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    #31
    Originally posted by steelersman View Post
    I don't understand all of this hype about the big switch? Won't this only affect people that don't subscribe to any cable or satellite? I would imagine that most people in this day and age have some sort of cable or satellite that they subscribe to and they won't be affected.
    Yes. but... not everyone installs a cable box at every tv location, but they soon will. And of course be charged accordingly. Not going to be fun for people with 10 TV's and 1 set top box for the one HD tv in the house.
    "Electricity is actually made up of extremely tiny particles called electrons, that you cannot see with the naked eye unless you have been drinking."

    Comment


      #32
      Originally posted by hbiss View Post
      Grich, egnlsn, if you dig down in rabbitears.org it looks like when they do they will be greatly reducing their power.
      -Hal
      My first response would be that because of signal propagation, less power is required to transmit a VHF signal the same distance than a UHF signal.

      Obviously a bit old, but this article also addresses that subject.
      CIAO!

      Ed N.

      Comment


        #33
        Originally posted by stickboy1375 View Post
        Yes. but... not everyone installs a cable box at every tv location, but they soon will. And of course be charged accordingly. Not going to be fun for people with 10 TV's and 1 set top box for the one HD tv in the house.
        The DTV transition of 2/17/2009 affects OTA only. Analog will be around on cable for some time to come. Eventually, most analog will disappear from cable (they will probably keep a dozen or two analog channels), but that will be to free up bandwidth for more HD services, High Speed Internet, etc. It has nothing to do with 2/17/2009.
        CIAO!

        Ed N.

        Comment


          #34
          My first response would be that because of signal propagation, less power is required to transmit a VHF signal the same distance than a UHF signal.

          Looks like they are lowering the power from their old NTSC analog days when they move their digital signal to the old VHF transmitter.

          Drill down: name>station>technical data & Screencaps>FCC query

          -Hal
          Last edited by hbiss; 01-05-09, 12:06 PM.

          Comment


            #35
            Originally posted by hbiss View Post
            My first response would be that because of signal propagation, less power is required to transmit a VHF signal the same distance than a UHF signal.

            Looks like they are lowering the power from their old NTSC analog days when they move their digital signal to the old VHF transmitter.

            Drill down: name>station>technical data & Screencaps>FCC query

            -Hal
            If you then scroll down (within FCC Query) to the top digital listing and click "Application Info," you will see that the expiration date of that particular license is 2/17/2009 (at least for the ones I looked at). I would expect that beginning 2/17 and for the next little while, stations will be playing around with their power to optimize their coverage.

            I'll see what I can find out.
            Last edited by egnlsn; 01-05-09, 12:48 PM.
            CIAO!

            Ed N.

            Comment


              #36
              Originally posted by hbiss View Post
              The Des Moines stations that are analog VHF will go back to their VHF channels for digital after the switch.

              Grich, egnlsn, if you dig down in rabbitears.org it looks like when they do they will be greatly reducing their power.

              Isn't that in keeping with only allowing low power stations to remain in the VHF band?

              -Hal
              From an engineer at a Fox station: "Analog power is based on peak power, digital power is based on average power as well as signal to noise ratio differences of it takes to decode the analog and digital signals. You are comparing apples to oranges. It more than just power levels."

              Compare the coverage areas:

              Channel 7 Analog

              Channel 7 Digital
              Last edited by egnlsn; 01-05-09, 02:00 PM.
              CIAO!

              Ed N.

              Comment


                #37
                Originally posted by egnlsn View Post
                The DTV transition of 2/17/2009 affects OTA only. Analog will be around on cable for some time to come. Eventually, most analog will disappear from cable (they will probably keep a dozen or two analog channels), but that will be to free up bandwidth for more HD services, High Speed Internet, etc. It has nothing to do with 2/17/2009.
                All cable companies are claiming all digital channels. so what gives? I'm just going to wait and see for myself.
                "Electricity is actually made up of extremely tiny particles called electrons, that you cannot see with the naked eye unless you have been drinking."

                Comment


                  #38
                  DirecTV has always been digital, they just convert back to analog for the TV sets to work. That's why your picture pixelates during bad weather, not enough signal if it's not tracked in good. Digital cable does the same thing when it works, they also convert it back to analog. At least satellite's picture comes back after the storm.

                  Comment


                    #39
                    Originally posted by kbsparky View Post
                    For those who have procrastinated in getting their Gov't coupons, here is some bad news:

                    "... U.S. consumers who wait too long to request government coupons to subsidize converter boxes for the digital television transition in February may come up empty-handed, a regulator has warned...."

                    Full story here.
                    Sounds like it may already be too late.
                    http://www.boston.com/business/ticke...nsition_p.html
                    Tim
                    Master Electrician
                    New England
                    Yesterday's Technology at Tomorrow's Prices

                    Comment


                      #40
                      All cable companies are claiming all digital channels.

                      Well, now we are mixing two cans of worms together. There are two separate and unrelated things that some people get confused:

                      1) The Digital Transition of the broadcast or over-the-air TV that you receive with an antenna. This is what we have been discussing in this thread. Nothing to do with cable or satellite.

                      2) The elimination of analog by the cable companies. Even though over-the-air broadcasts are digital the cable companies will convert them to analog, so if you have cable nothing will change.

                      For now.

                      The cable companies want to eliminate those analog channels because they are bandwidth hogs and they are running out of room. They can put up to ten digital channels or three or four HD channels in the same space as one analog channel so the switch to digital is a no brainer. Kinda like compressing your computer HD when it runs out of room.

                      When this happens every TV on cable will either have to have a digital tuner (which all do that have been manufactured in recent years) or a cable box for the TV just to work. A cable box will be required in most cases to get the premium programming, pay-per-view, etc. just like now.

                      Some cable companies have timed their own change to digital to coincide with the Digital Transition. There are lots of theories as to why, some good, some nefarious.

                      -Hal

                      Comment


                        #41
                        Originally posted by hbiss View Post
                        All cable companies are claiming all digital channels.

                        Well, now we are mixing two cans of worms together. There are two separate and unrelated things that some people get confused:

                        1) The Digital Transition of the broadcast or over-the-air TV that you receive with an antenna. This is what we have been discussing in this thread. Nothing to do with cable or satellite.

                        2) The elimination of analog by the cable companies. Even though over-the-air broadcasts are digital the cable companies will convert them to analog, so if you have cable nothing will change.

                        For now.

                        The cable companies want to eliminate those analog channels because they are bandwidth hogs and they are running out of room. They can put up to ten digital channels or three or four HD channels in the same space as one analog channel so the switch to digital is a no brainer. Kinda like compressing your computer HD when it runs out of room.

                        When this happens every TV on cable will either have to have a digital tuner (which all do that have been manufactured in recent years) or a cable box for the TV just to work. A cable box will be required in most cases to get the premium programming, pay-per-view, etc. just like now.

                        Some cable companies have timed their own change to digital to coincide with the Digital Transition. There are lots of theories as to why, some good, some nefarious.

                        -Hal
                        Thanks Hal.
                        "Electricity is actually made up of extremely tiny particles called electrons, that you cannot see with the naked eye unless you have been drinking."

                        Comment


                          #42
                          Originally posted by stickboy1375 View Post
                          All cable companies are claiming all digital channels. so what gives? I'm just going to wait and see for myself.
                          Hal gave an excellent explanation. Let me just add that most large cable companies are doing ADS (Analog Digital Simulcast), which is the duplication of the analog channels in digital format. The settop box has all of the channels below 100 mapped to their digital counterpart, so that when you select channel 2, rather tuning to 54MHz the box tunes to the frequency where the digital transmission of channel 2 is located. Eventually, they will start taking the analog channels off the system, and if you have a box, you will never know it. Most likely, a dozen or 2 analog channels will remain (locals, QVC, stuff like that) for some time.
                          CIAO!

                          Ed N.

                          Comment


                            #43
                            Originally posted by hbiss View Post
                            The Des Moines stations that are analog VHF will go back to their VHF channels for digital after the switch.

                            Grich, egnlsn, if you dig down in rabbitears.org it looks like when they do they will be greatly reducing their power.

                            Isn't that in keeping with only allowing low power stations to remain in the VHF band?

                            -Hal
                            The intent of the FCC was to give stations the same coverage area with digital transmission as they have with analog. Since it takes less power at VHF frequencies to achieve a given coverage area than at UHF frequencies, many stations elected to return to their original VHF channels. The FCC computer models have shown some stations can replicate their analog coverage area with less power transmitting in digital. Let's hope they're right.

                            An extreme example...Channel 5 in Des Moines transmits 100kW analog. They are returning to channel 5 after the transition. Their digital license is calling for only 11.5kW. Since low-band VHF channels (2-6) are more prone to skip and electrical interference, many people are worried that a low-band VHF DTV signal just isn't going to hold up in electrically noisy environments. Most low-band stations are moving to either UHF (14+) or high-band VHF (7-13) for their final DTV channel assignment.

                            I haven't visited rabbitears.org...I may do that tonight.
                            Gregg

                            I'm just here for the pictures!

                            Comment


                              #44
                              The FCC computer models have shown some stations can replicate their analog coverage area with less power transmitting in digital.

                              Ahh. I was wondering how they could cut their ERP from 100Kw to 11.5Kw and the coverage area stayed the same.:rolleyes:

                              I've got a bridge I want to sell you too.

                              -Hal

                              Comment


                                #45
                                Originally posted by hbiss View Post
                                Ahh. I was wondering how they could cut their ERP from 100Kw to 11.5Kw and the coverage area stayed the same.:rolleyes:

                                I've got a bridge I want to sell you too.

                                -Hal
                                I'm glad I don't work for that station. :smile:
                                Gregg

                                I'm just here for the pictures!

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