Setting the time

Hal Murray hmurray at
Mon Aug 27 14:28:36 EDT 2012

> In a school deployment, it is desirable that all of the XOs have the  same
> time. This time should be synchronized with/by the school server  (even if
> the school server is wrong). It is not reasonable to base this  capability
> on access to the internet.

How closely do you need them to be synchronized?  1 second?  1 microsecond?  
1 minute?

It should be reasonably easy to setup ntpd on the school server and get the 
XOs to set their clocks when booted.

You may want/need a cron job to set the time occasionally.

> Casio sells 'atomic' watches that synchronize to Ft. Collins by radio.
> Neat, but how does this work in Rwanda? 

WWVB runs at 60 KHz.  There are several similar systems in other countries.  
I don't think any of them make it to Africa.  GPS does.

You can get USB GPS receivers for under $50.  The SiRF chip is the most 
popular in the low cost units.  It's crappy if you need ms level timing, but 
good enough if all you need is 1 second.

These are my opinions.  I hate spam.

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