Differences between revisions 112 and 118 (spanning 6 versions)
⇤ ← Revision 112 as of 2008-01-24 11:46:28 →
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← Revision 118 as of 2008-03-20 10:59:46 → ⇥
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Editor: HansUngerechts
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Deletions are marked like this. Additions are marked like this.
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The 30-m telescope is now operating using the New Control System (NCS) (2005-11-30 HU) The 30-m telescope runs under the New Control System (NCS), see:
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NCS supports only source coordinates in Equatorial J2000.0 system.
(More systems will be made available as soon as possible)		 NCS supports only source coordinates in Equatorial J2000.0 system.  (More systems will be made available as soon as possible)
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 * Projection "Radio" (same offsets as in old CS) in Equatorial J2000.0 
* Projection "Radio" (same offsets as in old CS) in Equatorial J2000.0
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All 4 Switching Modes are supported by the NCS
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All 4 Switching Modes are supported by the NCS (total power, beam switching, wobbler switching, frequency switching.)  * total power
 * beam switching
 * wobbler switching
 * frequency switching
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 * (./) Observations with "rotated" wobbler and the bolometer are now possible within the pool; contact the pool manager, Stephane Leon, on how to prepare such observations. After finishing with rotated Wobbler, make sure that the operator puts the rotation back to '''exactly 0 degrees'''.  * Observations with "rotated" wobbler and the bolometer are possible within the pool; contact the pool manager, Stephane Leon, on how to prepare such observations. After finishing with rotated Wobbler, make sure that the operator puts the rotation back to '''exactly 0 degrees'''.
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 * Track  * Track
  * Frequency Switching
 * ON-OFF
  * Position Switching
  * Wobbler Switching
 * On-The-Fly Map
  * Heterodyne
   * Total Power (like Position Switching)
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 * ON-OFF
   * Position Switching		   * Bolometer
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 * On-The-Fly Map
   * Heterodyne
     * Total Power (like Position Switching)
     * Frequency Switching
   * Bolometer
     * Wobbler Switching
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(./) Automatic calibration and processing of heterodyne data using the MIRA software is in operation for all observing modes. MIRA can also be used manually and offline.

/!\ Online data processing, in some circumstances, still may have problems with scans extending over midnight. Please check data and report problems to Albrecht Sievers. It may be safer to avoid long scans extending over midnight.		 Automatic calibration and processing of heterodyne data using the MIRA software is in operation for all observing modes. MIRA can also be used manually and offline.
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/!\ On 30.10.2007 the GISMO bolometer has been installed. It is in the beam of single pixel or HERA observation for all declinations smaller than 25 degrees. There is no alarm, so astronomers should be aware of this (RM 30.10.2007)
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Available under NCS.		 (./) OK
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/!\ A glycol pump to regulate the temperature of the quadrupod is broken. The reparation could take a couple of weeks. Meanwhile focus and pointing scans must be repeated more often to correct the effect of possible thermal fluctuations. 3-Jan-08, JP [[BR]]
<!> Whereas the standard focus value for the bolometer is -3.5, with the glycol pump problem, '''the current values can oscillate between -1. and -3.''' 2007.01.23, SL [[BR]]
<!> With heterodyne receivers, e.g., during flux monitoring, focus has been about -0.0 mm (HU, 2008-01-24)
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(./) A, B, C, D receivers are supported by NCS for observations. A, B, C, D receivers are supported by NCS for observations.
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(./) Image/Signal gain-ratio calibration is supported by NCS. Image/Signal gain-ratio calibration is supported by NCS, processing in MIRA. It is highly recommended to use this.
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(./) A standard table of T_cold calibration temperatures for A, B, C, D receivers is implemented in NCS. This built-in table covers most frequencies. /!\ Outside this range, T_cold has to be set manually. A standard table of T_cold calibration temperatures for A, B, C, D receivers is implemented in NCS. This built-in table covers most frequencies. /!\ Outside this range, T_cold has to be set manually, see tables and plots:
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/!\ Note that the tables and plots at [http://gra-lx1.iram.es/mainWiki/ReceiverGroupColdloadPlots] appear to be out of date!

/!\ Tables and plots are now at [http://gra-lx1/mainWiki/ReceiverGroupColdLoadPlotsCurrent] 2007-10-11 dj		  http://gra-lx1/mainWiki/ReceiverGroupColdLoadPlotsCurrent (2007-10-11 dj)
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'''Note: the last 2 points need to be checked and maybe corrected by the RX group!'''
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(./) HERA is supported by the NCS. (2006-02 HU) Second polarization installed. [[BR]]
SSB tuning tables for standard frequencies. [[BR]]
Sideband rejections not determined (2004-12-01 AW). Use standard value of 0.1! [[BR]]
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Second polarization installed. [[BR]]
(./) One previously blind pixel is now fixed (2006-04). [[BR]]
SSB tuning tables for standard frequencies. [[BR]]
Sideband rejections not determined (2004-12-01 AW). Use standard value of 0.1! [[BR]]		 /!\ For HERA calibration, measured values of the load temperatures are automatically used!
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(./) For HERA calibration, measured values of the load temperatures are automatically used!

/!\ Watch the computer control of the derotator closely (2002-12-22). [[BR]]
/!\ Make sure the derotator tracking is stopped after observations, i.e., set to zero degrees in "frame". [[BR]]		 /!\ Watch the computer control of the derotator closely (2002-12-22). [[BR]] /!\ Make sure the derotator tracking is stopped after observations, i.e., set to zero degrees in "frame". [[BR]]
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HERA 2 is more noisy than HERA 1, limiting HERA2's useful frequency range to below about 242 GHz (2006-09-27 HU according to info from SN)[[BR]] /!\ HERA 2 is more noisy than HERA 1, limiting HERA2's useful frequency range to below about 242 GHz (2006-09-27 HU according to info from SN)[[BR]]
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'''Note: these comments on HERA need to be checked and, if necessary, corrected by the RX group!'''
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  A100 generally OK for pointing. (2003-11-12) [[BR]]
  B100 OK, is best for pointing. B100 is the standard reference for the heterodyne pointing model[[BR]]
    /!\ C150 often bad for pointing, ripple. (2002-07-16) [[BR]]
  D150 generally good performance for pointing.(2002-07-16) [[BR]]
  /!\ A230 often unstable, bad for pointing and flux monitoring. (2003-11-12) [[BR]]
  B230 OK [[BR]]
  /!\ C270 can be unstable and difficult for pointing. (2007-04-30) [[BR]]
  /!\ D270 can be unstable and difficult for pointing. (2002-07-16) [[BR]]

  With HERA pointing may be difficult using beam switch mode - total power mode may give better results but requires excellent weather [[BR]]  		    A100 generally OK for pointing. (2003-11-12) [[BR]]   B100 OK, is best for pointing. B100 is the standard reference for the heterodyne pointing model[[BR]]
   /!\ C150 often bad for pointing, ripple. (2002-07-16) [[BR]]   D150 generally good performance for pointing.(2002-07-16) [[BR]]   /!\ A230 often unstable, bad for pointing and flux monitoring. (2003-11-12) [[BR]]   B230 OK [[BR]]   /!\ C270 can be unstable and difficult for pointing. (2007-04-30) [[BR]]   /!\ D270 can be unstable and difficult for pointing. (2002-07-16) [[BR]]
   With HERA pointing may be difficult using beam switch mode - total power mode may give better results but requires excellent weather [[BR]]
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(./) Bolometer Observations are supported by the NCS.
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/!\ Mambo2: has been removed to install Gismo (RM 30.10.2007)
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Support by NCS:

 * (./) Continuum Backends for heterodyne receivers
 * (./) 4 MHz Filterbanks
 * (./) 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels
 * (./) WILMA for observations with HERA   * (./) VESPA
 * (./) ABBA for MAMBO bolometer
  * Continuum Backends for heterodyne receivers
 * 4 MHz Filterbanks
 * 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels
 * WILMA for observations with HERA
 * VESPA
 * ABBA for MAMBO bolometer
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/!\ The 30-m telescope is now operating using the New Control System (NCS) (2005-11-30 HU). Note that the NCS supports most essential features, but still has some limitations! See the NCS documentation for details, in particular links from the Wiki [https://mrt-lx1.iram.es/mainWiki/OperationNotesObservers NCS Operation Notes for Observers] /!\ The NCS supports most essential features, but still has some limitations; see the NCS documentation for details. (see links above)
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/!\ Pako does not run under the default gildas version on mrt-lx3, mrt-lx2.
Use '''gag_aug06''' before starting '''pako''' (2008-01-15 AS)		 /!\ Pako does not run under the default gildas version on mrt-lx3, mrt-lx2. Use '''gag_aug06''' before starting '''pako''' (2008-01-15 AS). ''Note: the instructions to start pako explicitly say to run it on mrt-lx1. The trick suggested by AS for mrt-lx2, mrt-lx3 may work, but it is not guaranteed.''
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 * (./) Remote observing via ''VNC'' is available from Granada, Grenoble, and Bonn. Coordinate with Walter Brunswig. Remote observing via ''VNC'' is available from Granada, Grenoble, and Bonn. Coordinate with Walter Brunswig.
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To see the changes between the actual and the last version, please see '''''Show Changes''''' in the Wiki Interface.
If you want to see the Revision History of this page, please see '''''Get Info''''' in the Wiki Interface.		 To see the changes between the actual and the last version, please see '''''Show Changes''''' in the Wiki Interface.  If you want to see the Revision History of this page, please see '''''Get Info''''' in the Wiki Interface.
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(./) : OK[[BR]]
/!\ : Warning[[BR]]
{X} : Error[[BR]]
 (./) : OK[[BR]] /!\ : Warning[[BR]] {X} : Error[[BR]]
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{{{(./) : OK {{{
(./) : OK
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Anchor(beginOfPage)

TableOfContents(3)

System - General

The 30-m telescope runs under the New Control System (NCS), see:

NCS supports only source coordinates in Equatorial J2000.0 system. (More systems will be made available as soon as possible)

Observations near and towards the Sun are not yet supported.

NCS supports observing modes and source offsets in:

  • Projection "Radio" (same offsets as in old CS) in Equatorial J2000.0
  • "true angle" horizontal
  • Nasmyth (receiver offsets)

All 4 Switching Modes are supported by the NCS

  • total power
  • beam switching
  • wobbler switching
  • frequency switching

  • Observations with "rotated" wobbler and the bolometer are possible within the pool; contact the pool manager, Stephane Leon, on how to prepare such observations. After finishing with rotated Wobbler, make sure that the operator puts the rotation back to exactly 0 degrees.

Observing modes supported by the NCS:

  • Calibrate (for heterodyne)
  • Pointing
  • Focus
  • Tip
  • Track
    • Frequency Switching
  • ON-OFF
    • Position Switching
    • Wobbler Switching
  • On-The-Fly Map
    • Heterodyne
      • Total Power (like Position Switching)
      • Frequency Switching
    • Bolometer
      • Wobbler Switching
  • VLBI

Automatic calibration and processing of heterodyne data using the MIRA software is in operation for all observing modes. MIRA can also be used manually and offline.

[#beginOfPage Back to top]

Antenna

(./) OK

[#beginOfPage Back to top]

Wobbler

(./) OK

[#beginOfPage Back to top]

Pointing Model and Focus

The Pointing Model is maintained with respect to the receiver B100. The misalignment and focus error (D-focus) of the other receivers with respect to B100 is the following: 

  Rx       misal.(")       date            D_focus(mm)       date
 A100     0.16 ±0.06     27-Feb-07,        +0.09 ±0.03     13-Mar-07
 A230     1.34 ±0.18     27-Feb-07,        +0.43 ±0.02     13-Mar-07
 B100     0.00                              0.00
 B230     1.74 ±0.16     27-Feb-07,        +0.40 ±0.10     17-Apr-07
 C150     1.26 ±0.24      5-Feb-07,        +0.64 ±0.13     17-Apr-07
 C270     0.78 ±0.18      5-Feb-07,        +0.36 ±0.15     17-Apr-07
 D150     1.03 ±0.13     12-Mar-07,        +0.26 ±0.02     12-Mar-07
 D270     1.40 ±0.19     12-Mar-07,        +0.18 ±0.05     12-Mar-07

heterodyne: last model update: 2007-10-23, 40 points, previous rms = 3.44", new rms = 1.69"

bolometer: last model update: 2007-11-16, 36 points, new rms < 1.5"

/!\ Pointing on spectral line sources like SiO masers is not yet supported by the data processing.

[#beginOfPage Back to top]

SIS Receivers

A, B, C, D receivers are supported by NCS for observations.

Image/Signal gain-ratio calibration is supported by NCS, processing in MIRA. It is highly recommended to use this.

A standard table of T_cold calibration temperatures for A, B, C, D receivers is implemented in NCS. This built-in table covers most frequencies. /!\ Outside this range, T_cold has to be set manually, see tables and plots:

/!\ Receiver C150 shows low continuum signal at the higher frequencies (>168 GHz). It has to be fully checked. Use D150 instead. (2005-11-16)

[#beginOfPage Back to top]

HERA

Second polarization installed. BR SSB tuning tables for standard frequencies. BR Sideband rejections not determined (2004-12-01 AW). Use standard value of 0.1! BR

/!\ For HERA calibration, measured values of the load temperatures are automatically used!

/!\ Watch the computer control of the derotator closely (2002-12-22). BR /!\ Make sure the derotator tracking is stopped after observations, i.e., set to zero degrees in "frame". BR

/!\ The automatic tuning of both HERA1 and 2 can be improved by manually changing the mixer current according to DJ; HERA Pool managers should be aware of this, and operators will receive training (2007-09-19 RM)

/!\ HERA 2 is more noisy than HERA 1, limiting HERA2's useful frequency range to below about 242 GHz (2006-09-27 HU according to info from SN)BR

[#beginOfPage Back to top]

Pointing and Flux monitoring with SIS receivers:

Continuum instability ("ripple") can occur with all receivers, making pointing and focusing difficult.

In general some receivers are better than others in this respect as summarized here:

  • A100 generally OK for pointing. (2003-11-12) BR B100 OK, is best for pointing. B100 is the standard reference for the heterodyne pointing modelBR /!\ C150 often bad for pointing, ripple. (2002-07-16) BR D150 generally good performance for pointing.(2002-07-16) BR /!\ A230 often unstable, bad for pointing and flux monitoring. (2003-11-12) BR B230 OK BR /!\ C270 can be unstable and difficult for pointing. (2007-04-30) BR /!\ D270 can be unstable and difficult for pointing. (2002-07-16) BR With HERA pointing may be difficult using beam switch mode - total power mode may give better results but requires excellent weather BR

[#beginOfPage Back to top]

Bolometers

Mambo1: OFFLINE

Mambo2 was re-installed and commissioned the week 13.11.2007/20.11.2007

[#beginOfPage Back to top]

Backends

  • Continuum Backends for heterodyne receivers
  • 4 MHz Filterbanks
  • 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels
  • WILMA for observations with HERA
  • VESPA
  • ABBA for MAMBO bolometer

  • /!\ the 100 kHz Filterbank is decommissioned. (RM, HU, 19.9.2007)

[#beginOfPage Back to top]

Computer/Software

/!\ The NCS supports most essential features, but still has some limitations; see the NCS documentation for details. (see links above)

/!\ Online data processing, in some circumstances, still may have problems with scans extending over midnight. Please check data and report problems to Albrecht Sievers. It may be safer to avoid long scans extending over midnight.

/!\ Pako does not run under the default gildas version on mrt-lx3, mrt-lx2. Use gag_aug06 before starting pako (2008-01-15 AS). Note: the instructions to start pako explicitly say to run it on mrt-lx1. The trick suggested by AS for mrt-lx2, mrt-lx3 may work, but it is not guaranteed.

[#beginOfPage Back to top]

Other Items

Remote observing via VNC is available from Granada, Grenoble, and Bonn. Coordinate with Walter Brunswig.

[#beginOfPage Back to top]

Updates/History

To see the changes between the actual and the last version, please see Show Changes in the Wiki Interface. If you want to see the Revision History of this page, please see Get Info in the Wiki Interface.

[#beginOfPage Back to top]

Legend

(./) : OKBR /!\ : WarningBR {X} : ErrorBR

The wiki markup of these icons is: 

(./) : OK
/!\ : Warning
{X} : Error

[#beginOfPage Back to top]

TelescopeSystemStatus (last edited 2025-01-25 17:12:49 by msanchez)