Today's watch is an example of the quartz dial version of a watch line I've only blogged an LCD watch from before.
In the early 1970s, Citizen Watch Co. released a line of quartz watches under the Crystron name. I guess that the name came from them containing a quartz Crystal and being elecTronic.
The watches came in a range of designs with several different movements being used in the range. This one is a 3 hand dial design with both a day and a date marker at the 3 o'clock position. It has a white dial with markers and not numbers, and has the Citizen CQ symbol on the bottom of the dial.
Based on the number on the front, it suggests a model 7100 module, although on the module itself it has 7300C, 280-18, and TW02. From these the 7100 and 7300C fit the Citizen numbering convention, but I can't be sure which (although my guess would be 7300). The serial number would indicate a 1979 date, but it may possibly be 1969. The model number is either 7100-711685 or 4-730771 with the old Citizens having numbers in both styles.
