:+0,3spd Jewels9 Condition Excellent Service Not required Box & Papers: No box No papers Twin Quartz Craze When quartz was well established, at the end of the Seventies, the Seiko 1978 JDM catalogue showed the twin quartz caliber for the first time, however there were (eventually) at least three different design technologies behind the Seiko twin quartz models. While quartz based watches are extremely accurate compared to mechanical watches, they are still not perfect. One of the main reasons for the inaccuracy in a quartz model is because as the temperature changes the oscillation of the quartz crystal varies slightly. This change in oscillation will cause the slight drift in timing. To compensate for these changes quartz watches will employ some kind of temperature compensation to maintain a steady oscillation. Seiko Kings with the two oscillators are very interesting watches. Very accurate as you might expect from two time sources (crystals) and thermocompensation. In this small and rather inexpensive group of high end quartz models the oldest (probably before 1978) thermocompensation method is the one present in the King Quartz caliber - the method is based on having two quartz crystals both around 32 kHz and using the difference from them as a way to indirectly measure temperature - and from that the number of quartz ticks that need to be skipped in order to achieve a better accuracy The five calibers In all five different calibre series were introduced in less than two and a half years, they were used in the Superior, Grand, King and Quartz line ups.

Il venditore dichiara che il bene oggetto del presente annuncio è originale.