SDI signal transmission through a camera post fails despite voltage passing through

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2015Center Post forum

A 50 ohm cable cannot reliably carry HD-SDI signals; 75 ohm cable is required for proper HD-SDI transmission.
Non-HD-SDI rated cables may work temporarily over short distances but become unreliable as the cable and connections age or degrade.
It is possible for a cable to successfully carry voltage while failing to transmit SDI video signal, indicating an impedance mismatch rather than a simple wiring break.
Beldin 179DT is a suitable thin cable option for HD-SDI applications.

The original setup had worked previously, suggesting the cable degradation theory is plausible but the initial failure mode remains unexplained.
The user was not familiar with electrical principles, so the technical explanation may not have been fully verified by them.
No conclusive resolution was documented; the user planned to run a separate standard SDI cable instead of fixing the original post cabling.