Rotary Joints for Transmitting HD-SDI Signals Through a Blocked Central Axis

摘要

Transitioning from analog to digital video, and especially to HD-SDI 292M or 424M, is not a simple matter. Normal coaxial cables work with non-rotating applications, but if the system is turning the digital signal has to pass through the rotary joint. For transmitting slower signals, the conventional approaches include the use of gold-on-gold, silver-graphite-on-brass or silver-plated slip rings. The diameter of the overall system is the constraining factor here. They can work at frequencies up to 250 MHz with very small diameters and at up to 100 MHz with larger diameters.