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 [http://www.iram.es/IRAMES/ncs30m/ NCS documentation]

 [http://mrt-lx1/mainWiki/FrontPage/ Wiki with up-to-date Notes on NCS (only available locally)]


NCS supports only source coordinates in Equatorial J2000.0 system.

NCS supports observing modes and source offsets in:
 * Projection "Radio" in Equatorial J2000.0 (same as in old CS)
 * "true angle" horizontal
 * Nasmyth (receiver ofsets)

(More systems will be made available as soon as possible)

All 4 Switching Modes are supported by the NCS (total power, beam switching, wobbler switching, frequency switching.)

Observing modes supported by the NCS:

 * Calibrate (for hetrodyne)
 * Pointing
 * Focus
 * Tip (for bolometer)
 * Track (Frequency Switching)
 * ON-OFF (Position Switching or Wobbler Switching)
 * On-The-Fly Map
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/!\ Observing configuration sometimes is not transfered to the wobbler control system and when fails W. Brunswig has to restart his communication programs (since January 2005). Wobbler config. can be set manually by operator Available under NCS.
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Wobbler rotation implemented. Current range: +/- 60deg (2004-12-01 AW) /!\ Wobbler rotation (actually, secondary rotation) not yet available under NCS.
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heterodyne: OK (last model update: 2005-04-30 ).[[BR]]
bolometer: OK (last model update: 2004-11-02 ).
heterodyne: usable, but should be improved (last model update: 2005-11).
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bolometer: OK, but could be improved (last model update: 2005-11).
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/!\ Operator/AOD: Check regularly that automatic P4 P5 is working (2002-12-13).[[BR]]
{X} Narrowband continuum pointing (for SiO masers) is out of service! (2003-07-09, 2003-07-30)
/!\ Operator/AOD: Check regularly that secondary/ spindle control, weather data for refraction correction, and automatic P4/P5 are working correctly -- if necessary ask a member of the NCS team for instructions about this (2005-12).[[BR]]

/!\ Pointing on spectral line sources like SiO masers is not yet available under NCS.
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A, B, C and D receivers are aligned within  3", checked (2003-09-24) A, B, C and D receivers are aligned within 3", checked (2003-09-24)
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/!\ Receiver C150 show low continuum signal at the higher frequencies (>168 GHz)
It has to be fully checked. Use D150 instead. (2005-11-16)
(./) A, B, C, D receivers are supported by NCS for observations.
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Calibration Tcold temperatures have been checked by receiver group.[[BR]]
New scaling factor of 0.94 has been implemented into obs.[[BR]]
Obs Tcold should be ok (2005-06-28)
/!\ Image/Signal gain-ratio calibration is not yet supported by NCS.
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{X} B100 out of operation for at least several days due to broken Gunn oscillator (RM 2005-11-22) 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.

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

/!\ HERA is not yet supported by NCS. (to be done for 2006, February).
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 In general some receivers are better then others in this respect as summarized here:
In general some receivers are better then others in this respect as summarized here:
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    B100 OK, is best for pointing [[BR]]     B100 OK, is best for pointing, but is out of operation (2005-11-30)! [[BR]]
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    HERA pointing difficulties using beam switch mode - total power mode gave better results but requires excellent weather
[[BR]] Wobbler switching may avoid ripple, beamswitching is most sensitive to ripple

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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/!\ HERA is not yet supported by NCS. To be done for 2006-02.
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Bolometer Observations are supported by the NCS.
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 256 MHz shift in 100kHz FB header (AW 2004-12-01) [[BR]]
 Software and/or hardware problem in the 1MHz FB - problem is currently investigated (AW 2004-12-01) [[BR]]
 Spikes in VESPA at intersection of different units (AW 2004-12-01) [[BR]]
Support by NCS:

 * (./) Continuum Backends for single-pixel heterodyne receivers supported by NCS
 * (./) 4 MHz Filterbanks supported by NCS
 * (./) 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels; /!\ without frequency shifts.
 * /!\ 100 kHz Filterbank not yet supported by NCS
 * /!\ WILMA not yet supported by NCS
 * (./) VESPA supported by NCS
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/!\ The 30-m telescope is now operating using the New Control System (NCS) (2005-11-30 HU)
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Note that the NCS so far supports only a restricted set of features!

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.

NCS supports observing modes and source offsets in:

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

(More systems will be made available as soon as possible)

All 4 Switching Modes are supported by the NCS (total power, beam switching, wobbler switching, frequency switching.)

Observing modes supported by the NCS:

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

[#beginOfPage Back to top]

Antenna

(./) OK

[#beginOfPage Back to top]

Wobbler

Available under NCS.

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

[#beginOfPage Back to top]

Pointing Model

heterodyne: usable, but should be improved (last model update: 2005-11).

bolometer: OK, but could be improved (last model update: 2005-11).

/!\ Operator/AOD: Check regularly that secondary/ spindle control, weather data for refraction correction, and automatic P4/P5 are working correctly -- if necessary ask a member of the NCS team for instructions about this (2005-12).BR

/!\ Pointing on spectral line sources like SiO masers is not yet available under NCS.

[#beginOfPage Back to top]

SIS Receivers

A, B, C and D receivers are aligned within 3", checked (2003-09-24)

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

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

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.

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

/!\ HERA is not yet supported by NCS. (to be done for 2006, February).

[#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 then others in this respect as summarized here:

  • A100 generally OK for pointing. (2003-11-12) BR B100 OK, is best for pointing, but is out of operation (2005-11-30)! 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

[#beginOfPage Back to top]

HERA

/!\ HERA is not yet supported by NCS. To be done for 2006-02.

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 /!\ With VESPA, the maximum of 4 spectra per pixel can be used. 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 /!\ When using HERA 1 and 2 configure only 1 Channel for continuum observations in OBS, never-the-less the continuum drifts of all channels are reduced (calibrated) by ODP [AS 11.10.2005]

[#beginOfPage Back to top]

Bolometers

Bolometer Observations are supported by the NCS.

Mambo II is installed and ready for operation (AW 2004-12-01)

[#beginOfPage Back to top]

Backends

Support by NCS:

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

  • (./) 4 MHz Filterbanks supported by NCS

  • (./) 1 MHz Filterbank in parts of 256, 512, 768, or 1024 channels; /!\ without frequency shifts.

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

  • /!\ WILMA not yet supported by NCS

  • (./) VESPA supported by NCS

[#beginOfPage Back to top]

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

OK

[#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)