HDCVI Series DVR User’s Manual913.5.2 Connecting Video OutputVideo output includes a BNC(PAL/NTSC1.0VP-P ,75Ω)output ,a VGA output and HDMI output. Systemsupports BNC, VGA and HDMI output at the same time.When you are using pc-type monitor to replace the monitor, please pay attention to the following points: To defer aging, do not allow the pc monitor to run for a long time. Regular demagnetization will keep device maintain proper status. Keep it away from strong electromagnetic interference devices.Using TV as video output device is not a reliable substitution method. You also need to reduce theworking hour and control the interference from power supply and other devices. The low quality TV mayresult in device damage.3.6 Connecting Audio Input & Output, Bidirectional Audio3.6.1 Audio InputThese series products audio input port adopt BNC port.Due to high impedance of audio input, please use active sound pick-up.Audio transmission is similar to video transmission. Try to avoid interference, dry joint, loose contact andit shall be away from high tension current.3.6.2 Audio OutputThe audio output signal parameter is usually over 200mv 1KΩ (BNC or RCA). It can directly connect tolow impedance earphone, active sound box or amplifier-drive audio output device.If the sound box and the pick-up cannot be separated spatially, it is easy to arouse squeaking. In thiscase you can adopt the following measures: Use better sound pick-up with better directing property. Reduce the volume of the sound box. Using more sound-absorbing materials in decoration can reduce voice echo and improve acousticsenvironment. Adjust the layout to reduce happening of the squeaking.3.7 Alarm Input and Output ConnectionPlease read the followings before connecting.1. Alarm inputa. Please make sure alarm input mode is grounding alarm input.b. Grounding signal is needed for alarm input.c. Alarm input needs the low level voltage signal.d. Alarm input mode can be either NC (normal Open) or NO (Normal Close)e. When you are connecting two DVRs or you are connecting one DVR and one other device, pleaseuse a relay to separate them,2. Alarm output