When sending and receiving T.140 subtitles, both parties who need to join support T.140 subtitles.

In video conferencing, the empty field noise is required not to be greater than ( )dB. (Fill in the blanks)

Which one is wrong with the description of the VP9660 single board LEDs below?

The switch port connected to the MCU must be: LOOM half-duplex. ( )

Enabling SEC, the system can automatically adjust the network transmission and different error corrections of AV processing for the rich QOS mode of the IP network After enabling SEC, the anti- packet loss ability has been greatly improved ()