You do not need a degree. You do need to know what plugs into what, why power matters, and how to explain it to a normal person.
Here is the short version of what we sell and install every day.
IP CCTV vs AHD
IP cameras talk over network cable (usually Cat5e/Cat6 with RJ45). They land on an NVR (network video recorder) and often get power from PoE (power over Ethernet) — one cable for data and power.
AHD is analog HD over coax (BNC connectors) into a DVR, with separate DC power on most cameras.
Connectors & wire
RJ45 goes on Cat5e/Cat6 for IP cameras, switches, and NVRs.
BNC goes on coax for AHD video.
DC barrel (or screw terminal) is camera/power supply DC.
HDMI is monitor out. Do not mix them — wrong connector = no picture, no power, or a melted mood.
AC vs DC voltage
AC (alternating current) is wall power — it flips direction many times a second.
DC (direct current) flows one way — that is what most cameras, NVRs, and Ajax hubs want from a power supply.
Plug AC into a DC-only device and you toast gear. Always match voltage, polarity, and AC/DC on the label.
PoE, networking & polarity
PoE switches/injectors send DC power down the Ethernet pairs so IP cameras do not need a brick at the camera.
Learn basic IP addressing, uplink vs camera ports, and cable length limits.
On DC barrel and screw terminals, polarity matters — reverse it and nothing works (or something smells weird).
Access, intercom & Ajax
We sell Akuvox-style access/intercom (doors, readers, indoor stations) and Ajax wireless smart alarms (hub, detectors, sirens, app).
Installers need clean cable routes, solid mounts, and patient customer walkthroughs — not jargon.
Ohm basics & TEK install
Resistance (ohms) rises with thin/long wire — voltage drop makes cameras brown out at the far end.
Use the right gauge and keep power runs sane. TEK install is Greater Cincinnati first; travel jobs get quoted separately.