Re:Casio G-Shock time sync radio
by JCM9 on Wednesday August 16, 2023 @06:27PM
(#37154714)
GPS signals are much higher frequency and very low power and thus don’t work indoors. These HF time signals are way more powerful and can be detected inside buildings.
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In the interest of the previous reply, Casio's GBD-H1000 has the ability to time sync with GPS.
Re:Casio G-Shock time sync radio
by friend_and_foe on Thursday August 17, 2023 @01:03AM
(#37157461)
Yeah but it needs to be charged often. That would be a compelling use case for the radio based timing synchronization that are in less power hungry watches, and I'm curious, if this watch just had GPS for timing and none of the other features, if it's power would last as long or even half as long as the older models.
The H1000 is marketed as a fitness watch and solar powered too. The GPS time sync is not an exclusive feature and I find that it isn't necessary to have it on constantly.
> GPS signals are much higher frequency and very low power and thus don’t work indoors.
With a $20 antenna placed near the window, together with a modern receiver, it is easy to get nanosecond level of precision for GPS systems. Some receivers even have in-door precision specification.
GPS not only work indoors, in terms of timing, it works actually pretty well indoors.
Why would I need that for? nanosecond accuracy? GPS indoors?