[EAS] Mindless Murmurings about Munged Messages

[David Turnmire]

On 8/8/2012 2:49 PM, ray at electronicstheory.com wrote:
> ... I do NOT recall ever seeing what I am now seeing with the DASDECs.
>
> The DASDEC sometimes doesn't catch the whole message.  I'm fairly certain that
> this is due to atmospherics during storms.  When it gets a partial message - it
> logs it as a partial message.  I don't recall ever seeing that with the other
> systems.
> ...
Are you sure it is REALLY a partial message?  I came from a SAGE 
background when we switched to DASDECs.  And I ran into an oddity that 
may be what you are observing.  I don't have my DASDEC in front of me 
right now, so I'm going from memory.  As I recall, if you are on the 
Decoder menu and observing the log of alerts, the associated links play 
essentially only the voice part of the message.  But... if you go to the 
Setup=>Audio page and click on the "snap shot" links, you'll get a more 
complete recording, including any program audio leading into and out of 
the alert, the data tones, etc.

Now here comes the oddity... when you click on the snapshot links, the 
recording may start in the middle of the alert... but if you are patient 
and play the recording to the end, you'll hear the beginning of the 
alert... later, at the end of the recording!.  Essentially what is 
happening is the DASDEC records a continuous loop of something like 3 
minute duration.  When the snapshot is triggered (typically be an 
alert), it essentially captures that loop as it exists at that time.  
But where the alert is within that loop is somewhat random.  Apparently 
doing it this way made it easier for the programmers... but more 
confusing and less convenient for the users. I put a request in for them 
to change that and they said they are considering it.

Take a closer listen to what you have on your machines and see if this 
is what you are experiencing.  I have had mine in service since 
something like November and since I'm SECC chair, I tend to monitor more 
sources than the typical station (four CAP servers and four receivers).  
Plus we have a couple DASDECs at other locations in the state that I 
routinely login to to see what is happening in those markets.  I haven't 
run into the "partial message" issue, other than what is described above.

Dave