TANDBERG E5780, Справочное руководство

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Preventive Maintenance and Fault-finding
Page 6-12 Reference Guide: evolution 5000 E5780 and E5782 Encoder
ST.RE.E10135.4
6.7.5 Video Fault-finding
Fault Symptoms
Table 6.2: Video Fault-finding
Problem What to do
Video input lock error Check video input.
Video - wrong line standard Check which video format is selected.
VCM stopped Reboot.
Bad parameters Check set-up.
Breaks in Transmission
If a transitory break in transmission occurs then check the encoding mode option of the
Encoder (see
Chapter 4, Operating the Equipment Locally ).
In the standard delay, low delay, very low delay and mega low delay the following are not
seamless: encoding modes, bitrate and GOP changes. This is because the Encoder tries to
maintain minimal end-to-end delay (latency) and that means buffer sizes must be as small as
possible. In the standard delay, low delay, very low delay and mega low delay encoding
modes the buffer size is selected by the video bitrate. Changing the bitrate changes the buffer
size, requiring a reset of the coding process.
For reflex operation video bitrate changes must be seamless as the bitrate varies
continuously. All the seamless modes are seamless only for video bitrate changes. However,
for some GOP changes operation can be seamless, but this aspect is not guaranteed.
Noise Reduction
Where incoming picture material is corrupted by high frequency noise (such as white noise) it
is advisable to make use of the noise reduction process. Noise reduction can be selected at
either the front panel or by the MEM.
6.7.6 Audio Fault-finding
If having problems when using the Dolby E Pass-through coding mode then refer to Annex F,
Audio Modes , for information about using this mode.
6.7.7 Mux Fault-finding
If there is no output from the ASI connectors, check the following:
1. The bitrate - if it is too low then the video etc. is automatically switched off.
2. The packet length - should be 188 or 204 bytes depending upon configuration.