First reason:
PAT-556 av sender support two group audio video signal input at transmitter end, means you can connect both DVD player and TV Box with transmitter and select the av signal input at receiver end, there is AV 1 and AV 2 as AV input.
Second reason:
PAT-556 support two group frequency band, the commonly use 38khz frequency is F1, and the other only is 56KHz frequency is F2, two group IR frequency could perfect avoid IR interference with the other device with IR Remote control.
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Third reason:
PAT-556 support one transmitter and many receivers, if there is interference at receiver end, then you can change the channels at one of receiver end, the transmitter and the other receiver will change channels at time same times by automatically.
Parts of PAT-556
Transmitter*1pcs
Receiver*1pcs
AV cable*3pcs
IR cable*1pcs
User manual*1pcs
Article from: Smart AV Sender PAT-556
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