Wegener Communications 6420 user manual Live Audio play, LNB DC output, Transport Demux

iPump 6420 User’s Manual

11.Delete Preset Table entry

12.Select tuning by Preset Table entry

LNB DC output

To simplify site setup, the i6420 features an LNB DC output source fed outward on the RF Input center conductor. This powers the electronics in the LNB on the satellite antenna. It is protected against shorted loads with an over-current thermal fuse.

The user controls are:

1. LNB DC ON/OFF

Transport Demux

The incoming Transport stream from the tuner (or alternately, ASI-input card) is de- multiplexed in a software module. This module recovers the Program Allocation Table (PAT), and for each of the Programs listed, a Program Map Table (PMT). It also recovers the PID assigned to COMPEL, as well as all the PIDs assigned for MPE/IP channels. Using the Tables (see Section 3.2.2), the unit controller then identifies the PIDs bearing the live audio streams, and those are passed to decompression stages assigned to the appropriate audio Port.

Key indicators are:

1.No PAT fault indication

2.No PMT fault indication

3.2.2.Live Audio play

Live audio decode and playout from the satellite signal is the most important single unit function. There are three audio ports in the iPump6420, with each assigned multiple “MPEG decoders” (see Figure 1-3in Section 1.3). However, the user is cautioned to be careful here: In most of the user control interfaces, and in other i6420 literature, each port itself is called a “Decoder”.

With this caution in mind, the operation of each of the Audio Decoders (ports) may be described.

Audio Stream Selection

For each Audio Decoder, the Compel or local user may select an audio PES stream, from the Transport, to decode and output. The selection is by Program, and then, within that Program, an audio Language Descriptor. Using the PSI Tables, the unit software identifies the PID bearing the audio PES stream. This is then passed to the correct Audio Decoder (or Decoders, since the same live audio may be played on multiple outputs). Where simple audio stream switches are requested, the command is executed immediately, but the old audio signal runs on until the audio buffer is cleared, and then the new audio signal appears in the output (see Audio Buffer delay, following).

Key indicators are:

1.SERVICES LED on during live audio playout on any Decoder

2.“No Audio found” fault indication

The user controls, for each Audio Decoder (Port) are:

1.Program number (select OFF, follow-tune, Program number, or use the first available in the PAT

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