This page contains notes on how to replace a failed TCS Alphastation. They will be of interest mainly to Duty Engineers.
LPAS3 is the development TCS Alphastation and lives in the WHT
computer room, behind the time service. It also serves as a backup
machine for any of the Alphas used for TCS control. It contains copies
of the current operational TCS versions for all three telescopes. In
theory you just unplug the dead Alpha, plug in LPAS3 and you're
away. In practice the swap needs a little care.
Currently, the WHT and INT telescope Alphas are running VMS 7.3-2, the JKT is running VMS 7.1. The system disks of all Alphas are shadowed. LPAS3 can run either VMS 7.1 or VMS 7.3-2 depending on which disk it was booted from. Separate instructions are provided for each telescope, as some details are different.
Instructions for JKT :-: INT :-: WHT
A photograph of lpas3 in its normal resting place, the WHT computer room.
