Two ways to build a DIY security camera system. The parts are different.
Pick the kind of cameras you are putting in. The parts are different.
IP cameras (PoE) — one Cat 6 cable powers the camera and carries the video. Needs an NVR.
AHD cameras (coax) — video on coax, 12V power on a second lead. Needs a DVR.
Not sure which one? Read PoE vs AHD.
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