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[LDM #LJY-425624]: NEXRAD Level II Feed

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  • Subject: [LDM #LJY-425624]: NEXRAD Level II Feed
  • Date: Wed, 04 Jun 2008 09:13:23 -0600
Alan,

> Well, take a look at this example.  KSFX with a time stamp of 20080530
> 050207.  The size on my local server is 1,420,067 and the size from the
> Boulder is 1,428,651.  Just so happens I keep a log of the sequences,
> and they look identical and they are not out of sequence.  Except for
> the local time difference, the arrival times almost match.  All 69
> radial files are accounted for on both servers.  Unfortunately I don't
> keep the size of the radial file, that might be something I add.  So,
> this could point to the decode software or the files that came from my
> upstream are truncated.  Again, I have no errors on either system that
> the decode software failed.

Please forgive me, but as expert as I am in the LDM, I'm not adept in
the data that it actually transmits.

My understanding is that a single horizontal sweep of a NEXRAD2 
radar is transmitted as four LDM data-products: three of 100 radials
and one of 60 or 65 radials (which is transmitted last and has a 
"/E" suffix in the product-identifier).  Please correct me if I'm
wrong.

If I'm right, then what is the relationship between those LDM data-
products and the entries in your listings?  Is each entry written by
an LDM decoder process that accumulates the four LDM data-products
of each radar sweep into one?  And why does only the last entry have
an "E"?  Or do the entries comprise a single but multi-parameter 
horizontal sweep?

> If I might ask, do you use the Harry Edmond software to decode?

Sadly, I don't know.  I'll ask.  I'll also see if I can get
someone with more knowledge about the data to join this thread.

> Local sequence:
> KSFX 0541 50 20080530050207 01:05:23
> KSFX 0541 51 20080530050207 01:05:27
> KSFX 0541 52 20080530050207 01:05:31
> KSFX 0541 53 20080530050207 01:05:33
> KSFX 0541 54 20080530050207 01:05:37
> KSFX 0541 55 20080530050207 01:05:41
> KSFX 0541 56 20080530050207 01:05:44
> KSFX 0541 57 20080530050207 01:05:46
> KSFX 0541 58 20080530050207 01:05:52
> KSFX 0541 59 20080530050207 01:05:55
> KSFX 0541 60 20080530050207 01:05:59
> KSFX 0541 61 20080530050207 01:06:01
> KSFX 0541 62 20080530050207 01:06:06
> KSFX 0541 63 20080530050207 01:06:09
> KSFX 0541 64 20080530050207 01:06:15
> KSFX 0541 65 20080530050207 01:06:15
> KSFX 0541 66 20080530050207 01:06:19
> KSFX 0541 67 20080530050207 01:06:23
> KSFX 0541 68 20080530050207 01:06:27
> KSFX 0541 69 20080530050207 01:06:36 E
> 
> 
> 
> Boulder sequence:
> KSFX 0541 50 20080530050207 23:05:23
> KSFX 0541 51 20080530050207 23:05:27
> KSFX 0541 52 20080530050207 23:05:31
> KSFX 0541 53 20080530050207 23:05:33
> KSFX 0541 54 20080530050207 23:05:37
> KSFX 0541 55 20080530050207 23:05:41
> KSFX 0541 56 20080530050207 23:05:44
> KSFX 0541 57 20080530050207 23:05:46
> KSFX 0541 58 20080530050207 23:05:51
> KSFX 0541 59 20080530050207 23:05:54
> KSFX 0541 60 20080530050207 23:05:58
> KSFX 0541 61 20080530050207 23:06:02
> KSFX 0541 62 20080530050207 23:06:06
> KSFX 0541 63 20080530050207 23:06:09
> KSFX 0541 64 20080530050207 23:06:13
> KSFX 0541 65 20080530050207 23:06:14
> KSFX 0541 66 20080530050207 23:06:20
> KSFX 0541 67 20080530050207 23:06:24
> KSFX 0541 68 20080530050207 23:06:27
> KSFX 0541 69 20080530050207 23:06:35 E

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: LJY-425624
Department: Support LDM
Priority: Normal
Status: On Hold