Good point - are there any low cost or at least widely available integrated IC receivers? There's the MAS6180C but that doesn't seem to be commonly available at

Good point - are there any low cost or at least widely available integrated IC receivers? There's the MAS6180C but that doesn't seem to be commonly available at any of the big distributors. GPS works, but then your clock needs to be near a window and needs some way of being updated for local tzinfo changes.