Don’t GPS Systems Work All Over The World?

GPS signals can be received all over the world, provided that you have a clear view of the sky to acquire the signals from at least four satellites. Assuming you have locked on to at least four satellites,  a GPS-based collar must then send that data, either by radio frequency signals or by cellular telephone, back to the pet owner. GPS systems that use cellular service generally do not operate outside the US. So no, GPS based pet tracking collars don’t necessarily work all over the world.
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