How to Troubleshoot No Video Output or Abnormal Images After Installing a Video Optical Multiplexer?

After a video optical multiplexer is installed, if there is no video output or the images are abnormal, follow this general troubleshooting sequence: first, confirm that the transmitter and receiver are used as a pair and that the direction is not reversed; second, use an optical power meter to check the received optical power against the receiver sensitivity, and check whether the patch cord end faces and the FC connectors are clean and whether the optical fiber is kinked or damaged; third, check the cable connection and the quality of the BNC connectors on the 75 Ω coaxial video cable, and verify that the camera output format matches that of the back-end display device; fourth, confirm that the power supply (AC220V or DC-48V) is normal and that the data and audio wiring sequence is correct. For routine maintenance, switch off the power before inserting or removing the optical port, clean the end faces regularly and re-measure the optical power. If the fault persists, contact the manufacturer's technical support.