JLC 497

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The JLC 497 is an automatic movement from Jaeger-LeCoultre.

Cal. 497 and 827

Calibre 497 debuted with the Jaeger-LeCoultre Futurematic Ref. E 501 and was much more advanced than the earlier Cal. 476/Cal. 481. It features a larger balance for improved accuracy and hacking seconds. One unique feature is a lock that holds the swinging weight in place when the mainspring is fully wound. It also features a special 6 hour power reserve, allowing the watch to immediately function when it is put on, rather than requiring it to be wound first.

The Calibre 497 featured a power reserve indicator along with small seconds located at the unusual position of 3:00.

Approximately 52,500 examples of Calibre 497 were produced between 1951 and 1958. Calibre 827 was quite similar, incorporating some changes from Cal. 817/837, and about 1,000 examples were made.

Calibres 817 and 837

Calibre 817 was used in the Futurematic Ref. E 502 from 1956 and was a modification of the existing Calibre 497. Like that movement, it has a power reserve indicator at 9:00 and small seconds 3:00, but in Cal. 817 and Cal. 837 these are tiny round windows rather than being full subdials. The power reserve uses a paddle-shaped indicator attached to the catch for the bumper rotor. It was a much-simpler display, half white and half red on Cal. 817 and black and white on Cal. 837. And the seconds disc has a simple arrow and no other markings.

Calibres 817 and 837 were produced from 1956 through 1958, with about 3,000 of Cal. 817 and just 500 of Cal. 837 made.

External links

Manufacturer:

Jaeger-LeCoultre

Description:

Bumper automatic movement

Functions:

Hour, minute hands
Small seconds at 3:00
Power reserve indicator dial at 9:00

Data:

13 3/4 ligne (31.3 mm)
Height: 6.3 mm
Balance: 2-spoke Glucydur with adjustment screws
Balance Spring: Nivarox spiral
KIF shock absorbers
17 jewels
18,000 A/h
Power reserve: 40 hours

Production period:

Predecessor: JLC 481
Production: 1951-1958