Jeff,
Max hits the mark pretty well. The reason you are getting upconverter alarms in th SEM may be due to the fact that the program I.D. (PID) is incorrect. If the Sem has no forward error correction (FEC) available in the stream you have programmed it to look at, it cannot produce a Qam.
Sorry I didn't think of this earlier.
A SEM can operate in an ASI de-multiplexing mode, which I think Max was refering to, but I don't think thats what you are looking to do in your particular application. ASI demux in the SEM is, and correct me if I'm wrong here, Max, is intended to provide an ASI output stream, and will not simultaneously produce a Qam output stream. Either or, but not both.
What you want to do here, if I'm correct, is mux one or more ASI supplied HD streams in a 6 meg channel. To use a SEM for this the following must apply, and 'Splicer' should note:
When using the SEM in "Manual Routing' you are essentially directing it to produce an ATSC (Digital or Qam) signal which you are supplying to it via an ASI input. ( Recall the Input-Output configuration window in the Graphical Interface window (GUI), also known as the SEM-EM.)
The SEM only 'sees' what you input it to look for. (i.e. program 3 on ASI input 4) It will output it on any stream you direct it to. (i.e. Qam 1A on your routing table). If you input the correct PID for the program, then you will see "Successful-Remultiplexing" on the Output Utilization? of the "Show status" window of the EM.
If you see the error indicating a "Missing PAT" then the input PID is incorrect or the stream is simply not there. This causes an error in the SEM because there is no FEC available, and the Upconverter you are trying to assign it to will fault. This causes the alarm you are seeing, I'm almost sure of it.
As for your choice of Demodulators (DDM 800?), How many ASI outputs does it have, and most importantly, does it allow "restamping" of the PID's? Here's why...
The SEM, in Manual Routing, would be unable to determine which program (via PID) you want to transport to on an output stream if you are inputing simultaneously more than one stream to the input ASI port, if these input streams bear identical Program ID's.
If you are inputing two seperate streams, each bearing the same PID (Program ID), the SEM will fault. It just doesn't have the ability to tell the difference between Wxxx's Program 3 and Wtrd's Program 3. If they are in the same ASI input stream on the backplane, the SEM will fault. This will also produce your Upconverter fault as the SEM will have no FEC.
Joe 50: Great reference suggestion. Try supplying some answers once in a while. They already have the manuals. What they need is help, not a handshake..........
Re: Adding HD to a system Question
Member #: 1596
Registered: 1996-2001
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Name:
Bruce Chilsted
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