Default signal is HD AHD. If you are using other DVR, you need to switch to other signal firstly. UP:AHD Down:CVI Left:TVI Right:CVBS. Video Output: HD-AHD (1080p), (AHD, TVI, CVI, CVBS). Default signal is HD AHD, How to shift AHD/CVI/TVI/CVBS Signal by OSD?.
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