Clocks should either use the grid's AC signal or receive time codes from WWVB or other sources such as cell phone towers or broadcast TV. You can't get any more accurate than that even if you have a crystal --it should at least be counting mains power cycles, as the utilities synch to NIST. I have two WWVB clocks that automatically track time.
"The current version of NIST-F1-if it were operated continuously-would neither gain nor lose a second in about 70 million years. The latest version of the mercury clock would neither gain nor lose a second in about 400 million years." http://www.nist.gov/pml/div688/grp40/wwvb.cfm Hoyt Stearns Scottsdale, Arizona US -----Original Message----- From: Jed Rothwell [mailto:jedrothw...@gmail.com] Sent: Wednesday, March 30, 2011 2:28 PM To: vortex-l@eskimo.com Subject: Re: [Vo]:Another problem with electricity in Japan, the AC frequency varies mix...@bigpond.com wrote: > I wasn't talking about clocks with synchronous motors, but rather electronic > clocks that use the line frequency directly&/or for synchronization, and I > think there are still quite a few of those. I know what you mean. I used to have one. I think it burned up one day. I do not recall seeing any for sale in stores for 30 years or so . . . There are some web sites about this, in which line frequency electric clocks are referred to as "antiques." Wall clocks these days use AA batteries, don't they? - Jed
