Changes
SHOC
,/* GPS Issues */
===GPS Issues===
* '''The GPS time is not valid:''' If the GPS reports that the timing is not valid, check that it is able to see at least a few satellites, and that the signal quality is acceptable. Click on the Receiver Status button on the GPS tab, and a pop-up should appear, displaying the signal quality of the visible satellites. If each signal quality bar is zero, check that the dome is open; the antenna can't detect the satellites if it's closed. If there are a number of satellites visible, each with a reasonable signal, you might need to wait for a while for the GPS to rgister this and for the time to become valid. Normally this happens quite quickly, but for reasons we don't entirely understand, sometimes this can take five or ten minutes.
It may also help to put the GPS into dynamic mode. Usually the GPS is set to operate in static mode, where the known position of the telescope is used. In dynamic mode, the GPS will first locate itself before getting a lock on the time. It may be that doing this will help to get a lock on the time.
To put the GPS into dynamic mode, or to return it to static mode, use the command line interface described below. (One can also return the GPS to static mode by doing a "restart_services" call.
To use the command line interface:
** Fire up a terminal
** ssh <user>@<shocndisbelief|shocnawe>.saao.ac.za
** shoc-gps-cli
** The commands in the cli are help, status, pop, mask, bias, timing_mode and location.
** The timing_mode option makes the GPS use static or dynamic mode.
** The status option prints out all the current status reported by the GPS. If the command line tool reports an error while updating the status, simply try again until it works.
=== Rescuing Data===
