@BlueSci
This is analogue rather than digital signalling, so there's no definitive answer: aspects such as bearer gauge and jointing become significant to total impedance. In typical domestic circumstances there shouldn't be any effective limit as long as the cable is of adequate quality: without other external factors in play many hundreds of metres should be possible over any reasonable bearer.
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Sky Glass 55" (on ethernet) & two Stream Pucks (one ethernet / one WiFi)
BT Halo 3+ Ultrafast FTTP (500Mbs), BT Smart Hub 2
