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observing:kband

K-band Astrometry (Ho-Hh)

Over the last few years, a series of experiments has been carried out make geodetic measurements at K-band. The results have been encouraging, and were included as part of the ICRF3 formulation. The observations have typically been carried out using the DBBCHO and mk5ho, although the recent failure of the mark5 has forced us to include the fila10G and flexbuff instead.

Setting up

  • terminate the FS running on hobart (with terminate) and restart it with fs-mk5ho-2gbps to load in the correct settings.
  • The experiment schedules are distributed as VEX files via email. Late updates can occur, so please check your email before starting an experiment if you have set up earlier.
  • When drudging the VEX file, you can accept the default settings for the backend and just generate the proc, snp and snap summary files (options 12, 3 and 5) before exiting.
  • Copy the snp and proc files to their usual locations and then edit the proc file to match ks1805ho.prc - this includes a number of additional or modified procedures to support the Fila10G/Flexbuff.
  • On DBBCHO, make sure that the DBBC Control software v105E_2 is running. If not, close the v104 software and v105_2 and let it configure.
  • From the FS, run “dbbc=pps_sync” and check that the clkoff and maserdelay results are similar.
  • As oper@hobart, run ./configure_fila10g.ks1804.sh
  • Load the procedure in the FS and run sched_initi and setup01. If the K-band (22 GHz) receiver is not on axis (rxp = 55 , 140, 5), then first send the telescope to service with source=service. Once it has arrived, please run rxselect in the operator input. This will ensure that the receiver can move to the correct location as moving in the Z-axis is unreliable with the telescope in stow.
  • Make a test recording with disk_record=on, disk_record=off and scan_check and confirm that the result is sensible.
  • Check iread and bread results. If the power levels are very low, there may be an issue with the receiver selection, Agilent frequency or the remote backend. If so, please re-run rxselect and sched_initi.
  • No formal start message to the IVS is required, but an email to Alet and Jon at Hart would be appreciated.

Monitoring

Please follow the usual checklist, with the following exceptions.

  • There will no no autocorrelation spectra
  • mk5=mode? will return mode? 0 : ext : 0xffffffff : 1 : 32
  • mk5=dot? will not return any information, and trigger an error.
  • disk_pos will not return any information, and trigger an error.
  • The Tsys will be higher, typically 350-600 K depending on the weather conditions and elevation.

Finishing

  • No IVS end message or sending off of logs is required. An email to Alet and Jon at Hart would be appreciated.
  • If the next experiment is using the S/X system, terminate the FS and restart with fs-mk5hb
/home/www/auscope/opswiki/data/pages/observing/kband.txt · Last modified: 2018/11/26 06:01 by Jamie McCallum