| Brand: | Miyota | 
|
|---|---|---|
| Family: | ||
| Height: | 5.94 mm | |
| Jewels: | 21 | |
| Reserve: | 42 hours | |
| Frequency: | 21600 A/h | |
| Winding: | Automatic, Counter-Clockwise Automatic Winding | |
| Diameter: | 29.20 mm (13 ligne) | |
| Complications: | Date, Day, Hand Winding, Outer Day Wheel, Quick Date Correction | |
| Hands: | Central Hour Hand, Central Minute Hand, Central Seconds Hand, Date Window at 3:00, Day Window at 12:00 | |
| Production: – | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1910s | 1920s | 1930s | 1940s | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
Part of the Miyota Cal. 8200 family, Cal. 8285 is a day-date central seconds automatic movement. Unlike the day-date Miyota 8205, Cal. 8285 features an outer day wheel, showing the day of the week in full at 12:00 instead of an abbreviation at 3:00. It is mono-lingual.
All members of the Miyota 8200 family have indirect seconds, which causes a noticeable wobble to the central seconds hand. When struck, the seconds hand can appear to pause for up to 2 seconds due to slack in the movement.
| Hand Winding | Automatic | Automatic 24 Hour Hand at 9:00 | |
| Central Seconds | 8270 8270A 8260 (Date) 8260A (Date) | 8200 (Day-Date) 8200A (Day-Date) 8203A (Day-Date) 8205 (Day-Date) 8205A (Day-Date) 820A (Day-Date) 8210 (Date) 8210A (Date) 8215 (Date) 8215A (Date) 821A (Date) 8228A (Open) 8285 (Day-Date) 82S0 (Open) 8N24 (Skeleton) 8N26 (Skeleton) | 8217 (Date) |
| Small Seconds at 4:30 | 8218 (Date) 82S5 (Open) 8N40 (Skeleton) | 8219 (Date) 82D7 (Open) 82S7 (Open) |