Occurrence of rfi versus frequency by month

last month added: jul17

    Histograms of interference versus frequency are computed for the data acquired on the telescope using the correlator. For each scan of N separate integrations (typically 1 second) the rms/Mean by channel is computed. A linear baseline is used to remove any zenith angle dependence.

     Histograms are then made of the number of rfiCnts/TotalCnts by frequency channel. Any rms/Mean greater than 3 times the expected sigma is called rfi. This sigma is computed using the bandwidth, integration time, and corrections for: 3/9 level sampling, hanning smoothing, and the instrumental bandwidth of the channels. Any band passes that have more than 80% of their channels "bad" are not included in the rfi or total counts. The histograms have .1 Mhz resolution. The rfi count in the .1 Mhz channel is incremented by 1 (and only 1) if any of the telescope channels within the .1 Mhz bin exceed 3 sigma.

    There is a cumulative plot for the year followed by monthly plots. Each plot has the fractional occurrence of rfi in black. The blue histogram is the total number of counts (nonrfi + rfi) in each bin. The vertical scale on the right tells the total counts per bin. The red line is a histogram of the number of times a bandpass was rejected because more than 80% of the frequency bins were above 3 sigma. This histogram has been scaled to: badcnts/(total counts + badcounts). If there are a large fraction of red lines it may be because of some mapping programs that include large continuum sources or have large za variations for the strip (some of the alfa proposals).

PLOTS OF rfi by year and month.

The entries without links have no data for that month. The 611 and 327 receiver have not been installed a large fraction of the time. Occasionally the rfi monitoring will take data on the receiver when it is not there (so there is just a load connected). This depends on whether I remember to update the receiver file to use (and that electronics reminds me that they have put it up or down). Sband 1800-3100 switched from just sband narrow (2320-2420) to the full range of 1800 to 3100 sept01 when the sband wide receiver was reinstalled. The pattern of dips in the total counts by bin (blue lines) is from the x111 datataking. It steps by 23 Mhz giving an overlap of 1 Mhz and the plotting ignores 1 Mhz from the edge (do to filter rolloff). If you use ghostview to look at the plots, clicking on a mouse button will blowup the region centered on the mouse.
 

Why to do the plots look lousy :

Fractional Occurrence of Rfi
 
327 
(310-340)
430 
(410-445)
800
(700-800)
lband 
(1100-1800)
lband (blowup) 
(1250-1450)
alfa 
(1220-1520)
sband
(1800-3100)
sbh 
(3000-4000)
cband 
(4000-6000)
cb Hi 
(6000-8000)
xband 
(8000-10000)




RFI BY YEAR








YrToDate
YrToDate

YrToDate
YrToDate
YrToDate
YrToDate
YrToDate
YrToDate
YrToDate
YrToDate

Yr2016
Yr2016

Yr2016
Yr2016
Yr2016
Yr2016
Yr2016
Yr2016
Yr2016
Yr2016

Yr2015
Yr2015

Yr2015
Yr2015
Yr2015
Yr2015
Yr2015
Yr2015
Yr2015
Yr2015

Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014
Yr2014

Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013
Yr2013

Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012
Yr2012

Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011
Yr2011

Yr2010
Yr2010
Yr2010
Yr2010
Yr2010
Yr2010
Yr2010

Yr2010
Yr2010
Yr2010

Yr2009
Yr2009
Yr2009
Yr2009
Yr2009
Yr2009
Yr2009

Yr2009
Yr2009
Yr2009

Yr2008
Yr2008
   611
Yr2008
Yr2008
Yr2008
Yr2008
Yr2008
Yr2008
Yr2008
Yr2008

Yr2007
Yr2007
Yr2007
Yr2007
Yr2007
Yr2007
Yr2007

Yr2007
Yr2007
Yr2007

Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006
Yr2006

Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005
Yr2005

Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004
Yr2004

Yr2003
Yr2003
Yr2003
Yr2003
Yr2003

Yr2003
Yr2003
Yr2003

Yr2003

Yr2002
Yr2002
Yr2002
Yr2002
Yr2002

Yr2002
Yr2002
Yr2002

Yr2002
 
 Yr2001
 Yr2001
Yr2001
Yr2001
Yr2001

 Yr2001
 
 Yr2001

 




RFI BY MONTH








sep17
sep17
sep17
sep17
sep17
sep17
sep17
sep17
sep17

aug17
aug17
aug17
aug17
aug17
aug17
aug17
aug17
aug17

jul17
jul17
jul17
jul17
jul17
jul17
jul17
jul17
jul17

jun17
jun17
jun17
jun17
jun17
jun17
jun17
jun17
jun17

may17
may17
may17
may17
may17
may17
may17
may17
may17

apr17
apr17
apr17
apr17
apr17
apr17
apr17
apr17
apr17

mar17
mar17
mar17
mar17
mar17
mar17
mar17
mar17
mar17

feb17
feb17
feb17
feb17
feb17
feb17
feb17
feb17
feb17

jan17
jan17
jan17
jan17
jan17
jan17
jan17
jan17
jan17

dec16
dec16
dec16
dec16
dec16
dec16
dec16
dec16
dec16

nov16
nov16
nov16
nov16
nov16
nov16
nov16
nov16
nov16

oct16
oct16
oct16
oct16
oct16
oct16
oct16
oct16
oct16
oct16

sep16
sep16
sep16
sep16
sep16
sep16
sep16
sep16
sep16

aug16
aug16
aug16
aug16
aug16
aug16
aug16
aug16
aug16
aug16

jul16
jul16

jul16
jul16
jul16
jul16
jul16
jul16
jul16
jul16

jun16
jun16

jun16
jun16
jun16
jun16
jun16
jun16
jun16
jun16

may16
may16

may16
may16
may16
may16
may16
may16
may16
may16

apr16
apr16

apr16
apr16

apr16
apr16
apr16
apr16
apr16

feb16
feb16

feb16
feb16
feb16
feb16
feb16
feb16
feb16
feb16

jan16
jan16

jan16
jan16
jan16
jan16
jan16
jan16
jan16
jan16

dec15
dec15

dec15
dec15
dec15
dec15
dec15
dec15
dec15
dec15

nov15
nov15

nov15
nov15
nov15
nov15
nov15
nov15
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oct15
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oct15
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oct15
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sep15
sep15

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aug15
aug15

aug15
aug15
aug15
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aug15
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jul15
jul15

jul15
jul15
jul15
jul15
jul15
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jul15

jun15
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jun15
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jun15
jun15

may15
may15

may15
may15
may15
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may15
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may15

apr15
apr15

apr15
apr15
apr15
apr15
apr15
apr15
apr15
apr15

mar15
mar15

mar15
mar15
mar15
mar15
mar15
mar15
mar15
mar15

feb15
feb15

feb15
feb15
feb15
feb15

feb15
feb15
feb15

jan15
jan15

jan15
jan15
jan15
jan15

jan15
jan15
jan15

dec14
dec14

dec14
dec14
dec14
dec14

dec14
dec14
dec14

nov14
nov14

nov14
nov14
nov14
nov14

nov14
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oct14
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oct14
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oct14
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sep14
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aug14
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aug14
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jul14
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jul14
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jun14
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jun14
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jun14
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jun14
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may14
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may14
may14
may14
may14

may14
may14
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apr14
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apr14
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mar14
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mar14
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mar14
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feb14
feb14

feb14
feb14
feb14
feb14

feb14
feb14
feb14

jan14
jan14

jan14
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jan14
jan14

jan14
jan14
jan14

dec13
dec13

dec13
dec13
dec13
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dec13
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nov13
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nov13
nov13
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nov13
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aug13
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jul13
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may13
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apr13
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apr13
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mar13
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mar13
mar13
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feb13
feb13
feb13
feb13
feb13
feb13
feb13

feb13
feb13
feb13

jan13
jan13
jan13
jan13
jan13
jan13
jan13
jan13
jan13
jan13
jan13

dec12
dec12
dec12
dec12
dec12
dec12
dec12
dec12
dec12
dec12
dec12

nov12
nov12
nov12
nov12
nov12
nov12
nov12
nov12
nov12
nov12
nov12

oct12
oct12
oct12
oct12
oct12
oct12
oct12
oct12
oct12
oct12
oct12

sep12
sep12
sep12
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sep12
sep12
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sep12
sep12
sep12
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aug12
aug12
aug12
aug12
aug12
aug12
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aug12
aug12
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aug12

jul12
jul12
jul12
jul12
jul12
jul12
jul12
jul12
jul12
jul12
jul12

jun12
jun12
jun12
jun12
jun12
jun12
jun12
jun12
jun12
jun12
jun12

may12
may12
may12
may12
may12
may12
may12
may12
may12
may12
may12

apr12
apr12
apr12
apr12
apr12

apr12
apr12
apr12
apr12
apr12

mar12
mar12
mar12
mar12
mar12
mar12
mar12
mar12
mar12
mar12
mar12

feb12
feb12
feb12
feb12
feb12
feb12
feb12
feb12
feb12
feb12
feb12

jan12
jan12
jan12
jan12
jan12
jan12
jan12
jan12
jan12
jan12
jan12

dec11
dec11
dec11
dec11
dec11
dec11
dec11
dec11
dec11
dec11
dec11

nov11
nov11
nov11
nov11
nov11
nov11
nov11
nov11
nov11
nov11
nov11

oct11
oct11
oct11
oct11
oct11
oct11
oct11
oct11
oct11
oct11
oct11

sep11
sep11
sep11
sep11
sep11
sep11
sep11
sep11
sep11
sep11
sep11

aug11
aug11
aug11
aug11
aug11

aug11
aug11
aug11
aug11
aug11

jul11
jul11
jul11
jul11
jul11

jul11
jul11
jul11

jul11

jun11
jun11
jun11
jun11
jun11
jun11
jun11
jun11
jun11
jun11
jun11

may11
may11
may11
may11
may11
may11
may11
may11
may11
may11
may11

apr11
apr11
apr11
apr11
apr11
apr11
apr11

apr11

apr11

mar11
mar11
mar11
mar11
mar11
mar11
mar11

mar11

mar11

feb11
feb11
feb11
feb11
feb11
feb11
feb11

feb11

feb11

jan11
jan11
jan11
jan11
jan11
jan11
jan11

jan11

jan11

dec10
dec10
dec10
dec10
dec10
dec10
dec10

dec10

dec10

nov10
nov10
nov10
nov10
nov10
nov10
nov10

nov10

nov10

oct10
oct10

oct10
oct10
oct10
oct10

oct10

oct10

sep10
sep10
sep10
sep10
sep10
sep10
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sep10

sep10

aug10
aug10

aug10
aug10
aug10
aug10

aug10

aug10

jul10
jul10

jul10
jul10
jul10
jul10

jul10

jul10

jun10
jun10

jun10
jun10
jun10
jun10

jun10



may10
may10
may10
may10
may10
may10
may10

may10
may10
may10

apr10
apr10
apr10
apr10
apr10
apr10
apr10

apr10
apr10
apr10

mar10
mar10

mar10
mar10
mar10
mar10

mar10
mar10
mar10

feb10
feb10

feb10
feb10
feb10
feb10

feb10
feb10
feb10

jan10
jan10
jan10
jan10
jan10
jan10
jan10

jan10
jan10
jan10

dec09
dec09
dec09
dec09
dec09
dec09
dec09

dec09
dec09
dec09

nov09
nov09
nov09
nov09
nov09
nov09
nov09

nov09
nov09
nov09

oct09
oct09
oct09
oct09
oct09
oct09
oct09

oct09
oct09
oct09

sep09
sep09
sep09
sep09
sep09
sep09
sep09

sep09
sep09
sep09

aug09
aug09
aug09
aug09
aug09
aug09
aug09

aug09
aug09
aug09

jul09
jul09
jul09
jul09
jul09
jul09
jul09

jul09

jul09

jun09
jun09
jun09
jun09
jun09
jun09
jun09

jun09
jun09
jun09

may09
may09

may09
may09
may09
may09

may09
may09
may09

apr09
apr09

apr09
apr09
apr09
apr09

apr09

apr09

mar09
mar09

mar09
mar09
mar09
mar09

mar09
mar09
mar09

feb09
feb09

feb09
feb09
feb09
feb09

feb09

feb09

jan09
jan09

jan09
jan09
jan09
jan09

jan09
jan09
jan09

dec08
dec08

dec08
dec08
dec08
dec08

dec08
dec08
dec08

nov08
nov08

nov08
nov08
nov08
nov08

nov08
nov08
nov08

oct08
oct08

oct08
oct08
oct08
oct08

oct08
oct08
oct08

sep08
sep08

sep08
sep08
sep08
sep08

sep08

sep08

aug08
aug08

aug08
aug08
aug08
aug08

aug08

aug08

jul08
jul08

jul08
jul08
jul08
jul08

jul08

jul08

jun08
jun08

jun08
jun08
jun08
jun08
jun08
jun08

jun08

may08
may08

may08
may08
may08
may08

may08

may08

apr08
apr08

apr08
apr08
apr08
apr08
apr08
apr08

apr08

mar08
mar08

mar08
mar08
mar08
mar08

mar08

mar08

feb08
feb08

feb08
feb08
feb08
feb08

feb08

feb08

jan08
jan08

jan08
jan08
jan08
jan08

jan08

jan08

dec07
dec07

dec07
dec07
dec07
dec07

dec07



apr07
apr07
    611
apr07
apr07
apr07
apr07

apr07
apr07
apr07

mar07
mar07
mar07
mar07
mar07
mar07
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mar07
mar07
mar07

feb07
feb07
feb07
feb07
feb07
feb07
feb07

feb07
feb07
feb07

jan07
jan07
jan07
jan07
jan07
jan07
jan07

jan07
jan07
jan07

dec06
dec06
dec06
dec06
dec06
dec06
dec06
dec06
dec06
dec06
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nov06
nov06
nov06
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oct06
oct06
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oct06
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oct06
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sep06
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aug06
aug06
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jul06
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jul06
jul06
jul06

jun06
jun06
jun06
jun06
jun06
jun06
jun06
jun06
jun06
jun06
jun06

may06
may06
may06
may06
may06
may06
may06
may06
may06
may06
may06

apr06
apr06
apr06
apr06
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apr06
apr06
apr06

mar06
mar06
mar06
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mar06
mar06

feb06
feb06
feb06
feb06
feb06
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feb06
feb06
feb06
feb06

jan06
jan06
jan06
jan06
jan06
jan06
jan06
jan06
jan06
jan06
jan06

dec05
dec05
dec05
dec05
dec05
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nov05
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oct05
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sep05
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aug05
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jul05
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jun05
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may05
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may05
may05
may05
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may05
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apr05
apr05
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mar05
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feb05
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jan05
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jan05
jan05
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dec04
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nov04
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oct04
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sep04
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sep04
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aug04
aug04
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aug04
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jul04
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jul04
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jun04
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jun04
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jun04
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may04
may04
may04
may04
may04

may04
may04
may04
may04
may04

apr04
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apr04
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apr04
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apr04
apr04
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mar04
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mar04
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mar04
mar04
mar04

feb04
feb04
feb04
feb04
feb04

feb04
feb04
feb04
feb04
feb04

jan04
jan04
jan04
jan04
jan04

jan04
jan04
jan04

jan04

dec03
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dec03
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dec03
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dec03

nov03
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nov03
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nov03

oct03
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oct03
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oct03

sep03
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sep03
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sep03

aug03
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Year 2011 comments:


Year 2010 comments:


Year 2009 comments:


Year 2008 comments


Year 2005 comments

  • mar05 - The rms for the wapp data was computed and then stored in the old interim correlator format back out on disc. The frequency flip was occasionally getting screwed up. Fixed the problem and then processesed the data nov04 though feb05. The lbw/alfa birdies should now be in the correct positions.
  • feb05  - updated exclude criteria for wapps. Some patterns were being included that shouldn't have been. Reprocessed the data.
  • Year 2004 comments

  • nov04 - include alfa data and wapp data for the other recievers.
  • feb04 - 6 to 8 Ghz (cbh) installed.
  • Year 2003 comments

  • sep03 - xband. the blocks of 25 Mhz that have rejected bands (red) is from the lousy pointing at xband. Some users were doing on/offs on strong continuum sources. The power in the on varied over the scan. When computing the rms by channel you got large values. Since the continuum source affect all channels, the band got rejected (red gt 85% of channels bad)..
  • feb03 - telescope shutdown. drift scans 327,cband (4800) , and lbndrift.
  • feb03 - sbwide,lbw switch in filters while stepping. especially sbwide..
  • Year 2002 comments:

  • sep02 327 data was being taken at the wrong frequency. Was using 260IF and trying to get 4 sub bands out of it. When the new receiver/filters were installed in jul2002, the file x111auto.dat was not updated for the new bandwidths. Was corrected on 16sep02.
  • aug02 327 2 Mhz comb from 430 waveguide power monitor.
  • Year 2001 comments:

  • jan-mar 1366,1382 radar (more info)
  • March:  seti observations, not much data.
  • April:  Tv station at 1408 (more info)
  • May: Tv station at 1408 (see above link)
  • July: aeronomy runs, not much data.
  • August:  A1459 baseline instabilities (1340-1440) from air conditioner in dome (more info).
  • Sept: A1459 baseline ripples (see above).
  • sband wide. The Yr2001 data shows that the fraction of band passes that were rejected (the red lines) stays high up to 2600Mhz and then drops to zero.  I think this is because the birdies at 1940 Mhz are overloading some components after the 1 Ghz filter of the 10 Ghz upconverter. When you are farther than 500 Mhz from 1940, the cellular phones at 1940 start to get filtered out. The culprit is probably the fiber optic link. When the power levels are adjusted, the total power is used. It is high from the 1940 birdie so the spectral density for the rest of the band gets  set to low.
  • processing: rfi/rms/mkyr.pro
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