Sony KD-34XBR2 - 34" Hdtv Fd Trinitron Wega, Руководство по обучению

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3. DTV Signal Information
Signal Quality
You can also determine the quality of the received signal while still in the service mode. If the digital signal is
correct, the decoder will process the information and output audio and video in sync. If there are sunspots, rain,
or airplanes for example that can distort the signal the decoder will take longer to try to resolve the errors.
Therefore, the time the signal enters and leaves the decoder will be longer. This delay identifies digital reception
errors.
You can see the audio and video processing time in the service mode. From the service mode, select category
DTV. Use the remote’s number 3 button to change the data from 1 to 3.
The following audio and video data packet processing example shown in Figure 3-2 shows the packet number
going into the TV’s decoder (PTS) and what packet has been successfully processed (PCR). At the right is the
decoder processing time is given in ms. The greater the difference in packet number or processing time in ms,
the poorer the signal quality (since the decoder takes longer to try to resolve digital errors). A large number of
digital errors may be due to sunspots, airplanes, storms or transmission errors. The picture shown in Figure 3-2
is of a good quality signal.
Figure 3-2
Input/Output
Packet data