Editorial
The Polaris Memovox Q903847J is Jaeger-LeCoultre's reissue of the dive-alarm that made the Memovox name matter: 200 metres of water resistance paired with a mechanical alarm that rings at a preset time using a spinning disc rather than a striking train. The calibre 956 delivers both functions in a package collectors value for its rarity among complications, since a true mechanical alarm is a fundamentally different animal from a minute repeater or a chime. At 42mm in steel it wears large but not absurd, and the navy-dialled aesthetic tracks closely enough to the 1968 original that it reads as a coherent re-edition rather than a marketing exercise.
JLC introduced the modern Polaris Memovox as part of the Polaris line revival that began in 2018, reinterpreting a reference with roots in the 1959 Memovox Automatic and the 1968 Polaris dive-alarm. The Q903847J runs the calibre 956, a self-winding movement with a separately wound alarm spring and a rotating disc mechanism that produces the alarm sound when a hammer strikes the case at the set time. The 956 is a direct descendant of calibre 916 movements that established JLC's alarm reputation decades earlier.
JLC has offered the Polaris collection in several configurations since 2018 including a three-hand date variant and a world-time version; the Memovox sits at the top of the range within the steel Polaris family. Production is ongoing as of 2025, and no limited-edition caveats apply to the standard Q903847J.
Verify the alarm function works correctly at purchase: set it, let it ring, and confirm the tone is strong and consistent, since a weak or absent alarm can indicate a depleted alarm mainspring or a worn disc hammer. The 956 has two separate crowns, one for hands and one for the alarm; check that both operate with positive detents and no slop, as worn crown stems are a known wear point on alarm-complication movements. Inspect the case for crown-tube damage, particularly around the alarm crown at 4 o'clock, which sits in a vulnerable position on the case flank.
Water resistance should be confirmed with a pressure test before any aquatic use, especially on pre-owned examples where gasket service history is unknown. Confirm the reference number matches the specific configuration you want: the Q903847J is the navy-dial steel version and other Polaris Memovox variants carry different Q-numbers.
