Calibres Seiko

Movt. #	Prefix #	Winding	Model Name	Model #	Jewels	Made Year	Made Loc.	Diam; Thick	Beats/sec
10	A	Hand	10Solar	10S	19		D	15.5 x 13; 3.5t	5.5
10	B, C	Hand	10Solar	10S	17 - 21			15.5 x 13; 3.5t	5.5
10	M	Hand	10Solar	10S	17			15.5 x 13; 3.5t	5.5
10	04A,B	Hand	10Angel	10AN	21			15.5 x 13; 4.4t	5.5
10	04C	Hand	10Angel	10AN	17 - 21			15.5 x 13; 4.4t	5.5
10	04D,M	Hand	10Angel	10AN	17			15.5 x 13; 4.4t	5.5
10	20A,B,C	Hand	10QueenSeiko	10QS	23	1964	D	15.5 x 13; 3.5t	5.5
10	40A	Hand	10Solar Special	10SL	23			15.5 x 13; 3.5t	5.5
11	A	Hand	11Solar	10S	17 - 21
11	04A	Hand	Salvia	SV	17 - 21			15.5 x 13; 4.4t	5.5
11	20A	Hand	11Queen Seiko	11QS	23	1970	D	15.5 x 13; 3.5t	6
11	20A	Hand	Belfina/11Queen Seiko Special	11QSL	23
11	40A	Hand	11 Solar Special	11SL	23
11	44A	Hand	Salvia Special	SVL	23
15	A	Hand	Lady Seiko	LS	21	1959	D	19.6 x 12.9; 3.5t	6
15	20A	Hand	Fine Seiko	FS	17			19.8 x 9.6; 3.5t	5.5
15	20B	Hand	Fine Seiko	FS	17 - 23
17	A	Hand	Seiko1700	1700	17			∅13.5; 3.2t	6
17	A	Hand	17Queen Seiko	17QS	17
17	A	Hand	17Queen Seiko Special/17 Belfina	17QSL	20	1969	D
175		Hand	Sportsman		15	1960	S
18	A	Hand	Universe	UN	21	1960	D	∅13.5; 3.0t	5.5
18	B,M	Hand	Universe	UN	17
19	A	Hand	Venus	VE	17	1960	D	19.6 x 12.9; 3.5t	6
19	04A	Hand	19Venus	19VE	17 - 23			19.6 x 12.9; 3.5t	8
19	20A	Hand	Venus Special	VEL	21
19	44A,B	Hand	Seiko High Beat Chronometer 36000	1944
19	44B	Hand	Seiko High Beat Chronometer	19CM	23	1967	D	19.6 x 12.9; 4.4t	10
19	64A	Hand	19 Grand Seiko	19GS	23	1968	D	19.6 x 12.9; 4.4t	10
19	84A	Hand	19 Grand Seiko High Beat V.F.A.	1984	23	1972	D	19.6 x 12.9; 4.4t	10
205		Hand	Harmony	HA	19	1961	S
21	A,C	Hand	Sports Lady 17	SLS	17	1961	D	17.8 x 15.3; 3.5t	5.5
21	D	Hand	Sports Lady 17	SLS	17
21	02A,C	Hand	Sports Lady 17 Calendar	SLSC	17
21	04A,B	Hand	Chorus	CR	17	1961	D	17.8 x 15.3; 4.4t	5.5
21	05A	Auto	Matic Lady Calendar	MALC	21
21	07A	Hand	Chorus Calendar	CRC	17 - 21
21	07B	Hand	Chorus Calendar	CRC	17 - 21 - 23
21	17A	Hand	Chorus Calendar	CRC	17
21	18A	Hand	21 Chorus Calendar	21CRQ	17 - 21 - 23
21	19A,B	Hand	Chorus Weekdater	CRW	21
21	40A	Hand	Seiko 2140	2140	21
21	60A	Hand	School Time	21ST	17
22	01A	Auto	Seiko 2201	2201	17
22	02A	Hand	22 Chorus Calendar Echo	22CRE	17 - 21
22	02A	Hand	22 Chorus Calendar Special	22CCL	23
22	05A	Auto	22 Matic Lady Calendar	22NLQ	17 - 21	1970	D	∅17.2; 5.7t	8
22	05A	Auto	22 Matic Lady Calendar Special	22MSL	25
22	06A	Auto	22 Matic Lady Weekdater	22MLW	17 - 23
22	06A	Auto	22 Automatic Weekdater	22ATW	17 - 23
22	20A	Hand	Seiko 2220	2220	17 - 24
22	42A	Hand	22 Chronometer	22CM	23	1971	D	∅17.5; 5.8t	8
22	45A	Auto	22 Automatic Chronometer Calendar	22ACM	25
24	06A	Hand	2Matic Lady Weekdater	24MLW	23
24	09A	Hand	Seiko 2409	2409	23
24	11A	Hand	Seiko 2411 ECharriot	2411	23	1972	D
24	15A	Hand	Seiko 2415	2415	23
24	18A	Hand	Seiko 2418	2418	23
24	19A	Hand	Seiko 2419	2419	23
24	21A	Hand	Joyfull Special	2421	23
24	26A	Hand	Joyfull Special	2426	23
24	31A	Hand	Bellfina Seiko 2431	2431	25
24	25A	Hand	Bellfina Seiko 2435	2435	25
245		Auto	Sportsmatic	SMA	17 - 19	1961	S
2451		Auto	Sportsmatic	SMA	17 - 19
24	66A	Auto	Joyfull Special	2466	25	1974	D	∅19.4; 4.3t	8
25	01A,B,C	Auto	25 Seikomatic Lady	25MAL	17	1965	D	∅17.5; 5.3t	5.5
25	02A	Hand	Chorus Calendar Special	CRCL	17 - 23	1964	D	∅17.5; 5.5t	5.5
25	05A,B	Auto	25 Seikomatic Lady Calendar	25MLC	21
25	15B	Hand			17
25	16B	Auto			21
25	17A,B	Auto	25Seikomatic Lady Calendar	25MLQ	17 - 21	1965	D
25	18A,B	Hand	25 Chorus Calendar Special	25CCL	23
25	18B	Hand	25 Chorus Calendar Echo	25CRE	17 - 21
25	19A,B	Hand	25 Queen Seiko 2519	2519	23	1965	D	∅17.5; 3.2t	5.5
25	39A	Hand	25 Queen Seiko Special	2539	25	1966	D	∅17.5; 3.2t	5.5
25	59A	Hand	25 Queen Seiko High Beat	2559	24	1968	D		8
25	65A	Auto	25 Seikomatic Special	25MSL	25
270		Auto	Maticlady		21	1960	S	18.4 x 15.3; 5.7t	5.5
27	06A	Auto	27 Maticlady Weekdater	27 MLW	17 - 21	1970	D	∅17.5; 5.7t	8
290		Hand	Gyro Marvel	GM	17	1959	S
2906		Hand	Joyfull		17 (21)	1976	D	∅18.4; 5.3t	8
3140		Hand	Seikoliner		21	1960	S
3180		Hand	Grand Seiko (first model)	GS	25	1960	S
330		Hand	Queen Seiko		23	1962	D	18.4 x 15.3; 3.5t	5.5
341		Hand	Crown Special	CWL	23	1961	S
375		Hand	Disney Time		7	1961	S
394		Auto	Seikomatic Selfdater	MAS	24	1962	S
395		Auto	Seikomatic Selfdater Quick Set	MASK	24
400		Auto	Matic Weekdater	MAW	33
40	05A	Auto	Seiko Bellmatic Calendar	40BC	27
40	06A	Auto	Seiko Bellmatic Weekdater/Business Bell	40BW	17 - 27	1967	S	∅31.2; 7.1t	5.5
402		Hand	Skyliner	SLN	21	1961	S
410		Auto	Sportsmatic 5	SMA5	21	1963	S
430		Hand	Grand Seiko Weekdater	GSS	35	1963	S
436		Hand	Sportsman 17	SMS	17	1960	S
4361		Hand	Sportsman 17	SMS	17	1960	S
44	A	Hand	44 King Seiko Quick Set	KSK	25	1964	D	∅26.0; 4.4t	5
44	02	Hand	44 King Seiko Calendar	KSSK	25	1965	D	∅26.0; 4.8t	5
44	20A	Hand	44 Grand Seiko/44 King Seiko Chronometer	44GS - EKSCM	27	1964	D	∅26.0; 4.4t	5
44	20B	Hand	44 Grand Seiko/44 King Seiko Chronometer	44GS - EKSCM	27	1964	D
45	00A	Hand	45 King Seiko	45KS	25		D	∅27.4; 3.65t	10
45	00A	Hand	45 King Seiko Chronometer	45KM	25			∅27.4; 3.65t	10
45	02A	Hand	45 King Seiko Calendar	45KSC	25	1969	D	∅27.4; 3.65t	10
45	02A	hand	45 Grand Seiko Observatory Chronometer	45KCM	25			∅27.4; 3.65t	10
45	20A	Hand	45 Grand Seiko V.F.A.	45GS	25	1968	D
45	22A	Hand	45 Grand Seiko Calendar	45GSC	25	1968	D	∅27.4; 3.6t	10
45	80A	Hand	45 Grand Seiko V.F.A.	4580	25	1969	D	∅27.4; 3.65t	10
45	82A	Hand	45 Grand Seiko Neuchatel Observatory Chronometer	45GSN	25	1969	D	∅27.4; 3.65t	10
460		Hand	Liner Chronometer	LNCM	25	1963	S
4S		Auto	Revised Cal. 52			1992	D
50	00	Hand	Tomony		7	1970	S	26.0 x 25.5; 4.4t	6
50	02	Hand	Tomony School with Date		7	1970	S	26.0 x 25.5; 4.8t	6
50	05	Auto	Tomony Automatic		7	1970	S	26.0 x 25.5; 6.4t	6
50	18	Hand	Tomony Seagull Digital Display		7	1974	S	26.0 x 25.5; 5.9t	6
50	C	Hand	Disney Time		17	1973	S
51	05							∅26.0; 4.9t	5.5
51	06A	Auto	51 Matic Weekdater	51MW	33	1967	D	∅26.0; 4.9t	5.5
51	25							∅26.0; 5.3t	5.5
51	26A	Auto	51 Seiko 5 (DX)	51-5	23	1967	D	∅26.0; 5.3t	5.5
51	39A	Auto	51 Seiko 5 (DX)	51-5D	27		D	∅26.0; 5.3t	5.5
51	45							∅26.0; 5.3t	8
51	46A	Auto	51 Seiko Pressmatic Weekdater	51PMW	27 - 30	1969	D	∅26.0; 5.3t	8
52	05							∅26.0; 3.9t	8
52	06A	Auto	52 Loadmatic Special Weekdater	52LMW	23 - 25	1969	D	∅26.0; 3.9t	8
52	16A	Auto	52 Loadmatic Special Weekdater	52 LWL	23 - 25
52	45A	Auto	52 King Seiko Chronometer (Calendar)	52KCM	25	1971	D	∅26.0; 3.9t	8
52	46A	Auto	Seiko Vanac	52KWL	25	1973	D	∅26.0; 3.9t	8
52	46A	Auto	52 King Seiko Chronometer Weekdater	52KWM	25	1971	D	∅26.0; 3.9t	8
52	56A	Auto	Seiko Vanac	52KWL	25	1973	D	∅26.0; 4.2t	8
54	A	Hand	Chronos	C	17 - 21 - 23	1958	D	∅26.0; 4.0t	5
560		Hand	Crown	CW	19 - 21	1959	S
56	01A	Auto	56 Loadmatic	56LMA	23	1968	S
56	05A	Auto	56 Loadmatic Calendar	56LMC	25			∅26.0; 4.3t	6
56	06A	Auto	56 Loadmatic Weekdater	56LMW	23 - 25	1968	S	∅26.0; 4.3t	6
56	19A	Auto	56 Seiko Duotime	56DMC	25			∅26.0; 4.2t	6
56	21A,B	Auto	56 King Seiko	56KA	25	1969	S
56	25A,B	Auto	56 King Seiko Calendar	56KAC	25	1968	S	∅26.0; 4.5t	8
56	26A,B	Auto	56 King Seiko Chronometer (Calendar)	56KCM	25	1968	S	∅26.0; 4.5t	8
56	26A,B	Auto	56 King Seiko Weekdater	56KAW	25	1969	S	∅26.0; 4.5t	8
56	21A,B	Auto	56 King Seiko Chronometer Weekdater	56KWM
56	26B	Auto	Seiko Vanac	56KAW
56	41A	Auto	56 Grand Seiko	56GA	25
56	45A	Auto	56 Grand Seiko (Calendar)	56GAC	25	1970	S	∅26.0; 4.5t	8
56	46A	Auto	56 Grand Seiko Weekdater	56 GAW	25	1970	S	∅26.0; 4.5t	8
57	B	Hand	Crown	CW	21			∅28.0; 4.7t	5
57	17A	Hand	Crown Chronometer (Calendar)	CWCGC	21	1964	S	∅28.0; 6.1t	5
57	18A	Hand	Countgraph (Olympic LE)		21	1964	S	∅28.0; 7.3t	5
57	19A	Hand	Crown Chronograph	CWCG	21	1964	S	∅28.0; 6.1t	5
57	20A	Hand	Grand Seiko	GS	25	1960	S	∅28.0; 4.4t	5
57	22A	Hand	Grand Seiko Selfdater	GSS	35	1963	S	∅28.0; 4.7t	5
57	22A,B	Hand	Grand Seiko Calendar	57GSC	35	1963	S	∅28.0; 4.7t	5.5
57	40A	Hand	57 Load Marvel (Engraved Numerals)	LMK	23	1964	S	∅28.0; 4.4t	5
57	40B	Hand	57 Load Marvel (Applied Seiko Logo)	LMK	23		S	∅28.0; 4.4t	5
57	40C	Hand	57 Load Marvel 36000	LM36	23	1967	S	∅28.0; 4.4t	10
57	60	Hand	Crown Special	CWL	23	1961	S	∅28.0; 4.4t	5
57	80	Hand	Skeletonized Watch		19	1981	S	∅28.6; 4.1t	6
57	A	Hand	Crown Selfdater		21	1961	S
603		Auto	Seikomatic	MA	17 - 20 - 21 - 30	1963	S
60	M	Hand	Gold Feather	GF	17 - 25	1960	D	∅27.0; 2.9t	5
61	A	Hand	61 Skyliner	61SLN	17 - 21	1968	S	∅27.4; 3.5t	6
61	02A	Hand	61 Skyliner (Calendar)	61SLC	17 - 21
61	05A	Auto	61 Diver (150m)	61MC	17	1968	S	∅27.4; 5.1t	5
61	05B	Auto	Seiko Diver (Hack Second)	61MC	17			∅27.4; 5.1t	5
61	06A	Auto	61 Seiko 5DX	61-5D	25	1967	S	∅27.4; 5.1t	5
61	06B	Auto	61 Seiko 5DX	61-5D	17 - 25	1967	S
61	06C	Auto	61 Five Actus	61-5A	17 - 23 - 25	1967	S
61	06C	Auto	Seiko Advan	61AD	17 - 23 - 25	1967	S
61	10A	Hand	61 Railroad Watch	61RW	21	1971	S	∅27.4; 3.5t	6
61	17A,B	Auto	61 Worldtime	61WT	17	1968	S	∅27.4; 5.1t	6
61	17A	Auto	61 Navigator Timer	61NT	17			∅27.4; 5.1t	6
61	19A,B,C	Auto	6Seiko 5 Sports	61-5	21	1970	S	∅27.4; 5.1t	5
61	38A,B	Auto	Seiko 5 Sports Speedtimer	61SPH	21	1970	S
61	38A,B	Auto	Seiko Chronograph	61CHW	23			∅27.4; 7.9t	6
61	39B	Auto	Fine Sports Speedtimer	61SPM	17	1969	S	∅27.4; 7.1t	6
61	39B	Auto	Fine Sports Speedtimer	61SPM	21	1969	S	∅27.4; 6.5t	6
61	45A	Auto	61 Grand Seiko Calendar	61GAC	25	1968	S	∅27.4; 5.6t	10
61	46A	Auto	61 Grand Seiko Weekdater	61GAW	25	1968	S	∅27.4; 5.6t	10
61	55A	Auto	61 Grand Seiko Special (Calendar)	61GBC	25	1971	S
61	56A	Auto	61 Grand Seiko Special Weekdater	61GWL	25	1970	S	∅27.4; 5.6t	10
61	59A	Auto	Professional Diver 300 /61 Matic	6159	25	1967	S	∅27.4; 5.6t	10
61	59B	Auto	Professional Diver 600	6159	25	1975	S	∅27.4; 5.6t	10
61	85A,B	Auto	Grand Seiko V.F.A. (specially Adjusted)	6185	25	1969	S	∅27.4; 5.6t	10
61	86A	Auto	Grand Seiko V.F.A. Weekdater (specially Adjusted)	6186	25	1972	S
62	00	Hand	Seiko Liner	LN	23 (21)	1960	S	∅26.0; 3.3t	5
62	01B	Auto	Seikomatic/Matic Silverwave	MA	20	1960	S	∅28.0; 4.7t	5
62	05B	Auto	Matic Selfdater	MAS	17 - 24	1962	S	∅28.0; 5.3t	5
62	06A,B	Auto	Seiko Business/Matic Weekdater	62B-MAW	26	1963	S	∅28.0; 5.6t	5
62	15A	Auto	Seiko Professional Diver 300	6215	35	1967	S
62	16A	Auto	Matic Weekdater	62MWK	39			∅28.0; 5.6t	5
62	17A	Auto	Seiko Matic Divers Watch	62MAS	17	1964	S	∅28.0; 5.3t	5
62	17A	Auto	Seiko Matic Worldtime	MASWT	17	1964	S
62	18A,B,C	Auto	Seikomatic Weekdater	MAWK	35	1964	S	∅28.0; 5.6t	5
62	20M	Hand	Skyliner	SLN	17	1961	S	∅24.1; 3.8t	5
62	20B,C	Hand	Skyliner	SLN	21			∅24.1; 3.8t	5
62	20D	Hand	Skyliner	SLN	17 - 21			∅24.1; 3.8t	5
62	22M	Hand	Skyliner Calendar	SLNC	17			∅24.1; 3.8t	5
62	22A,B	Hand	Skyliner Calendar	SLNC	21			∅24.1; 3.8t	5
62	22C	Hand	Skyliner Calendar	SLNC	17 - 21			∅24.1; 3.8t	5
62	40	Hand	Liner Chronometer		25	1963	S	∅26.0; 3.5t	5
62	45A	Auto	62 Grand Seiko/Seikomatic Chronometer	62GAC-H	35	1966	S	∅28.0; 5.6t	5.5
62	46A	Auto	62 Grand Seiko Weekdater/62Matic Weekdater Chronometer	62GAW-H	39	1966	S	∅28.0; 5.6t	5.5
63	06	Auto	5 Actus		21	1976	S	∅27.4; 5.2t	6
63	09	Auto	Export Models Only		17	1976	S	∅27.4; 5.2t	6
63	10	Hand	63 Railroad Watch		17	1976	S	∅27.4; 3.4t	6
63	47	Auto	Moonphase (Only for Export)		23	1986	S	∅27.4; 5.8t	6
66	A,B	Hand	Sportsmen 17	SMS	17	1960	S	∅24.1; 3.8t	5
66	01A	Auto	Sportsmatic	SMAC	17 - 19	1961	S	∅28.1; 5.4t	5
66	01B	Auto	Sportsmatic	SMAC	17 - 19			∅28.1; 5.4t	5
66	02B	Hand	Sportsmen 17 Calendar	SMSC	17		S	∅28.1; 5.4t	5
66	05	Auto	Sportsmatic Calendar		19	1962	S
66	06B	Auto	Sportsmatic 5	SMA5	21	1963	S	∅28.1; 6.4t	5
66	18A	Hand	Visually/Hearing Impaired		17	1966	S	∅24.1; 3.8t	5
66	19A	Auto	Sportsmatic 5	66SA5	21	1964	S	∅28.1; 6.4t	5
66	40A	Hand	Disney Time		7	1961	S	∅24.1; 3.8t	5
66	42A	Hand	66 Schooltime		7
66	59A	Hand	66 Schooltime Weekdater		7	1964	S	∅24.1; 4.8t	5
66	60A	Hand	Seiko 6660	6660	21			∅24.1; 3.8t	5
68	00	Hand	Thin Dress Watch	6800		1969	D	19.7 x 16.9; 1.9t	6
68	10	Hand	Seiko Dress Ultra Thin	6810		1973	D	∅20.0; 1.9t	6
6S	74	Auto	Credor Chronograph			1998	D
70	01A	Auto	Automatic		17
70	05A	Auto	Seiko Automatic Calendar	70AC	17
70	06A	Auto	Seiko Automatic Calendar		17 - 19 - 21	1973	S
70	15A	Auto	70 5 Sports Speedtimer/Time Sonar	70 SPS	21	1970	D	∅26.0; 5.3t	5
70	16A	Auto	Chronograph Automatic		17	1976	D
70	17A	Auto	70 5 Sports Speedtimer	70SP	21	1971	D
70	18A,B	Auto	70 Seiko Chronograph (Weekdater)	70CMW	23	1971	D
70	19A	Auto	70 5 Actus/Seiko Advan	70-5A/70AD	21	1969	D	∅27.4; 4.8t	6
70	39A	Auto	Seiko Advan	70ADL	21
760		Hand	Fairway	FW	21	1962	D	∅26.0; 3.7t	5
761		Hand	Fairway	FW	21
76	05A	Auto	Sportsmatic Calendar DX	76SCD	23			∅28.0; 5.7t	5
76	06A	Auto	Sportsmatic 5DX	SMA-5D	23	1964	D	∅28.0; 5.7t	5
76	19A	Auto	76 5DX	76-5D	25		D	∅28.0; 6.4t	5
76	22A,C,D	Hand	Campion/Campion860	CHC86	17	1963	D	∅28.0; 4.3t	5
76	25A,C,D,E	Auto	Sportsmatic Calendar 820	SAC82	17	1964	D	∅28.0; 5.7t	5
790		Auto	Sportsmatic Calendar	SMC	19	1962	S
810		Hand	Chronos Special	CL	23	1962	D	∅26.0; 4.0t	5
820		Auto	Sportsmatic Calendar 820	SAC82	17	1964	D
830		Auto	Seikomatic Slim	MAM	30
83	01	Auto	Seikomatic Slim	MAM	30	1963	S
83	05B	Auto	83 Seikomatic Calendar/Matic Slim Date	MAC/MAMD	30	1963	S	∅29.0; 4.5t	5
83	05C	Auto	Matic Slim Date (with hand wind)	83MC	39			∅29.0; 4.5t	5
83	06A	Auto	83 Seikomatic Weekdater/Seiko BusinessA	83MW/83BA	30	1965	S	∅29.0; 4.8t	5
83	25A	Auto	83 Seikomatic Calendar	83MC	39			∅29.0; 4.5t	5
83	46A	Auto	83 Seikomatic Weekdater/Seiko BusinessA	83MW/83BA	27		S	∅29.0; 4.8t	5
840		Auto	Seikomatic Slim Date	MAMD	30
850		Auto	Champion 850 (Alpinist)	CH85	17	1963	D	∅26.0; 3.7t	5
851		Auto	Champion	CH85	17	1963	D
860		Hand	Champion/Champion 860	CHC86	17
88	00	Hand	88 Stopwatch	88ST	7
90	11	Hand	90 Stopwatch	90ST	7			∅40.3; 6.1t	5
91	19A	Hand	Railroad Watch	91RW	15			∅41.3; 6.4t	5
956		Hand	Skyliner Calendar	SLNC	21
957		Hand	Sportsman 17 Calendar	SMSC	17
9S	51	Auto	Grand Seiko (Calendar SS Bracelet)		26	1998	D
9S	55	Auto	Grand Seiko (18k strap)		24	1998	D	∅28.4; 5.3t	8

THE VALJOUX 7750 CHRONOGRAPH

If there is a single movement ubiquitous in modestly-priced contemporary chronographs, it is the Valjoux 7750. Introduced in 1974--five years after the famed Zenith El Primero automatic--the movement has been supplied in both 21,600 and 28,800 beat versions. It uses an automatic-winding module attached to the top of the movement, winding in one direction by means of a single double-click wheel. Initially using 17 jewels, current versions run in 25. The 7750 is 13.25 ligne (30 millimeter) design, 7.9 millimeters thick.

THE CONCEPT OF COULISSE-LEVER DESIGNS

Like many contemporary chronographs, the Valjoux 7750 dispenses with the traditional column wheel for switching functions. Instead a heart piece limiter (left) is used to coordinate starting, stopping, braking, and reset functions, usually by means of two buttons in contemporary designs (the earliest coulisse-lever calibers used three buttons). The Valjoux 7750 also utilizes a concept first patented in 1941 by a watchmaker, Henri Jacot-Guyot. This is a reset-to-zero (or heart piece) lever which pivots to reassure accurate reset-to-zero of both the center hand and minute counter. Previous coulisse lever designs had not been as precise in this regard.

While the parts count of a coulisse-lever design is comparable to that of a column wheel design, the various levers and springs in the lever design require much less precision in form and materials and are much less expensive to manufacture. This--economy of manufacture--was and is the purpose of a coulisse lever caliber

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CONCLUSIONS The Valjoux 7750 expresses an aspect of Swiss engineering skill that we do not normally associate with the Swiss watch industry: economy of manufacture. The 7750 is a good representation of the new, simplified chronographs that began to appear from Ebauches S.A. (now ETA) at the beginning of the 1940s and that provided serious, usually fatal, competition to smaller manufacturers of high-grade chronographs.

The Valjoux 7750 is now used in the vast majority of mechanical chronographs produced in Switzerland, and has allowed the mechanical chronograph function in watches of modest cost. For a caliber obviously engineered from the ground up for economy of manufacture, the 7750 has proved itself a reliable and durable workhorse. Without the 7750, mechanical chronographs might be known only to the buyers of luxury watches. I wish to thank Bob Frei of the TZ Tool Shop and Frei & Borel for supplying the movement used in this review.

ETA, S.A. (Wikipedia)

ETA SA

From Wikipedia, the free encyclopedia

ETA SA

Type	Member of the Swatch Group
Founded	1856 (1793, 1896)
Headquarters	Grenchen, Switzerland
Industry	Movement manufacturing
Products	Blank watch movements
Website	http://www.eta.ch

ETA SA (full business name ETA SA Manufacture Horlogère Suisse) is a Swiss producer of mechanical and quartz watch movements. It is a wholly owned subsidiary of The Swatch Group.

Contents [hide] 1 Overview 1.1 A Brief History 2 Workhorse mechanical movements 2.1 ETA 2824-2 2.2 ETA 2892 2.3 The Omega Co-axial based upon an ETA movement 2.4 Valjoux 7750 3 Monopoly allegations and investigations 4 References 5 External links

[edit]Overview

ETA SA is a Swiss producer of mechanical and quartz watch movements. It is a wholly owned subsidiary of the Swatch Group. The company specializes in the production of ébauchemovements which are used in a number of mechanical watches. ETA has owned several important Swiss watch movement companies including Valjoux, Peseux (see:[2] ) (and [3](translation) and Lemania, for a number of years . In fact the company is the result of successive consolidation of the Swiss watch industry. ETA manufactures quartz movements, hand wound movements and mechanical movements powered by self-winding mechanisms. Because ETA maintains vertical control over the manufacturing of all of the components required to create a watch movement (save for the hairsprings which are made by its sister company Nivarox) ETA may be considered a true manufacturer.

[edit]A Brief History

ETA SA Manufacture Horlogère Suisse is one of the world's largest manufacturers of watches and movements.^[1] In 1856 at Grenchen, Urs Schild, a schoolmaster, and Dr. Girard set up a watch movement (ébauche) factory which eventually became Eterna. In 1926, ETA AS (the movement branch of Eterna, founded in 1896) and FHF (founded in 1793) took part in the creation of Ebauches Ltd. In 1978 AS and ETA merged and in 1985 ETA took in all the activities done before by Ebauches Ltd and FHF (both part of SMH/Swatch Group).^[2]

In 1998, SMH Swiss Corporation for Microelectronics and Watchmaking Industries Ltd, founded in 1983 through the merger Swiss watchmakers ASUAG and SSIH, was renamed the Swatch Group.

At the time, both SSIH and ASUAG held a number of well-established Swiss watch brands. ASUAG had been founded in 1931. ASUAG expanded through the purchase of companies that made movement-blanks and a number of finished watch manufacturers that were subsequently brought together under the subsidiary GWC, General Watch Co

SSIH was founded in 1930 through the amalgamation of Omega and Tissot. By consolidating companies that produced high-quality movements and a number of watch brands, SSIH gradually established a strong position in the Swiss watch industry.

In the 1930s, both ASUAG and SSIH entered into complementary research and development programs to combat a severe economic crisis. Following repeated crises in the Swiss watch industry, by the 1970s both ASUAG and SSIH were again in trouble. Foreign competition and the mass production of cheap new electronic products were taking over the market. Eventually, both ASUAG and SSIH faced bankruptcy.

In 1983, critical steps including the merger of ASUAG and SSIH into SMH and the launching of a low-cost, high-tech, artistic and emotional “second watch” - the Swatch. Invented, developed and launched by Ernst Thomke and his team. ^[3]

During all those years of crisis, and restructuration, since 1978, Dr. Ernst Thomke had been at the helm of ETA SA, and also had become CEO of Ebauches SA and appointed on the Board of Directors of ASUAG. He became SMH's first CEO, position he held until 1991. At that time, Nicolas G. Hayek, as newly elected Chairman of the Board and main shareholder had already become the only person of reference.

[edit]Workhorse mechanical movements

In recent years there has been an increase in interest in mechanical watches. ETA supplies the overwhelming majority of mechanical watch movements found in Swiss watches. As such, the ETA movements are considered the workhorses on the industry. Moreover, ETA has come to control a virtual monopoly over the production and supply of watch movements, more on that issue below.

[edit]ETA 2824-2

One workhorse of the ETA mechanical line is the ETA 2824-2, The 2824 is an automatic winding, twenty-five (25) jewel movement, available in four executions or grades: Standard, Elaborated (improved), Top and Chronometer^[4]. The key components which differ at the line of demarcation between Elaborated and Top are the barrel spring, shock protection system, pallet stones, balance wheel & hairspring and the regulator mechanism. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications:

• the Standard grade is adjusted in two positions with an average rate of +/-12 seconds/day, with a maximum daily variation of +/-30 seconds/day;
• the Elaborated grade is adjusted in three positions with an average rate of +/-7 seconds/day, with a maximum daily variation of +/-30 seconds/day;
• while the Top grade is adjusted in five positions with an average rate of +/-4 seconds/day, with a maximum daily variation of +/-10 seconds/day.

The Chronometer grade must meet strict standards prescribed by the COSC. Chronometer grade movements are serial numbered as that is a requirement of the certification authority. Moreover, it should be noted that the degree of decoration on the movement's parts, generally only an aesthetic improvement, increases as well with the grade.^[5]

[edit]ETA 2892

The ETA 2892.A2^[6] is however, widely considered the more upscale of the basic ETA movements, and it certainly a newer design dating to the 1970s where as the 2824 traces its roots back to the 1950s. The 2892 is fitted with top quality components. The 2892 is an automatic winding, twenty-one (21) jewel movement, available in three executions or grades: Elaborated,Top and Chronometer. The key components which differ at the line of demarcation between Elaborated and Top are the pallet stones, balance wheel & hairspring, and the regulator mechanism. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications:

• the Elaborated grade is adjusted in four positions with an average rate of +/-5 seconds/day, with a maximum daily variation of +/-20 seconds/day;
• the Top grade is adjusted in five positions with an average rate of +/-4 seconds/day, with a maximum daily variation of +/-15 seconds/day.

The Chronometer grade must meet strict standards prescribed by the COSC: an average rate of -4/+6 with a maximum daily variation of +/-5 seconds/day. The wider range for the Chronometer grade is designed to take into account the differences in a watches rate between static positions, as when the tests are performed, and the dynamic positions as when a watch is actually worn. Chronometer grade movements are serial numbered. Moreover, the degree of decoration on the movement's parts, generally an aesthetic improvement, increases with the grade.^[7]

The 2892.A2 is regarded by many horologists as being in the same 'quality' range (accuracy and reliability) as the in-house produced Rolex movements.^{[citation needed]} Insofar as accuracy is concerned any movement which is expected to be COSC-certified, or is in fact COSC-certified, must meet the same standards. The ETA 2892.A2 is usually found in the more expensive and prestigious watches and brands. Owing to its relatively slim height of 3.60 mm, the 2892.A2 is a favorite of watch brands that market complicated movements such as Breitling with its trademark chronograph (stop watches). Given the slim dimensions of the 2892, it provides a good platform on which to add or build a chronograph complication. It is also used in IWC's Portofino line without complications simply for its small size.

[edit]The Omega Co-axial based upon an ETA movement

Omega's popular Seamaster line of watches currently use an embellished version of the ETA 2892.A2, which is known as the Omega 1120. As an adjunct, some versions of the Omega watches may be fitted with the proprietary Co-axial escapement invented by George Daniels, an English horologist and exclusively marketed by Omega a sister company of ETA. The movement with the co-axial escapement is known as the Omega 2500 series and is derived from the ETA 2892.

[edit]Valjoux 7750

The Valjoux 7750^[8] a/k/a ETA 7750 is a widely used chronograph (stop watch) movement operated by cams integrated into the movement. The traditional mechanism used in the chronograph is known as the Column Wheel. With the advent of the Valjoux 7750, the column wheel was abandoned for a three (3) plane cam system. The three plane cam system is properly known as the Coulisse Levier mechanism. The system and movement were developed by Edmond Capt in 1970, as a fully integrated self-winding mechanism with quick-set day/date based on the Valjoux 7733.^[9]

The movement is an automatic winding, twenty-five (25) jewel movement, which can be fitted with a variety of features including the triple date (day, date, month and moon phase) or a variety of two and three register models with totalizers or counters for minutes, seconds and hours. It is available in three executions or grades: Elaborated, Top and Chronometer. The key components which differ at the line of demarcation between Elaborated and Top are the pallet stones, balance wheel & hairspring and the regulator mechanism. To illustrate the differences in accuracy garnered by the successive grades, consider the following specifications: the Elaborated grade is adjusted in three positions with an average rate of +/-5 seconds/day with a maximum daily variation of +/-15 seconds/day; while the Top grade is adjusted in five positions with an average rate of +/-4 seconds/day with a maximum daily variation of +/-10 seconds/day. The Chronometer grade must meet strict standards prescribed by the [COSC]: an average rate of -4/+6 with a maximum daily variation of +/-5 seconds/day. ^[10]

[edit]Monopoly allegations and investigations

In the Swiss watch industry, there was a two-year investigation^[11] into certain aspects of the business practices of ETA SA. The investigation was concluded in November 2005 by the Swiss Competition Commission with the finding that ETA was abusing its dominant market position. ETA had had the intention to discontinue its supply of ébauches (movement blanks) as of January 2006 and thereafter to supply only fully assembled watch movements and its own brands (the so-called “phasing-out”).

ETA argued that it was overwhelmed with orders and that its ébauches were sometimes ending up in fake (a/k/a replica or trademark pirated watches). ^[12] ETA also warned that there could be another crisis in Swiss watch making unless there was more innovation and investment. Nicolas Hayek, then the CEO of Swatch, the parent of ETA observed,

"[t]ere was no innovation, no new development, and when I pushed them to start doing new production, everybody started shouting... I said I was not going to deliver any more of my movements unless they try to do their own production... Otherwise the Swiss watch industry will suffer exactly the same problems it had before and it will go down.

However, the investigations revealed that ETA held a dominant position in the market for Swiss made mechanical ébauches up to a unit price of CHF 300. The regulators determined that stopping deliveries to third parties would have threatened the future of many small watchmakers in Switzerland and the termination of supply was to be regarded as an unlawful refusal to do business and therefore as an abusive practice. For numerous competitors, the implementation of the phasing-out within such a short time meant in practical terms that they had been deprived of the basis for their business activity, as there was no alternative supplier.

In an amicable settlement, ETA committed to supply the ébauches until the end of 2008 at the current volume and thereafter for two additional years at a reduced volume. This will create a situation in which alternative production plants may be set up. The regulators said the agreement gives small watch making companies in Switzerland enough time to adapt to the market and find new producers. ^[13]

This has spurred on progress in the watch movement circles with several brands developing proprietary movements, for example Panerai. Another discrete movement maker, Progress Watch Corp. also came into the market for a period of time. ETA movements have also been duplicated by various enterprises including Asian manufacturers and are usually being produced without license^[14].