Data taking system checklist:
                                                               DSN   GBT
Login as user pfs

Verify net connection to other data-taking systems 
(rarg-pfs1, rarg-pfs2, rarg-pfs3, nrao-pfs1, nrao-pfs2)

Verify that computer clock is on UTC timezone
%date

Verify that NTP daemon is running and clock is locked
to time server
%ntpq -p

Verify that there is enough disk space on SCSI drive 
%df -k

Verify the path to executables (should be /home/pfs/bin) 
%which pfs_radar

Dial in desired sampling clock (5 MHz) 

Verify that sampling clock is locked to a standard 
(use a scope with clock in x and reference in y)

Verify that sampling clock and station tick are properly 
connected to PFS and are working (%pfs_trigger)

Connect low-pass filters to PFS data inputs 

Connect I and Q of Opposite Sense circular polarization (LCP) 
to rightmost PFS data inputs

Connect I and Q of Same     Sense circular polarization (RCP) 
to  leftmost PFS data inputs

Verify that we are getting receiver noise
%pfs_sample -m 5, should see changes in all channels

Adjust attenuation so that levels are approximately 0.25 Vrms:
-take data
%pfs_radar -m 5 -dir . 
-turn attenuator knobs while watching levels on end of file 
%pfs_stats -m 5 -e data??????????????.000

Take data histogram as a double check 
%pfs_hist -m 5 -e data??????????????.000
The data histogram should show all levels populated with 
a Gaussian or uniform distribution.
The highest levels should be populated 10% of the time 
at the very least.

When levels are set, take one minute of test data 
%pfs_radar -dir . -secs 60 -m 5
Verify proper operation by watching: start time, file size, stats.
Verify that bandpass looks normal by taking power spectrum

Turn on noise diode and record increase in level.