Forum Discussion

MikeyD3's avatar
MikeyD3
Tuning in
6 months ago

HD/UHD Signal

Hi, I've been a fibre optic customer ever since Cable & Wireless dug up the pavements decades ago. At that time HD TV didn't exist, hence I was curious whether the junction box, splitter & coaxial leads fitted inside the house way back then actually cope with and pass through HD & UHD signal, or as those components were built before such technology even existed they reduce the signal down to SD and it's in fact the digital upscaling technology within modern TV's which gives the impression of getting 1080P & 4K?

  • nodrogd's avatar
    nodrogd
    6 months ago

    It’s exactly the same system that carried analogue. When terrestrial Freeview & Sky satellite launched digital there was no need to change the cabling or antennas. The same frequencies are used. It is just the equipment at either end (transmission equipment & set top boxes) now deal with broadcast digital data streams & not analogue signals. The difference between SD, HD & UHD is all down to data rates & compression techniques. As far as the cables & splitters are concerned they are doing what they have always done. Pass a radio signal between transmitter (the cable headend) & receiver (your set top box). What that radio signal contains makes no difference.

    Most of my wiring is originally from 1993, when we had 40 analogue cable TV channels & nothing else. It now carries 200+ digital channels in all definitions, plus my 350Mb internet & phone.

  • nodrogd's avatar
    nodrogd
    Very Insightful Person
    6 months ago

    It’s exactly the same system that carried analogue. When terrestrial Freeview & Sky satellite launched digital there was no need to change the cabling or antennas. The same frequencies are used. It is just the equipment at either end (transmission equipment & set top boxes) now deal with broadcast digital data streams & not analogue signals. The difference between SD, HD & UHD is all down to data rates & compression techniques. As far as the cables & splitters are concerned they are doing what they have always done. Pass a radio signal between transmitter (the cable headend) & receiver (your set top box). What that radio signal contains makes no difference.

    Most of my wiring is originally from 1993, when we had 40 analogue cable TV channels & nothing else. It now carries 200+ digital channels in all definitions, plus my 350Mb internet & phone.

    • MikeyD3's avatar
      MikeyD3
      Tuning in
      6 months ago

      Many thanks for that helpful answer. It was just a thought that occurred to me as if upgrade from tivo to 360 or a dvd player to a 4k blue ray player/streamer you need to updrade the hdmi lead to be able to pass thru 4k content, but as you've kindly explained, its the set top box & player which decodes it (the signal) initially. Many thanks & have a great weekend:)

      • nodrogd's avatar
        nodrogd
        Very Insightful Person
        6 months ago
        MikeyD3 wrote:

        Many thanks for that helpful answer. It was just a thought that occurred to me as if upgrade from tivo to 360 or a dvd player to a 4k blue ray player/streamer you need to updrade the hdmi lead to be able to pass thru 4k content, but as you've kindly explained, its the set top box & player which decodes it (the signal) initially. Many thanks & have a great weekend:)

        You only mentioned coaxial cables previously. HDMI leads are a different matter. These data leads have had to evolve as the technology has changed. The increase in compression rates & the introduction of content protection means there are several standards out there. The latest standard HDMI 2.0 leads are the only ones compatible with UHD & HDR that is used on modern TVs.

        https://avlab.com.tw/blog/view/43 

         

  • mda99das's avatar
    mda99das
    Up to speed
    6 months ago

    Are you sure you had fibre optic from C&W? In the 90s and 2000s they used siamese coax with a phone cable attached. The nodes I believe were fibreoptic but to the customer's premises they were coax. I had a C&W install back in 1995 and still have that cable buried in the garden somewhere.  I think there a loads of new cabinets a few meters down the road.

    • MikeyD3's avatar
      MikeyD3
      Tuning in
      6 months ago

      Very interesting, many thanks for all the replies. My C&W install was in 1993 & I vividly remember the salespersons patter about the amazing fibre optic technology & its benefits over satelite dishes etc, hence I just assumed the whole cable journey was fibre optic. I definitely have the asymetrical type cable hence it will be the thicker coax attached to the thinner phone line via HFC. When posting my query I had wondered if there might be any benefit in buying new coax leads for inside the house from junction box to the UHD VM box & router (like we get new hdmi leads with newer higher resolution equipment), hence now that I've been educated about coax's capabilites & signal decoding I shan't be making that unnecessary purchase 🙂

      • nodrogd's avatar
        nodrogd
        Very Insightful Person
        6 months ago
        MikeyD3 wrote:

        When posting my query I had wondered if there might be any benefit in buying new coax leads for inside the house from junction box to the UHD VM box & router (like we get new hdmi leads with newer higher resolution equipment), hence now that I've been educated about coax's capabilites & signal decoding I shan't be making that unnecessary purchase 🙂

        You should not mess with VMs coaxial cabling anyway. VM use specialised triple screened cabling. This is because the RF spectrum they use is also used by Terrestrial Freeview TV, DAB digital radio services & more recently 4G/5G mobile phone networks outside of the cabling. Any ingress from these sources can seriously disrupt your services, & if it reaches the street amplifier the entire local network can be compromised affecting other customers as well.

  • Roger_Gooner's avatar
    Roger_Gooner
    Alessandro Volta
    6 months ago

    Do not consider coaxial cable as seriously inferior to, say, copper phone wire, and a lot of the cable plant is over 30 years old. Under ideal conditions I'd expect a short coaxial drop cable to handle 3Gbps. The HFC network easily supports 1Gbps and the V6, 360 (and Stream) boxes all support UHD and HDR which VM broadcasts from its central headend. For SD and HD broadcasts the upscaling is done either by the boxes or the TV and so has nothing to do with the coaxial cables.