ATCA NASA Tracking Setup

General Information

CDSSC Ops Center: (02) 6201 7940 or (02) 6201 7942. We are DSS47.

Cassini is in Ka-band (7mm) 32030 MHz

Mars Odyssey is in X-band (3cm) 8407 MHz

Testtone Ka 32164 MHz

Initial Preparation

Schedule filename Target / Track ID

Target above 12° @ UTC (RISE)

Target below 12° @ UTC (SET)

BOT (from SOE) @ UTC (Beginning of Track according SOE)

EOT (from SOE) @ UTC (End of Track according SOE)

Frequency MHz + or – 4 MHz offset:

Calibrators

Track setup

NASA Tick phase µs ATCA Tick phase µs

Track Execution

Tid Operator name

On source @ UTC

Confirmed signal @ UTC Signal: dB

Track ended @ UTC

Where	þ	What
in screened room		The DTT 'LO CHAN' switch needs to be set for the appropriate side band: Up for EVEN Inversion (e.g. X band), Down for ODD Inversion (e.g. Ka band).
		Check and note the time tick phase for the NASA 1PPS and the ATCA 1PPS on the ATDC display next to the
xbones		Mission support files are copied by Tid to nelle:/home/jpldata If this has not been uploaded by Tid on the last working day BEFORE the track, contact Len Ricardo or CDSSC Ops on the phone number above. A local cron job copies this to xbones:/home/atcaobs/jpldata *.geo* files are geocentric position predicts. To convert these to caobs ephemeris files run ssh into xbones and execute “preformat”: xbones> preformat It will ask for a filename and an output name. The output name is the source name for sched, i.e. m01slj. In atcasched, this must then be referenced as @m01slj *.tsoe* files are a time sequence of events and useful to print out for information. *.dlf* contain frequency information. When creating the schedule, make sure you are using the proper frequency (1-Way / 3-Way) based on the SOE document. Check against UTC time. Remember to use a 4 MHz offset to either side to avoid birdies
atcasched Track Prep Track Prep Monitoring		Copy an earlier schedule and verify the source name is properly set to the one you've just set up with preformat (e.g. sched> source @cassini) For the NASA track scans, verify that scantype is JPL_7 correlator config is a noblanking config (e.g. NB_FULL_64_128_2p-1f) For 4MHz BW obsvervations, use NB_FULL_4_2048_2P-1F calcode is set to C Also make sure you have an astronomical calibrator source near the target. Use this link to obtain rise/set and position information for a given RA/Dec: http://www.parkes.atnf.csiro.au/observing/utilities/utilities.html Use this for spacecraft rise / set information as well as sanity checking (occultations, angles, az, el etc.) http://www.narrabri.atnf.csiro.au/operations/NASA/ Use this for monitoring http://www.narrabri.atnf.csiro.au/nasa-monitor/
Caobs		Start tracking the astronomical calibration source (usually caobs> track 2). When on source, ensure all antennas are attached (e.g. caobs> attach ca06 ). If antenna refuses to attach, try resetting the ACC: caobs> reset ca06
		When using selfcal while in JPL_7 (noblank) mode check that the phase numbers scrolling by on caobs converge to zero in a few cycles (in good weather) or at least look random around zero. If there is a fixed offset between X and Y of 90 or 270 degrees the phase updates are not working and a scan restart is required. Similarly in vis the phases should converge when selfcal is enabled and the tied array amplitude should improve and stabilize. CAOBS can get into the wrong state if some of the 'INTROT' messages to the antennas at the start of the scan are lost and the antennas never switch to noblank mode.
cacor		Ensure the proper version of cacor is running. If narrowband observations are required (i.e. BW 4MHz), pkchan must be supported. Issue cacorver current then start cacor. In the command window of cacor, enter gpib to connect to the gpib. Other cacor version include previous and dangerous.
		Execute the command gpib in the correlator. Ensure that the DTT has properly initialized. See correlator log. Check for “GPIB OFFLINE – No NASA DTT LO control”. If that message appears, caobs and cacor need to be restarted.
		If using 7mm receivers: set focus heights to 7mm focus position (e.g. caobs> focus ca01 16) To check the current focus position, see MONICA: Misc -> subreflector -> focus. (see Current Issues pages for correct position).
		If not in X-Band: Ensure that the samplers and C26 splitter modules are at appropriate levels. The caobs>chklev # command should set the mm attenuators so that the C26 power levels do not saturate. (where # is the scan number for a calibrator, at the required frequency and bandwidth) It also attempts to set the coarse attenuators, however, the coarse attenuator settings should be checked, as you can often do better manually - especially in poor weather. (See Current Issues pages for more Information.)
		If not in X-Band: check pointing
		set cycle time to 1.024 seconds: caobs> cain cycle 1.024
		calibrate the array (cacal on an astronomical source)
		in camon 4, ensure page 7 is visible (attenuators)
		set the reference antenna to none caobs> set ref none
		set up tied array mode. caobs> catie connect caobs> catie ant 123456 123456 Check or set: caobs> catie gain 2 2 2 2 caobs> catie function xx-yy xx+yy xx-yy xx+yy
		To display amplitude of the vector averaged signal, use s in vis: vis> aps-t
		Start observing: use a caobs> start command (not caobs> track) Using start does set up noblanking mode. track does NOT do that!
		Disregard if in X-Band: Check that the test tone is working (caobs> set tton and caobs> set ttoff and check for the tone on CA05 in spd)
		When on the spacecraft. Zoom in to find the channels that the signal is in. Execute spd> a (amplitude plot) and then spd>x to set the x axis to channel (not frequency) close in on the carrier with spd> chan x1,x2 set the system to use these channels with: cacor> sigch x1 x2 [x3 x4] if using 4 MHz bandwidth, use this to automatically track cacor> pkchan x1 x2 where x1 and x2 define the start and stop channels for frequency 1 (e.g. the spacecraft signal when doing NASA tracking), x3 and x4are for frequency 2. If tied array amplitudes are fluctuating: Setup the baseline channels as well (usually necessary when in compact configurations, when the signal from the planet can be significant) cacor> bg1ch x1 x2 [x3 x4] sets the background range for the low numbered channels and cacor> bg2ch x1 x2 [x3 x4] sets the background range for the high numbered channels By default, the DTT looks for its own BG channels, they only need to be set manually if another strong signal is nearby (such as MRO or MEX when tracking M01).
		start selfcal caculation in caobs: caobs> selfcal on
Selfcal information		Selfcal calculates the phase change with respect to a reference antenna and applies this offset to the data. The reference antenna is the reference antenna from immediatly before the caobs> set ref none command If there are long baselines, an antenna in the middle of the array should be choosen. If there are problematic antennas, they should be avoided.
		verify the cycle time is 1.024 seconds: caobs> cain cycle 1.024
Things to check		When using JPL_7 mode, the IF levels for the JPL signal should be displayed in the cacor log window. DTTIF Freq 1642.000 MHz Power 9.0dBm There should be a red error message if there are problems with this
		Always check for the "Stop/start" problem. Usually if you get the first cycle ok, there shouldn't be any problems. However, sometimes you need several caobs> stop followed by caobs> start commands before the signal is good.
		The web monitor page is at: www.narrabri.atnf.csiro.au/nasa-monitor/
During the track		Establish contact with the CDSCC Ops Centre and note down the signal strength received on their end.
		If an antenna stops tracking, it can be reattached to the array with: caobs> restart ca0#
		If an antenna loses sync, it can be resynced to the array with: caobs> resync ca0#. At present this will also resync the associated antenna in the delay rack (i.e. caobs> resync ca02 will resync CA02 and CA05).
		If an antenna can't be reattached to the array, it should be removed from the tied array calculations. Use the catie ant command for that.
At the end of a track		Please log any information and keep it in the NASA Tracks folder. Even if everything went well, please note so and add any supporting evidence.
		stop the automatic calibration: caobs> selfcal off
		return to using the 'normal' channels in the correlator: cacor> tvchan default
		set cycle time back to normal: caobs>cain cycle default
		set reference back to normal antenna: caobs>set ref ca02
		stop catie caobs> catie close
		if appropriate, return to original focus heights
		close the correlator file caobs> corr closef

Notes

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Notes

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