Thread: Garmin Timezone Map v8 (compiled April 13, 2011)

how does this differ from the default that is avail to all garmins. I thought the map auto changed times depending on what it receives from the satellites

Originally Posted by max_clif

how does this differ from the default that is avail to all garmins. I thought the map auto changed times depending on what it receives from the satellites

Yes., Nuvi adjust time from the satellites by correctly "Time zone"(GMT) in device.
"Time zone"(GMT) in device is set by co-ordinate you are( + with gmaptz ).
what exactly GMT when we stand around country border ?
Newer version may clarify about it ????
Just my idea.

Has anyone installed this in a nuvi 1300
Does it work ?
Is it safe to install ?

Originally Posted by max_clif

how does this differ from the default that is avail to all garmins. I thought the map auto changed times depending on what it receives from the satellites

GPS satellites transmits GPS time (week & seconds) and the UTC time (Coordinated Universal Time) to the GPS receiver. Local time is displayed either by manual setting of the timezone or automatically by using "gmaptz.img" to fetch the local timezone at your current position. Using "gmaptz.img" automatically is very practical if one travels east<->west and crossing time zone(s).

NMEA 0138 - GPS Fix Data Sentence (PGRMF):


Time zones present (from March 27, 2011):

Code:

Please Login or Register to see the links

The UTC time is very close to GMT but may differ in sub-seconds level and it also uses leap seconds.

Extract from Wikipedia:

As the Earth's rotation continues to slow, positive leap seconds will be required more frequently. The long-term rate of change of LOD is approximately +1.7 ms per century. At the end of the 21st century LOD will be roughly 86,400.004 s, requiring leap seconds every 250 days. Over several centuries, the frequency of leap seconds will become problematic.
...
...

Originally Posted by rob63

Interestingly, the file is not yet available via Webupdater (at least not for my Oregon..).

Many system files become available via Webupdater with several delay. So there are new version of file in retail device. It is mystery of Garmin.
Timezone Map v8 is just at time. Garmin compile this file twice of year - november and april. It is time for switch to summer and winter time?!

The file was delivered together with a map update, also not by web updater.
Should be available soon

What directory must it be saved into?