[time-nuts] Spacecraft Timekeeping

[Magnus Danielson]

On 03/09/2011 06:08 AM, Kevin Watson wrote:
> Hi All. Thanks for responding. There are quite a few GPS receivers that
> will work outside of the usual commercial-grade GPS limitations, but I'm
> not too sure I need such a receiver. As my application is to just
> accuratly time-tag messages for a data recorder, my thinking is to allow
> a ruggedized GPSDO to stabilize on the pad before launch, and then just
> before launch force the GPSDO into holdover mode and act as the PTP
> grandmaster for the onboard computers until we reach orbit. Once on
> orbit I have other means to synchronize the PTP grandmaster.

Why carry the dead weight of something unusable in orbit.

Drop the receiver and antenna out of the equation and just provide a 
timing signal on launch pad...

Cheers,
Magnus