Monroe Electronics 639 - Manual (Page 13)

Or use ‘Set from Computer Clock’ as indicated here:
The third choice is only available if your network has a Network Time Protocol
server available, as shown below :
If you select ‘Set Time from NTP’, the time will be automatically set immedi-
ately. Also, the function of ‘auto update time from NTP at midnight’ is the
default setting. If you wish to disable this function, click on ‘Disable auto
update time from NTP at midnight’. The advantage of using it with a network
time function (NTP) is the constant synchronization of the clock in the 639. If
the DNS function is not familiar to you, consult your IT department.
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