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.
- For the current daily average 327-MHz RFI plot from the Arecibo
"hill-top" monitoring system, click here .
- For the current frequency v time 327-MHz RFI plot
from the Arecibo
"hill-top" monitoring system, click here .
- For the current frequency v time 327-MHz RFI plot (with band-pass
correction)
from the Arecibo
"hill-top" monitoring system, click here .
- For the current daily rms/mean v frequency 327-MHz RFI plot
from the Arecibo
"hill-top" monitoring system, click here .
The occurrence of RFI versus frequency by month and year since Jan
2001 can be found
via the 327 link on this web page.
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4. Recent Events:
Link to electronics department containing updated
receiver log
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5. Receiver History:
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.
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6. Contact Info:
For further information on this receiver, please contact
Julia Deneva
deneva (append @naic.edu)
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