La Grande Classique de Longines
Lyre
ETA 255.511
Factory Spec. 10 SPY
Thermocompensated: Dual Oscillator (32 kHz + 262 kHz)
User Adjustable: Yes
There appears to be relatively little data available on the dual oscillator movement in this watch, however I have read that ETA used crystals with frequencies ranging from 262 kHz to 2 MHz as the auxiliary oscillators. Assuming that is true, then, given that this is a slim-line, dress watch with a small battery, I'd assume that the auxiliary oscillator in this case is of the 262 kHz persusion.
Some details of this watch are missing as it is not well documented and has yet to undergo comprehensive tests.
| Parent Company | Swatch Group |
| Brand | Longines |
| Model Series | La Grande Classique de Longines |
| Model Name | Lyre |
| Model Number | 173 |
| Case Number | 7176 |
| Serial Number | 25047570 |
| Approx. Date of Manufacture | from 1985 |
| Calibre (mvt maker) | 255.511 |
| Calibre (brand) | L 173.4 |
| Factory SPY | 10 |
| TC Appproach | Dual Oscillator & Count Adjustment |
| Frequency (XO 1) | 32 kHz |
| Frequency (XO 2) | 262 kHz |
| Rate Adjustment | User |
| Major Inhibition Period | unknown |
| Minor Inhibition Period | unknown |
| Power | Disposable Cell |
| Cell Number | SR916SW |
| Case Back | Press (requires case press for closing) |
| Water Resistance | Not stated |
| Features | 3-hand, no numeral dial |
| Date (not perpetual) | |
| Timing Results | Basic data & Further details |
| Images | Photos - Large File Sizes! |
| Documents | Technical details |