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[IDD #KUD-512290]: Backup NOAAPort source ?



Hi Jerry,

First, thanks for a detailed description of the NOAAPort ingest problems
you are experiencing -- it should help me to create an appropriate mental
model for what may be going on.

Second, your C/N (Carrier to Noise) is _terrible_!  The target C/N for
WFO NOAAPort installations is 17.  The C/N for here and LSU/SRCC varies
between the high 15s to just over 17.  I have attached a (python-generated)
plot that contains a time series of C/N as measured off of one of our
Novra S300Ns.  I have also attached the same kind of plot for the LSU/SRCC
installation.

I'm heading into the office now (still at home), so I will close out this
reply and pick-up comments a bit later.

Cheers,

Tom

> We first started having intermittent problems recently with data flow slowing 
> to a
> trickle, then it would clear up.  After a couple times of it happening we 
> found that the
> drops correlated with times when the SBN uplink was changed to the backup in 
> WV.  ie
> this day:
> 
> > Mon Mar 21 13:12:11 2016 GMT
> >
> > NOUS72 KNCF 211311
> > ADMNCF
> > .
> > DUE TO SCHEDULED MAINTENANCE, THE NCF WILL BE
> > SWITCHING THE SBN UPLINK FROM THE PRIMARY MASTER GROUND
> > STATION IN HAUPHAUGE, NY TO THE BACKUP MASTER GROUND
> > STATION IN FAIRMONT, WV ON MONDAY March 21ST AT 13:15Z.
> >
> > And again this day:
> >
> > Tue Apr 12 14:52:14 2016 GMT
> >
> > NOUS72 KNCF 121450
> > ADMNCF
> > .
> > THE SBN UPLINK HAS BEEN SUCCESSFULLY SWITCHED TO THE
> > BACKUP MASTER GROUND STATION IN FAIRMONT, WV.
> 
> When data recovered it matched when they did their switches back (which we 
> didn't log).
> 
> THEN lastly starting the evening of April 20th (3zish?) the loss of data 
> started again
> and we have not recovered.  It is unknown if they switched to the backup site 
> or not --
> we were assuming so but.. ?  I will see if I can get an answer from someone 
> about that
> unless maybe you know?
> 
> What we noted when the data loss occurred while they were on their backups 
> was a drop in
> carrier to noise from around 10.3 to ~9.2.
> 
> We do not have logs of our normal signal levels or what they were during the 
> outage
> times, but from 4/21 through yesterday before we tried swapping out some 
> splitters our
> stats were showing similar to this:
> 
> 
> address@hidden ~]$ cmcs -ip 192.168.1.10 -pw Novra-S2 -shsat
> Satellite Interface Settings:
> 
> Receiver MAC Address: 00-06-76-05-01-f3
> Receiver Mode:        DVBS2
> Frequency:    1110.0 MHz
> Symbol Rate:  30.001 Msps (Auto)
> ModCod:       2/3 16PSK
> Gold code:    0
> Input Stream Filter:  On
> Input Stream ID:      18
> 
> Signal Lock:  On
> Data Lock:    On
> Uncorrectable Rate:   0/Second
> Packet Error Rate:    0.0000e+00
> 
> Carrier to Noise C/N: 9.3dB
> Signal Strength:      -23 dBm
> 
> 
> 
> What we have tried:
> 
> Peaking the antenna â it was already at it's best and has been.
> 
> We noticed that our input signal strength was very high   -23 dBm â.. we 
> read through
> the Novra manual, and saw that the recommended input frequency be between  
> -70 dBm to
> -25 dBm.   So we thought we may be over driving it.  (Remember, we have a 6.3 
> meter
> antenna receiving the signal for this.)   We tried an in line attenuator, but 
> that did
> not work, but we noticed that putting in a 4 way splitter attenuated the 
> signal enough
> to get us into the right range  â. signal strength went down to -27 dBm, 
> and our Eb/No
> improved.   We have tried various splitters to adjust the input signal, but 
> the sweet
> spot seems to be the 4 way splitter.   Unfortunately, we are still missing 
> lots of
> data.
> 
> We also recalled the problem you described with probing the Novra causing 
> missed data.
> We turned off our Novra probes for a couple of hours.   It did not make a 
> difference.
> 
> We have a call out to Quorum to see if they have any ideas.   Do you know if 
> Quorum
> makes a Noaaport DVBS2 demodulator?  We may try to get a more 
> robust/enterprise quality
> demodulator.
> 
> We may also try changing which Novra box powers the LNB to see if that fixes 
> the problem.
> 
> If you guys have any ideas, please send them out wayâ.
> 
> Jerry
> --
> Jerrold Robaidek                              Email:  address@hidden
> SSEC Data Center                              Phone: (608) 262-6025
> University of Wisconsin                       Fax: (608) 263-6738
> Madison, Wisconsin
> 
> On Apr 27, 2016, at 4:44 PM, Unidata IDD Support <address@hidden> wrote:
> 
> > Hi Rosie,
> >
> > re:
> >> Awesome. Thanks Tom!
> >
> > No worries.
> >
> > I'm curious about what is happening on both of your NOAAPort ingest 
> > machines.
> > Can you share any specifics?
> >
> > The reason for our concern is that the NOAAPort-derived datastreams have
> > been ingested at three geographically diverse sites, and that arrangement
> > has been critical in keeping the data flowing even there might be
> > problems at one or two of the sites feeding into the IDD.  With the
> > SSEC machines being out, there are only two sites feeding NOAAPort-derived
> > datastreams into the IDD: us (via our two NOAAPort ingest machines) and
> > LSU/SRCC, so the redundancy has deceased by a third.
> >
> > Cheers,
> >
> > Tom
> > --
> > ****************************************************************************
> > Unidata User Support                                    UCAR Unidata Program
> > (303) 497-8642                                                 P.O. Box 3000
> > address@hidden                                   Boulder, CO 80307
> > ----------------------------------------------------------------------------
> > Unidata HomePage                       http://www.unidata.ucar.edu
> > ****************************************************************************
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: KUD-512290
> > Department: Support IDD
> > Priority: Normal
> > Status: Closed
> >
> 
> 
> 

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: KUD-512290
Department: Support IDD
Priority: Normal
Status: Closed

Attachment: UCAR_NOAAPort_CN_20160428.png
Description: PNG image

Attachment: LSUSRCC_NOAAPort_CN_20160428.png
Description: PNG image


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