The Timex Model 50 Series is very similar to the Model 40 Series, the main difference being the presence of a diode on the balance which makes them electronic movements rather than electric movements.
This series also has the Model 65, a dual time zone electronic movement and my example is shown below
- Model 50 : electronic : 21,600 bph : no date
- Model 51 : electronic : 21,600 bph : date
- Model 52 : electronic : 21,600 bph : day and date
- Model 65 : electronic : 21,600 bph : day, date and dual time zone