Troubleshooting Analogue and HD-over-Coax Cameras

Analogue and HD-over-coax systems fail in patterns. Once you have seen the patterns, fault-finding becomes a five-minute exercise instead of a half-day on a stepladder. This short module covers the two essential test tools every installer should carry, and the systematic procedure for diagnosing the most common faults — rolling lines, no picture, intermittent dropouts, ground loops, and protocol mismatches.

What this module covers

The lessons cover the two main test tools used on UK sites — a CCTV test monitor (Aceview, BNC Pro or similar) for verifying the camera at the camera end, and a multimeter for cable continuity and voltage drop checks — and a structured fault-finding flow that starts at the camera, moves to the cable, and ends at the recorder. The most common faults are demonstrated with real symptoms: ground-loop hum on a long shotgun cable, HD-TVI vs HD-CVI mismatch on a hybrid recorder, and voltage drop on a 24V camera fed from a 12V PSU.

Who it is for

Installers who have just lost three hours on a no-picture call, electricians retrofitting CCTV onto existing coax of unknown quality, and apprentices starting to take their own troubleshooting calls.

Why it matters

The customer does not care that the recorder works fine when you take it back to the office. They care that their forecourt camera shows a black screen at the time of an incident. The fault-finding procedure in this module gets you to the actual cause — usually one of three things — in the time it takes to climb the ladder. It also gives you the evidence you need to justify a callback charge if the cause turns out to be the customer’s coax, not your equipment.

Lessons in this module

Lessons:

2 Main Tools for Analogue & HD troubleshooting
Troubleshooting of Analogue & HD Cameras

This module is also available as a part of a comprehensive CCTV Installation Course for £149.