> In our part of the world (NZ & Australia I think) there is a system
> using a "zach (?) pager" that receives time signals on the paging
> network

Pagemart, now WebLinkWireless, employed a "ReFLEX 25" network
that was HIGHLY dependent on GPS for synchronization throughout
the system -

both in time - for the transmitted data packets (all packets were
               time stamped as to WHEN to be delivered since the
               transmit sites operated in a 'simulcast' fashion)

and in phase - the radio 'sites'/towers in an area of the system
               transmitted in a 'simulcast' fashion the same
               'messages' or what are more correctly known as
               "R25 data frames" thereby requiring phase lock
               to a common standard.

So, knowing the protocol a ReFLEX 25 system (anyway!) could be
used for synchronization/time keeping.

RF Jim



----- Original Message -----
From: "Richard Prosser" <Richard.Prosser@ENERGY.INVENSYS.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, December 17, 2002 1:16 PM
Subject: Re: [PIC]: How to obtain the official US time clock?


> In our part of the world (NZ & Australia I think) there is a system using
a
> "zach (?) pager" that receives time signals on the paging network to
> control clocks, sprinklers etc. You may be able to use this (they claim
> accuracy is traceable to atomic standards).
> I've been meaning to try & identify the signals & see if I can use it but
> so far haven't had time.
> The systems sends out two signals per hour - the first is a "time mark"
and
> the second contains the actual time that the "time mark" was actually
sent.
> This gets around the delay between sending a paging signal to the network
&
> its actual transmission.
>
> May be of interest but I expect that GPS may be a better way to go
>
> Richard P
>
>
>

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