On Wed, 16 Jun 2010, Unidata User Support wrote:
Hi Gilbert, et. al.,
This a quick note to clarify something that Gilbert said in his
email earlier today.
What Gilbert was not aware of was we were working on the configuration
of noaaport.unidata.ucar.edu (aka desi.unidata.ucar.edu), so the
dropouts seen in its NEXRAD3 volume plot were/are not a result of
low/bad signal, but, rather, of our upgrade work.
OK, that's good to know.
As to reception quality on our NOAAPort ingest machines, here is a S75_TEST
listing from one of our ingest machines:
Device Firmware Ver 3, Rev. 1 --- RF Firmware Codes 0x506
--------------------------------------------------------------------------
Symbol Rate 6.349000 Msps Frequency 1193.500000
The viterbi Bit Error Rate is 0.0000e+00 Viterbi Rate 7
LNB Power On, Polarization = 1, Band = 1
Signal Strength: 73, Signal Lock: 1, Data Lock: 1, Uncorrectables: 0
The indicated signal strength (73), locked frequency (1193.5) and
viterbi Bit Error Rate (0.0000e+00) have not changed on this machine in
the past 3 days. We may be lucky that the changes to broadcast signal
strength have not effected our ingest quality.
Interesting. Some time ago, when you showed me your stats, you had a
signal strength of around 80. You saw the same recent drop in signal I
had. Currently, my signal strength is at 77, and that's stronger than
yours. It should be the other way around, because:
1. You have a 3.8 meter dish, I have a 3.7 meter dish with a snow cover on
2. You are theoretically in a stronger signal area per the SES-1 signal
map graph
Either way, though, here's something to consider. Jose Nieves has
software he wrote called npstats that shows reception in real time.
See:
http://www.opennoaaport.net:8025/ (From Puerto Rico)
And
http://noaaport.admin.niu.edu:8025/ (From 60 miles west of Chicago)
It works with a kludge on 64 bit systems, but with 32 bit systems it works
out of the box. rpm -ivh the RPM, as root, type service npstatsd start,
and you are live (takes about 5 minutes to start graphing).
With the S75, it graphs Eb/n0; With the S75+, it graphs signal strength.
Unfortunately, EbN0 is somewhat more useful, but the S75+ doesn't
have the capability to send out that information.
at 20Z, so my charts are a little puny right now.
http://www.noaaport.net/software/packages/npstats-0.5.p1.14/packages/
I think you also need his novramon software installed to get it to work,
I'm not sure. If so...
http://www.noaaport.net/software/packages/novramon-2.0.p1.3/packages/
I have both, and are very helpful in determining when I have reception
issues.
Any chance UNIDATA could look into installing this? Since you have an S75,
we would see your Eb/N0 data, and between all 3 of us, be able to easily
tell when an issue is occurring.
*******************************************************************************
Gilbert Sebenste ********
(My opinions only!) ******
Staff Meteorologist, Northern Illinois University ****
E-mail: sebenste@xxxxxxxxxxxxxxxxxxxxx ***
web: http://weather.admin.niu.edu **
*******************************************************************************
