The movement used in the early Polarouter and Polerouter models was the caliber 138 SS. It was introduced by Universal Genève in 1948, first as cal. 138 with a subsidiary second and then with a central second as cal. 138 SS and with date indication as cal. 138 moondate. The cal. 138 SS measures 28.2 mm in diameter and 5.55 mm in thickness. Its balance makes 18,000 vibrations per hour. As in all early self-winding wrist watches, the weight - located in the center of the movement - oscillates between two springs acting as shock absorbers, the so-called bumpers. This mechanism is only winding the mainspring during one motion. The bimetal 2-arm balance with compensating screws is protected by an Incabloc antishock system. It is fitted with a flat Nivarox hairspring. The balance cock has a long regulator pin. The cal. 138 SS has 17 jewels, a plain surface finish and is rhodium-plated. It is shock-proof and anti-magnetic. Despite the precision and reliability that was proven on duty for SAS, the movement was replaced by the famous "Microtor" movement after approximately one year of production.  

Caliber 138 SS: Bumper automatic movement, 17 jewels

Caliber 215: First Microtor automatic movement, 28 jewels

In the early fifties Universal Genève masterminded, parallel to the Buren Watch Company, a radically new automatic winding system: the Microtor with its incorporated rotor mass. The Patent for the technical design was applied on 27th May 1955 and, after some legal troubble, registered on 15th May 1958 under the No. 329805. Therefore, the movements of the first production years are signed "Patented Rights Pending" underneath the rotor. The first movement introduced in spring 1955 was the cal. 215. The rotor is winding the mainspring in both directions, enabling more energy to be stored. The main characteristics are: 28.0 mm diameter, 4.1 mm height, 18,000 vibrations per hour, 28 jewels. The 2-arm monometallic balance is protected by an Incabloc antishock system. The self-compensating flat Nivarox hairspring is blue coloured. The escape wheel is fitted with a Gyrocap shock-protection. The regulator is very short and arrow-shaped; since 1958 a long shaped regulator was used. The power reserve of 60 hours is exptional high. The rotor is pink gold-plated with a "Colimaconnage" finish, the movement rhodiumed with a fine "Fausses cotes de Genève" decoration.

In 1958 the cal. 215-1 with a date indication at the "3" followed. The movement was introduced in a chronometer version of the Polerouter Date. It was supplied with a screw driven fine-regulator of the balance spring, that was not available in the "normal" cal. 215-1 or in the thinner later cal. 215-2, where a long shaped regulator was used. Due to the additional date indication module the movement grew in thickness by 1.15 mm to 5.15 mm, all other features remained unchanged. In the same year the cal. 215-07 without date, 4.7 mm high and 17 instead of 28 jewels was launched. The cal. 215-9 also without date indication but with 28 jewels, has an increased frequency of 21,600 vibrations per hour, whereas the cal. 215-97 had the same features with just 17 jewels. The other variations, cal. 215-17 with date indication but only 17 jewels and the cal. 215-27 with the same number of jewels but a reduced thickness of 4.7 mm due to a integrated date function, were not or only very seldom used in Polerouter models.  

Caliber 215-1: Microtor movement with longer regulator, 28 jewels

Caliber 218-2: Microtor movement with micrometric regulator, 28 jewels

The sucessor of the cal. 215 are the cal. 218 and 218-2, whereas only the cal. 218-2, fitted with a date indication, was used in the Polerouter (Polerouter Date). Introduced arround 1960, it replaced all calibers of the type 215. Only for some rare models without an date indication like the Polerouter Sub with two crowns, the cal. 215 was still used. The thickness could be reduced to 4.7 mm due to the integration of the date function. The general technical features and the finish remained unchanged. The movement now has the same micrometric adjustment of the balance spring as the above mentioned cal. 215 (chronomètre). Furthermore, it is featuring several innovations in parts of the automatic mechanism. For example, on 30th January 1957, Universal Genève lodged an application for Patent No. 330900, refering to a further development of the winding mechanism. The cal. 218-9 has an increased balance frequency of 21,600 vibrations per hour, 28 jewels but no date. It was used in some late Polerouter Genève models.

The next stage of development is the cal. 69. The movement is featuring an even more advanced winding system. While the general design and seize remained the same, the rotor has a new shape. In addition, several parts are also given the "stop oil" treatment, in order to reduce their need for lubrification. The movement was introduced arround 1962 in the Polerouter Date and later used in the Polerouter Super. The version 1-69, for example used in the Polerouter Sub (with a revolving lunette), has 17 or 28 jewels and no micrometric adjustment for the balance spring. The cal. 68 is identical but without date indication, was only used seldom for the Polerouter familiy. The cal. 69 is the last representative of the classical microtor movements, originating from the famous cal. 215. The sucessors cal. 66 (without second hand), cal. 67 (without second hand but with date), both not used for Polerouter models, are thinner (only 2.5 mm without date) but less attractive. This is due to the less harmonious arrangement of the bridges and the reduced number of jewels (25 instead of 28), because of a rotor with a ball bearing.  

Caliber 69: Microtor movement with new rotor mechanism, 28 jewels

Caliber 72:
Microtor movement with new design, 25 jewels, 21,600 A/h

The cal. 72 with a diameter of 27.0 mm instead of 28.0 mm, is completely different from the aforementioned movements. It has a date and weekday indication at the "3" and a height of 4.6 mm. The frequency increased to 21,600 vibrations per hour (like with the cal. 215-9, cal. 215-97 and cal. 218-9) while the number of jewels was reduced to 25. This is related to the use of a ball bearing for the rotor mechanism. The arrangement of the bridges differs very much from the classical microtor movements (cal. 215, cal. 218-2, cal. 69). The cal. 72 was used in all Polerouter models with separate windows for day and date in the late sixties. The thinner cal. 71 (3.9 mm) without the weekday indication was not used for Polerouter models. The so-called "Super Microtor" cal. 256 (with the ending A, B or C) is not covered here deliberately. The movement has a "normal" central rotor and was produced by Movado (equivalent to cal. 395). It has 28 jewels but is of lower quality and only used in the Polerouter compact. Furthermore, all electrical or Quartz movements are ignored here.

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Service instruction 1
Microtor cal. 215
- overview -

Service instruction 2
Microtor cal. 215
- rotor system -
Service instruction 3
Microtor cal. 215
- central second -
Service instruction 4
Microtor cal. 215
- clutch and barrel -