FAQ
Coaxial Cable, BNC Connectors and CCTV Tester Q&A
Practical answers on coaxial HD installation: cable length and gauge, solder-free versus soldered BNC connectors, converter cascading and loop-out, tester steps, and HDMI-to-coax bands.
FAQ
FAQ
Site Fault Q&A: No Picture, Jitter, Night Washout, Lost Channels
Troubleshooting by observed symptom: one channel with no picture, rolling borders, night-time washout, close-range white-out, a missing DVR channel and a USB image that stalls.
Standards & Protocols
PAL vs NTSC: TV System Differences and Band Naming
What separates PAL from NTSC in field frequency and frame rate, general mains habits by region, and the naming, pixel counts and bandwidth conversions of 720P, 960H, 1080P and higher bands.
Standards & Protocols
ONVIF and RTSP Interoperability and Integration Order
Protocols and stream addresses as labelled on cameras, encoders and control keyboards, with a check order for cross-vendor work, quantified acceptance figures and fault isolation.
Technical Notes
Dual-Spectrum Thermal and Visible Camera Use Limits
Starting from the detector specification and stated measurement accuracy of dual-spectrum thermal cameras: where thermal and visible channels apply, plus mounting, passage distance and interlocks.
Technical Notes
PoE vs DC 12V Supply: Voltage Drop, Length, Headroom
A loop voltage-drop formula for centralised DC 12 V supply, a far-end voltage table by conductor gauge and length, the boundary between PoE 802.3af and at, and how to size power margin.
Technical Notes
Miniature Camera Focal Length vs Viewing Distance
Convert rated angles and sensor size into coverage width and pixel density for each focal length, with lens thresholds for pinhole cameras in kiosks, cabinets and indoor points.
Selection Guides
USB UVC Camera Selection: Format, Angle and Microphone
For conferencing, remote teaching and recording builds: how USB camera formats relate to bus bandwidth, how to choose lens angle and audio capture, and which capture card fits.
Selection Guides
Retrofitting Old Coax Runs: Keep the Cable, Add an Encoder
For projects with existing coaxial wiring and ageing DVRs: front-end swap only, coaxial-to-IP encoders, or a parallel converter, with hardware parameters, work order and network planning.
Selection Guides
Coaxial HD vs Network Camera: Selection Criteria on Site
Field criteria for coaxial HD and network cameras across cabling, resolution bands, power supply and recorder, plus the converter models that bridge both systems.