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Re: WWV Broadcast Outages


From: Hal Murray <hgm+nanog () ip-64-139-1-69 sjc megapath net>
Date: Wed, 22 Feb 2017 04:59:53 -0800

"Majdi S. Abbas" <msa () latt net> said:
      That said, I and many others "still use" WWV -- there aren't exactly a
surplus of suitable backup methods to GPS these days. 

Any suggestions for gear and/or software that works with WWV (or CHU)?  Or general suggestions for non GPS sources of 
time?

Dave Mills had a driver in ntpd that used a PC audio port to listen to WWV.  
I don't know anybody who ever used it.  I think there was code to tell some 
brand of receiver with a serial/USB port how to change frequencies so you 
could use the one that worked best for that time of day.

There used to be WWVB (60 KHz) receivers.  The good ones phase locked to the carrier.  The general rise in EMI made 
those close to useless in most locations.  NIST finished the job when they changed the modulation format a few years 
ago.  As far as I know, there aren't any replacements for the old gear that take advantage of the new modulation 
format.  GPS works too well.

There are some boxes that recover the time from nearby cell phone towers.  I 
think they will stop working as the towers get upgraded to the newer 
protocols that use a different form of timing.  That will probably take many 
years.  But the cell phone towers depend on GPS.  (You can ususlly spot the 
conical antenna(s) if you look around a bit.)



-- 
These are my opinions.  I hate spam.




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