[ppppenguin]

SDI and HD-SDI only specify 15dB return loss across the bandwidth but running without a termination will often cause them to fail completely. It's rare to have looping inputs and separate terminations with SDI so the problem doesn't usually arise.

When you come from a traditional professional broadcast environment correct termination isn't even something you think about. You just do it right. I've certainly heard horror stories concerning younger broadcast technicians who have absolutely no idea about how to connect analogue video correctly. One good one was a string of monitors with looping inputs. The tech connected one end of the line to an output of the distribution amplifier. And the other end of the line to another output of the same VDA! Some of the monitors seemed OK, others were mysteriously in monochrome. My friend who was on set told me it took him a while to work out what had happened.