Checking the Accuracy of the Clock on a NuTone IM4006 - Sends me down a Rabbit Hole of Thoughts 

Hi Brennan: You're welcome - I honestly don't think the Clock should be this inaccurate - Look for more about this in the near future - Chris

Hi jbs487: Good to know - I'm not done with this topic - look for more about this in the near future - Chris

Hi Kurt: Depending on how fast or slow your clock runs - it may be "typical" or it may be related to the Master Station needing ot be rebuilt - Chris

Hi r.rasmussen: I think most of the clocks are failry accurate - not really a problem for most - I guess I did a good enough job on this customers Im4004, becuase he never called about the clock again - Chris

Hi zx8401ztv: You're right on with your suggestions - I'm not done with this topic yet - Look for more in the near future - Chris

Hi rkuns: This what I found about your idea; "No. The iPhone is, at best, a Stratum-2 level clock. That is because, according to Apple, the iPhone (and Apple Watch) get their time from Stratum-1 clocks. This means they’re one step down from S-1, so they are S-2 devices. An actual atomic clock would be a reference origin device, or a Stratum-0 time source. So the atomic clocks are S-0, and the iDevices are [again, at best] S-2. That doesn’t mean they aren’t “perfect for all aspects of human consumption.” The difference between strata isn’t that great. For a Stratum-2 device, as long as it is synced at least once every hour, then it will remain accurate to within 46 microsecond. Even if you, somehow, managed to keep the phone battery charged but the phone completely disconnected from cell/wifi/bluetooth/gps - it would still take 91 days before you lost 1 second of time. And if the iPhone ever reconnects to the internet, then it will re-sync the clock to within 4.6 microseconds of the origin reference (the atomic [S-0] clock that feeds the S-1 clock that the phone is syncing to). So can we say it is “as accurate as an atomic clock” - no. But only because when you make that kind of statement you are talking about accuracies which are physically beyond the capabilities of the electronics in the iPhone. Can we say “the iPhone is more accurate than any human’s ability to discern time?” Yes, we’re pretty safe in that statement; just make sure you connect to the internet at least once a month. (Russell Rocket ~ Studied Aerospace and Aeronautical Engineering at Texas A&M University (TAMU)3y) (no date shown) - Chris

@@northsideservicecompany3567 Plenty accurate to test multi day accumulated errors! The iPhone will keep getting back to correct time as the unity under test drifts away. Anyway, I’m an old ham radio operator, I set my watch to WWV by ear and hand.

I agree - the app is certainly much, much more accurate than is any clock that would be set by it - Chris@@rkuns

Hi TheCleric: Excellent point - Chris