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

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3. DTV Signal Information
DTV Signal Information
Digital TV Transmissions
In addition to receiving the current channel 2-69 NTSC format TV stations and channel 01-125 cable stations,
these TV sets contain an extra tuner to receive off-the-air channel 01-99 Digital stations in the ATSC format. DTV
channels 01-99 are mostly in the UHF band because the channel 2-13 VHF band is currently occupied with
analog NTSC stations.
During this transition period as the USA and Canada move from the current analog NTSC format to the digital
ATSC format, transmitting stations will be sending out both formats on two different channels. Some of the
current DTV transmissions are of low power to lower their operating costs of a second transmitter and the pro-
gramming is duplicated with sporadic HDTV transmissions. By now (2001), all major networks have DTV trans-
missions in the larger cities.
Signal Contents
You can determine the noise level and contents of the DTV signal being received by going to the service mode
and examining the transmitted PSIP information received by the TV’s decoder:
1. Enter the service mode: Using the remote control, press buttons: Display, 5, , Power On.
2. Select an active DTV station using the channel up/down buttons.
3. Use the 2 (up) or 5 (down) buttons to locate category DTV.
The WSL indicates signal strength like AGC. 0 = strong and 255 = snow.
4. Use the 3 or 6 buttons to change the data from 0 to 1.
5. Information about the received channel (similar to Figure 3-1) will be added to the screen from the Q box.
Figure 3-1
DTV Signal
Information
Contents of the DTV Signal
The Decoder Status page as pictured in Figure 3-1 reveals that:
•
The DTV received channel is UHF channel (Phy Ch) 56, but the channel number displayed on the TV screen
is (Act) 2.1.
•
The digital video decoding is (Fmt) MPEG2 and the audio decoding is (Fmt) AC-3.
•
Closed caption (CC) levels 1and 2 are being sent
•
The transmitted resolution is (Video Src) 1080i in the 16:9 aspect ratio.
•
Although the audio decoding requested is AC-3, a 6-channel system, there are only two front channels en-
coded and no (0) rear channels sent (Audio Src: 2 / 0 LR).
DTV 0 0
Info
WSL = 0