you are experiencing a common problem! You need a much higher SNR (signal noise ratio) for a moving object than for a not moving object.
If you start your engine in an underground parking lot, the gps receiver starts searching for valid gps just when you are out of the underground. typicaly it should have signal after 45 seconds but as you are moving the gps receiver is not able to get a valid signal of 3 or more gps satelites.
but 30-60 minutes is more than it should.
- check if you use external gps antenna (http://www.atrack.com.tw/products/ak1/ seems to have it).
- check if device does not fall into deep sleep mode (gps receiver switched off). it will delete internal almanac of sattelites. gps receiver should be always powered on!
- check if power of gps tracker is ALWAYS ON (and not switched off when you switch off ignition)
- check if gps antenna is on a location where it has CLEAR view to the sky
- check if you have NO metal on windows!
if i would be you, i would change location of gps tracker to the back of the car and put the antenna below the upper part of the back bumper!
(in general never heard about any serios problems with atrack HW, i am sure that it is a problem of wrong location of gps antenna and/or wrong deep sleep mode / missing power)
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