[time-nuts] USB Low Cost GPS Timing Receiver

[Hal Murray]

brooke at pacific.net said:
> A friend is looking for a low cost GPS receiver to set the clock in the
> computer that controls his telescope mount.  USB would be nice but is not a
> requirement. 

What sort of accuracy does your friend need?

> For example does eBay item 130456356506 set the computer clock?

eBay says "SiRF Star III".

That's a very common modern GPS chip set.  It speaks NMEA.  On USB, it shows 
up as a Prolific PL2303 chip.  Most Linux distributions include a driver for 
it.  I assume Windows does the same.

It won't set the PC clock all by itself, but there is lots of software smart 
enough to process NMEA.

They suck for timekeeping.  (Especially if you are a nut.)
  http://www.megapathdsl.net/~hmurray/ntp/GPSSiRF-off.gif
If you are happy with close to a second, they are good enough.  You can 
probably get to within 200ms.


I've tried a couple of the thumb-drive size/shape USB packages.  They don't 
work as well as the "mouse" with a cord (tail?).  I'm guessing the antenna 
works slightly better if you have a bit more room to work in.


-- 
These are my opinions, not necessarily my employer's.  I hate spam.