Cal. 230 was the first alarm movement from Venus, offering several novel features:
- An aperture in the dial showed whether the alarm was engaged or not
- The alarm and time-keeping functions run from the same barrel, unlike most other alarm movements
- A second crown at 4:00 must be pulled to enable the alarm, rather than pulled to silence it as on the Jaeger-LeCoultre Memovox
Cal. 230 lasted in production from 1954 through 1966. About 1,000 larger 12 ligne Cal. 231 movements were produced between 1956 and 1958. A third variant, Cal. 232, added a date display and parking meter function and was produced from 1959 through 1966.