Q: How often does the SPC373 sync with the atomic clock?
A: It attempts syncing at 12:00 AM, 1:00 AM, 2:00 AM, and 3:00 AM. It will also retry if the signal is weak.
Q: Can I disable the atomic sync and use only manual mode?
A: Yes. Set the clock manually, and it will not overwrite until you force a WWVB search.
Q: Does the clock work internationally?
A: The WWVB signal is only for North America (USA and parts of Canada). Outside this range, use manual mode.
Q: Why is my humidity reading higher than my other hygrometer?
A: The sensor takes time to stabilize after battery change (24 hours). Also, ensure the clock is not near a humidifier or bathroom.
Q: The snooze is too short. Can I change it?
A: No. The SPC373 snooze is fixed at 5 minutes.
Step-by-step:
Important: Do not press any buttons for the first 10 minutes after inserting batteries. The clock needs this time to lock onto the WWVB signal without interference.
The manual emphasizes a specific order of operations to avoid sync failures:
Reviewer’s note: Many users miss the manual’s advice to place the clock away from metal, concrete walls, or electronic devices (Wi-Fi routers, TVs). Doing so dramatically improves sync success.