Time.apple.com sync

Other Ham operators have complained that waking a Mac from sleep takes an unknown amount of time to sync the clock with NTP and you can be off by several seconds until the time is actually updated. It used to be trivial to kick the timed process into gear and force an update but not anymore. Due to security changes in macOS you can't force timed to sync.

There is an alternative cross-platform open source solution with much greater control: chrony.tuxfamily.org

However, that requires compiling the daemon and configuring by hand.

Fortunately, there is a GUI solution called ChronyControl specifically for macOS that will install the chrony daemon and let you control it far more easily.

https://www.whatroute.net/chronycontrol.html

It's not the speed of Wi-Fi that's a factor nor Internet connect speed and bandwidth. The NTP protocol is super lightweight and efficient.

The problem is with the fact that the 'timed' daemon is not sync'ing the time immediately upon wake from sleep. There is little rhyme nor reason to when it updates. It will eventually update but the scenario is you wake the Mac from sleep and now your clock is off by seconds or milliseconds which completely messes with Ham operators when using a Mac to decode a stream of data. Ham operators need extremely precise clock time.

ChronyControl and it's included Chrony daemon will disable the built-in NTP 'timed' daemon from being able to update the system clock. Then it takes over the function and updates the clock in a more aggressive fashion. ChronyControl is frequently mentioned by Ham operators on their forums as solving the problem on macOS for them.

I use time.nist.gov

I guess I should add, my Wi-Fi is approx 400 Mb/s up and down.

James Brickley wrote:

IThe problem is with the fact that the 'timed' daemon is not sync'ing the time immediately upon wake from sleep.

I wouldn't know. I never put my Macs to sleep.

JacquesZS1WC wrote:

I have tried that server. Still the same.

Just curious, does the problem only occur right after coming out of Sleep as James suggested?

Seems you rebooted thus allowing the Chrony daemon to start. You may also have seen a Login Items notification about allowing it as a background login item.

Interesting. And none of my 7 Macs are ever behind. Glad Jame's suggestion worked for you.

NTP is sensitive to network latency.

Try one of the local NTP Stratum 2 time servers: http://www.time.org.za/

Another pool: https://www.pool.ntp.org/zone/za