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: http://www.naic.edu/~astro/RXstatus/327/327greg.shtml
Дата изменения: Unknown Дата индексирования: Sun Feb 3 22:57:17 2013 Кодировка: Поисковые слова: п п п п п п c 1999 s4 linear |
327-MHz Gregorian
Basic Information | Calibration & Beam Parameters RFI Situation Recent Events Receiver History Contact Info |
Frequency Range (GHz): | 0.302 - 0.352 |
Name and Number: |
327-MHz Gregorian (P Band) |
Measured Sensitivity (K/Jy): | 10* |
Measured System Temp (K): | 110-135* |
Native Polarization:
Dual linear
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|
Beam Size (at 0.327 GHz): | 14' x 15' |
Available Filters: |
50 MHz (302 - 352 MHz) 30 MHz (312 - 342 MHz) Plot of frequency response with the 30 MHz filter can be found here |
Warnings and Important Notes:
click here |
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2. Calibration & Beam Parameters:
Gain and Tsys | Cal Values | Beam Maps | Polarization | Misc. Info |
Tsys values include the contribution from the sky (i.e., Tsky is not
subtracted out). Detailed
information here.
Noise diode 1:
Left: 95.5 K
Right: 102.55 K
Detailed information
here.
Not available. However, information on the coma parameter, sidelobe
strength and beam efficiency can be found here.
Full polarization characterization not yet available.
The P band is now quite clean, specially at night, compared to the 10-MHz band centered at 430 MHz. There was previously a 2-MHz comb originating in the radar system, this has been dealt with successfuly, the comb is still detectable, but very weak.
During my preliminary observations with
this receiver I have seen very strong interference at
307 MHz. This is already outside the nominal bandpass, but even with
more than 20 dB of attenuation, this line can completely
saturate the system. In such situations, one should increase the central
(sky) frequency, or, if observing with the WAPP, use a filter with 25
MHz or less of bandwidth.
This is an UNIDENTIFIED radio FREQUENCY INTERFERENCE.
For RFI with known identifications, click here.
Daily RFI monitoring plots for the past several
years from the Observatory "hill-top" monitoring system can be found in
binders in either the telescope Control Room or by asking
the Arecibo Spectrum Manager.
July 2002: Room temperature receiver installed.
The 327 receiver had been removed in 2001 to be worked on. It was re-installed in July 2002 with a room temperature receiver. The initial plan was to make it a cooled receiver, however leaks in the cryogenic dewar used to cool the receiver's LNA's have made that impossible. The current plan calls for the installation of a new receiver.
For further information on this receiver, please contact Julia Deneva