| Modern TVs (anything that doesn’t have an analogue-only path all the way to the display, which is probably almost every TV sold in the last 10-15 years) are designed in a way that (unintentionally) disregards the importance of predictable signal-to-visibility delays. Basically this is because all modern displays have a digital path from their (primarily digital) inputs which always (even if it’s “disabled”) includes signal processing to convert the incoming signal (of varying resolutions, refresh rates, color spaces, etc.) to signal(s) which can be sent to the LCD (either through the TCON embedded in the side of the LCD or through some custom ASIC that directly generates the analogue waveforms to drive the matrix of Liquid Crystals), backlight driver(s) (because artificially-measured contrast ratio numbers can be seriously enhanced for marketing), audio outputs, etc. That’s on top of the extra image processing features that many TV’s advertise (“smooth motion”, “200hz”, etc.) which generally require the video DSP to buffer one or more frames to perform the processing (and maybe generate intermediate frames). These additional features can often be disabled by enabling a “gaming mode” which is (usually) designed to reduce perceptible input latency but this is not always implemented correctly by the manufacture and most reviewers don’t perform end-to-end latency measurements so there’s not much incentive for manufacturers to do much better than “ok”. Analogue-only CRT TVs didn’t have nearly the same complexity (or features) in their signal processing and could reliably be trusted to display a given input with a minimal delay, mostly due to the fact that they didn’t have any (significant) form of memory to buffer signals for processing. If I recall correctly, there was an era in analogue broadcast where the signal that was generated in the studio broadcast camera became the synchronisation signal for every TV that was tuned to that channel which essentially means that a TV tuned into that broadcast would actually scan the electron beam across the CRT at exactly the same rate and time as all the other TVs on the same channel. This required careful signal design to ensure that a “cheap” TV with poor timekeeping could still synchronise its operation with the incoming signal but it was far more practical/affordable than trying to buffer an entire frame given the technology at the time. To answer your question directly, it might allow you to have synchronised broadcast to multiple TV’s but it may require playing with the output resolution/refresh rates of your OpenHD receiver and with the settings on the TV (try looking for a “gaming” picture preset). |