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    HD TV antenna

    We have our boat on a slip near Great Bay in New Hampshire. Our TV reception on the dock has been fair at best at high tide and nonexistent at low. We just installed a Majestic UFO antenna today and it's incredible! We finished running the cable an hour before low tide. Ran the TV channel search and when done we had 14 channels, before at high tide we had 4. If you are looking for free HD TV I would recommend you look in to them!

    #2
    Is it a "stand alone" or is a "box" required? Or was that just with earlier model TV's?

    Dave
    Dave
    Restoring/ upgrading: 1990 Ciera Sunbridge 2655 ST, "One Particular Harbour"
    5.7 Mercruiser Alpha 1 Gen 1 (my floating retirement villa if it doesn't kill me first)
    Sold:
    1995 SeaPro 210 C/C "Hydro-Therapy"
    Mariner 150
    Towing with:
    2002 Ford F 350 7.3L Super Duty
    Near High Rock Lake, N.C.

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      #3
      What were you using before ? I am looking at a Shakespear 3015
      Port: Sassafras River Georgetown, MD Bayliner 2000 2855 7.4

      http://www.chart.state.md.us/video/v...50fa36c4235c0a

      Comment


        #4
        Converter boxes are only needed on older analog TVs. Most stations only transmit a digital signal today. That said the antenna is the same as it is attuned to the signal frequency not the type. The big difference with digital is that in weak fringe areas you get good reception or no reception, no weak fuzzy pictures.

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          #5
          I am a retired antenna engineer.

          There is no such animal as a "HD antenna", or "digital antenna", or "analog antenna."

          It's strictly a ploy be the manufactures to get people to discard the antenna which was satisfactory for years and buy a new one.

          Commonly called "marketing hype".

          The part which goes thru the air is RF energy, no matter what modulation scheme is used.

          Next on the list of taking advantage of customers lack of knowledge is: This is a "XXX mile antenna. The range is dependent on many things, such as transmitting power and antenna height; terrain, and such. 100 miles east of Denver, a set top TV antenna (rabbit ears) will work as the transmitting antenna is on a 10,000 foot high mountain, which is west of Denver, and Denver is 5,000 feet above sea level. So in effect its a 15,000 high antenna tower.
          Captharv 2001 2452
          "When the draft of your boat exceeds the depth of water, you are aground"

          Comment


            #6
            Captharv, since you are saving me some money, maybe, by not looking for the HD label, what should I be looking for in a marine antenna. The line of site in the region we live and boat in is pretty broken up by islands and mountains. Google earth Puget Sound up to the north end of Vancouver Island so you have an idea. Transmitters are in Victoria, Vancouver, Bellingham and Seattle. Antenna TV has always been a challenge here.
            P/C Pete
            Edmonds Yacht Club (Commodore 1993)
            1988 3818 "GLAUBEN”
            Hino EH700 175 Onan MDKD Genset
            MMSI 367770440

            Comment


              #7
              captharv, I just sent you a private message.11/10/17 20:20 hrs
              Dave
              Restoring/ upgrading: 1990 Ciera Sunbridge 2655 ST, "One Particular Harbour"
              5.7 Mercruiser Alpha 1 Gen 1 (my floating retirement villa if it doesn't kill me first)
              Sold:
              1995 SeaPro 210 C/C "Hydro-Therapy"
              Mariner 150
              Towing with:
              2002 Ford F 350 7.3L Super Duty
              Near High Rock Lake, N.C.

              Comment


                #8
                You can use tvfool.com to map your coordinates and elevation. It will show all broadcasting locations with predicted power at your point. You can use this information to aim a directional antenna.

                As far as choosing an antenna the highest gain is best without using a power amplifier. Most TV is broadcast in UHF frequencies. A few are still in VHF.
                Irony
                1989 Bayliner 4588 - EH700TI
                Portsmouth, NH

                Comment


                  #9

                  Right now I am staring at 2patent documents I have for television broadcasting and TV antennas. It seems the BOC Library is gone, so I'll try to ab lib it.
                  1st and this is a biggie. There is no such animal as a HD, analog or digital TV antenna. The media which goes thru the air is the same --- RF or radio frequency energy.
                  The words "HD ready" are nothing more than sale/marketing hype to get you to discard a good antenna and buy theirs. . If your antenna worked without snow in the picture it will most probably work for HD/Digital TV. Mine did very well. On the boat at Huntoon state park marina, I get 72 channels. The TV spectrum is divided into three bands Low (54-88 MHz) high 170-220) and UHF (470-800MHz). When the US went digital around 2006, the digitals were on UHF and the analog on the "normal" channels. The analog shut down and the digital stayed on uhf. The advantage is the higher the frequency the better a Smaller antenna will work.
                  Desirable is an amplifier at the antenna. It does help because digital broadcasting requires less signal to noise to operate, but more total signal. It kind of equals out.
                  Height is your friend. Use good quality RG 6U not RG 59 coax.
                  Now the bad part. The "gain" of antenna used to transmitting is measured to FCC specs so its numbers mean something. There is not such rules for TV antennas (and unfortunately VHF marine and CB) so the manufacture can fabricate gain figures in their sales/marketing dept., with no standards to dispute it. To get antenna gain (not amplifier) the elements must be longer than 1/4 wave. Example: for channel 2 at 54 MHz, the element is about 7+ feet. You can "tune" it so the element is only 8", but it will not collect signal from the air like a 1/4 wave or more will. Law of physics. So the signal is replaced by noise and an amplifier will help, but no get back the signal to noise ratio that the TV likes. Us engineers have a saying: "distrust the claims of an engineer for .5 ot 2 times whichever is apical. Distrust sales claims by .1 or 10....... So, height and bigger is better. I have the equivalent of a shakesphere 2030.
                  Now, amplifiers. There must be a "power injector" which sends DC up to the antenna, and plucks off the signal. Winegard makes one which is designed for a RV and mounts in a wall. Then, I ran the antenna coax thru the boat to a fitting on my hardtop. Makes for a neat install.
                  Another
                  cool thing about digital: many TV stations have live weather maps on one of their secondary channels. Great stuff for us boaters. This way you are not bound by the weather dummy on TV.
                  Captharv 2001 2452
                  "When the draft of your boat exceeds the depth of water, you are aground"

                  Comment


                  • Eyeman
                    Eyeman commented
                    Editing a comment
                    Wow. Awesome info dude. How about telling us what antenna (brand, model, etc...) to mount? We get the RG 6U coax. How about what amplifier (brand, model, etc....).

                  #10
                  Antennas I have tested and will recommend: the shakesphere 2030 or 2020, with a slight edge for the 2030.
                  They are amplified, and the power injector is near the TV where its supposed to be, not the antenna.
                  NOTE: I have not tested recently other antennas, so the ones sold today may or may not be good... (Note they will claim exurban amplifier gain but this does not cancel out bad antenna gain. The amplifier MUST be at the antenna, not the other end. Forget about add-on amplifiers. It shall not have metal support brackets. If you show steel brackets a picture of salt water, it will rust...
                  Some things to consider--- do you go to marinas or anchor outs relatively close to the TV transmitters or relatively far? I trailer all over Florida, so I designed my system for best fringe reception.

                  Here's my setup: The antenna comes with a 1" X 12 thread tapped hole on the bottom, which is the mount used on VHF and other antennas on a boat, so mounts and extensions are readily available over the counter (but, not cheap), so those who are mechanically challenged can do this. I have a stainless mount on the hardtop of my 2452. I also made up a 6' extension to raise the TV antenna up higher, giving me a 15' antenna height above the water. The antenna and mast detaches from the mount and is stored while trailing. The 2452 is about 12'6" above the road on the trailer and mounting any fixed antenna on the hardtop is asking for it....

                  There are two ways to bring the cable to the TV. 1. Run it thru the hatch to the supplied power injector to the TV or, as I did, buy a RV power injector wall plate at a RV store, mount it on the wall and fish the cable ( RG6U, please, to a point topside where you cab connect and disconnect easily. I simply used a TYPE F double female mounted thru a metal support with the inside connected to the run cable, and the outside attaches to the antenna lead.

                  In my backyard on the trailer, the TV gets 72 channels in the greater Orlando area. AT Huntoon Island state park marina, I get 66 channels. At Huntoon the tV transmitters average 35 miles from me.
                  Captharv 2001 2452
                  "When the draft of your boat exceeds the depth of water, you are aground"

                  Comment


                    #11
                    It looks like those Shakespeare 2020 and 2030 models have been discontinued. I wonder how the new 3019 model compares to those?
                    1998 3587 Bayliner, Port Orchard, WA

                    Comment


                      #12
                      I just looked at the shakes 3019. it would APPEAR to be the 2030 repackaged. I also know the parent manufacturer, Winegard, and their reputation as afr as antennas go, and I would recommend it, without having tested it.

                      A bit more on TV reception. The transmitter imparts electro magnetic radiation EMR into the air. The strength comes from transmitting power and the distance from height (provided there is enough power to fill the circle).
                      The receiving end, also, does depend on height. However, the antenna's ability to convert the EMR into electrical current to feed the TV is the difference. An example: Channel 2 requires an antenna element of about 5' and some kind of counter poise, or a 10' dipole. Reducing the presented surface to, say 2' results in a loss of pickup. Electronically, it can be impedance matched, but you cannot make it pick up more signal than its real length. So the only variable you have is height with a given antenna.

                      The poster said he got a lot more stations at high tide. This falls in place with height. So, what did I do? The pic below is my boat. The shakesphere antennas mentioned come with a mounting hole with female 1X14 thread common to boating antennas. Mounts and extensions are available, although a bit pricy, to extend the antenna to 10' over the mount. I have 2 five footers I can couple to make it high, as well as a mount on the hardtop. The hardtop and a 5 ' gives me 13' above the water and usually suffices. If I were in a mountainous state, I would make up a custom telescoping mount and go 20' above the mount, and use a 2 pc mount like they do on the 21" SSB antennas.

                      Nextly: Cable. The RG 59U which comes with the antenna is more suited for audio. Use a good quality RG 6U. It's less lossy, and this is important as most broadcasting is in the High VHF and UHF bands.

                      Here's a hint: Omnidirectional horizontal antennas are SOMEWHAT omnidirectional. There are some nulls and peaks. Not much but is could be the difference between viewable or not especially with digital TV. When you mount the antenna, mount it so it can be rotated somewhat. On the LED TVs they usually have access to a bar graph signal meter (shades of cellphone!). Someone can call out the bars while someone can rotate for best signal. Even in Florida where the terrain is flat, rotating makes a difference.

                      With the above knowledge, play with it to get the best reception.
                      Captharv 2001 2452
                      "When the draft of your boat exceeds the depth of water, you are aground"

                      Comment

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