In the late 1960s, at the exact moment of the Speedmaster's greatest triumph, Omega swapped its heart. The caliber 861 replaced the column-wheel 321 with a cam-actuated design that was cheaper to produce and easier to service - quartz-crisis economics arriving a few years early - and the 145.022 carried it for roughly two decades, the longest run in the family. Sources split its introduction between 1968 and 1969, and the file marks it accordingly.
The reference's most famous variant is the gold BA 145.022: 1,014 pieces with a burgundy bezel, the first watches presented to astronauts at a Houston gala on November 25, 1969, with numbers reserved for the Apollo 1 crew and a sitting president. The steel version, made in enormous numbers, is the sane entry into vintage Speedmasters and the reference most collectors actually own.
The people's Speedmaster. Twenty years of production means variants to learn (step dials, applied logos, bezel generations) but also means enough honest watches that nobody needs a doubtful one. The trap here is the opposite direction: later 861 watches dressed up with 321-era parts to climb the price ladder. Date the movement, then judge the dress.
Production windows and specifications compiled from documented collector references and period catalogs, cross-checked across independent sources; manufacturer records for this era are approximate by Seiko's own account.