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Observations towards the Sun, observations of our Moon and satellites of other planets arenot yet supported. Observations towards the Sun, observations of our Moon, and of satellites of other planets are not yet supported.
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All 4 Switching Modes are supported by the NCS (total power, beam switching, wobbler switching, frequency switching.) Observations with "rotated" wobblerare not yet possible. All 4 Switching Modes are supported by the NCS (total power, beam switching, wobbler switching, frequency switching.) Observations with "rotated" wobbler are not yet possible.
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/!\ Pointing on spectral line sources like SiO masers is not available. /!\ Pointing on spectral line sources like SiO masers is not yet supported by the data processing.
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(./) Standard table of T_cold calibration temperatures (same as in old CS) is implemented in NCS; note that this covers only a limited standard range of frequencies. /!\ Outside this range, T_cold has to be set manually. (./) Standard table of T_cold calibration temperatures (same as in old CS) for A, B, C, D receivers is implemented in NCS; note that this covers only a limited standard range of frequencies. /!\ Outside this range, T_cold has to be set manually.
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== HERA ==
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Second polarization installed. /!\ One blind pixel. [[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 temperatues 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]]
/!\ Much higher noise in HERA 2 than HERA 1 when using Vespa. This is being investigated by S. Navarro [RM 30.6.2005][[BR]]
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== HERA ==

(./) HERA is supported by the NCS. (2006-02 HU)

Second polarization installed. /!\ One blind pixel. [[BR]]
SSB tuning tables for standard frequencies. [[BR]]
Sideband rejections not determined (2004-12-01 AW) [[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]]
/!\ Much higher noise in HERA 2 than HERA 1 when using Vespa. This is being investigated by S. Navarro [RM 30.6.2005][[BR]]

Anchor(beginOfPage)

TableOfContents(3)

System - General

/!\ The 30-m telescope is now operating using the New Control System (NCS) (2005-11-30 HU)

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

Observations towards the Sun, observations of our Moon, and of satellites of other planets 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 are not yet possible.

Observing modes supported by the NCS:

  • Calibrate (for heterodyne)
  • Pointing
  • Focus
  • Tip (for bolometer)
  • Track (Frequency Switching)
  • ON-OFF (Position Switching or Wobbler Switching)
  • On-The-Fly Map
  • VLBI

/!\ A prototype of automatic processing of heterodyne data using the MIRA software is available. Its features will be expanded as soon as possible. MIRA can also be run manually and offline. (2006-02 HU)

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Antenna

(./) OK

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Wobbler

Available under NCS.

/!\ Wobbler rotation (actually, secondary rotation) not yet available under NCS.

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Pointing Model

heterodyne: OK, (last model update: 2006-01-30 15:16).

bolometer: OK, (last model update: 2006-02-09 08:35).

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

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SIS Receivers

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

/!\ Some problems reported from B100: difficult to lock/tune at some frequencies, higher Trx, ...

/!\ Image/Signal gain-ratio calibration is not yet supported by NCS.

(./) Standard table of T_cold calibration temperatures (same as in old CS) for A, B, C, D receivers is implemented in NCS; note that this covers only a limited standard range of frequencies. /!\ Outside this range, T_cold has to be set manually.

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

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HERA

(./) HERA is supported by the NCS. (2006-02 HU)

Second polarization installed. /!\ One blind pixel. 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 temperatues 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 /!\ Much higher noise in HERA 2 than HERA 1 when using Vespa. This is being investigated by S. Navarro [RM 30.6.2005]BR

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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 then others in this respect as summarized here:

  • A100 generally OK for pointing. (2003-11-12) BR B100 OK, is best for pointing. 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 very bad for pointing at 265 Ghz. (2002-07-16) BR /!\ D270 can be unstable and difficult for pointing. (2002-07-16) BR

    HERA pointing difficulties using beam switch mode - total power mode gave better results but requires excellent weather BR Wobbler switching may avoid ripple, beam switching is most sensitive to ripple

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Bolometers

(./) Bolometer Observations are supported by the NCS.

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Backends

Support by NCS:

  • (./) Continuum Backends for single-pixel heterodyne receivers

  • (./) 4 MHz Filterbanks

  • (./) 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels

  • /!\ 100 kHz Filterbank not yet supported by NCS

  • (./) WILMA is supported by NCS for observations with HERA (2006-02 HU)

  • (./) VESPA

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Computer/Software

/!\ The 30-m telescope is now operating using the New Control System (NCS) (2005-11-30 HU). Note that the NCS so far supports only a restricted set of features!

[#beginOfPage Back to top]

Other Items

  • /!\ Remote observing is not yet possible with the NCS

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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.

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Legend

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

The wiki markup of these icons is:

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

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TelescopeSystemStatus (last edited 2017-02-10 09:04:18 by HansUngerechts)