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Re: Consistent error question
From: Bill B
Date: 2014 Oct 02, 17:42 -0400
From: Bill B
Date: 2014 Oct 02, 17:42 -0400
On 10/2/2014 3:51 PM, Greg Rudzinski wrote: > If you don't have a short wave then use GPS time or the attached online > link to UTC. I would not suggest taking time off a GPS unit for testing/calibration purposes. There has been discussion on this subject in the past. I have seen my Garmin's display skip over an entire second. (I actually made a video recording of that at 30 frames per second to be certain and time in seconds is not close to exact.) A Garmin engineer's explanation was that the GPS unit is relegating its processing power to read the satellites and process position, velocity etc., and the time display gets the short end of the stick. (Akin to an idiot cousin seated in a corner at family gatherings :-) You can pick up a decent atomic (radio controlled) wristwatch for use in the US of A for about $30 and change on Amazon. It can display the last time it reset itself automatically. Turn off the automatic feature and rate it for 10 days. (Mine runs 1 second fast over 8 days now if it does not auto reset.) If it fails to auto reset for some reason now and again when returned to automatic mode, you know it's rate of change and can adjust for watch error.
