This is the main window of Atomic Clock Service where you can see the activity log lines as well as the Synchronization state 

The Options window allows you to set a Synchronization period and a Time Offset. You may also set a maximum attempts number per a time server here 

This is the Time Servers window where you can see a list of worldwide Time Servers. Here you can add, delete or restore servers, while being able to see the Current server to which you are connected