Re: [ldm-users] NEXRAD3 Again ... part III

On Sun, 31 Jul 2011, Gilbert Sebenste wrote:
>
> On Sun, 31 Jul 2011, Jeff Lake wrote:
>
> > This is getting crazy ...
> > when they switch uplink sites tomorrow maybe that is the problem
>
> Seems like they do that at least a few times a week...I just noticed yesterday
> there was quite a signal drop for about 30 minutes around 2Z;
> I didn't catch whether or not that happened at other times yesterday.
>

I'm seeing many, many cases of retransmitted products that have different
MD5 signatures.  (When our ingest software (which is custom-built) sees a
retransmitted product, it will keep it only if it hasn't already been
received OR if the signatures differ.  I am ignorant of how the ingest
software works at other sites.)

I have seen this sporadically since July 3rd.  This latest spurt started
around 18Z on July 28th.  Unfortunately, I haven't been keeping close
tabs on which uplink site is in use when this happens.  I suspect that
there is a direct correlation.

Later this evening I'm going to dig out a pair of products (the original
and the retransmitted versions) to see just what is different about them.

I find it strange that there are so many retransmits to begin with.  It
makes one wonder if there is an NWS site somewhere that is having
particularly bad reception problems.

  - Bryan