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  • Originally posted by mickopla View Post
    Thanks abcd567 for the link. Last night i made a 3 element CoCo for testing. I'm tempted to use this instead of the 9 element one i was using previously. What would the main differences be between using 3 element and 9?

    Mike
    Apparently 9 element antenna should give a better result than 3 element antenna.
    The best way to find out is to try both the 3 element & 9 element antennas, and compare results.

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    • Originally posted by abcd567 View Post
      Apparently 9 element antenna should give a better result than 3 element antenna.
      The best way to find out is to try both the 3 element & 9 element antennas, and compare results.
      I removed the coax coupler and put the amp in its place and now all is working well,thankfully without a trip up the ladder

      Results wise not a big jump in tracking distances but definitely tracks coming from most directions unlike when the antenna was in the attic. The max pick up i'm getting is 320km away. See attached for an adsbscope screen grab from a while ago.

      Edit: I'm wondering does having the amp in the middle of a 30 foot run to Antenna make any difference to performance as opposed to having it just after the power inserter at the start of the run?

      Mike
      17-12-2013 20-03-46.jpg
      Last edited by mickopla; 2013-12-17, 20:37. Reason: Adding question

      Comment


      • Originally posted by mickopla View Post
        I removed the coax coupler and put the amp in its place and now all is working well,thankfully without a trip up the ladder

        Results wise not a big jump in tracking distances but definitely tracks coming from most directions unlike when the antenna was in the attic. The max pick up i'm getting is 320km away. See attached for an adsbscope screen grab from a while ago.

        Mike
        [ATTACH=CONFIG]3081[/ATTACH]
        Increasing the height of receiving antenna has negligible effect on range in all those directions where antenna can "see" the horizon. Just place your eyes at location of antenna, and if you see the horizon, antenna also sees the horozon. In all those direction in which antenna can see horizon, it's range is maximum.

        Increasing antenna height has a profound effect in those directions where view of horizon was obstructed. As the antenna is raised, it's range also increases, till it is just above that obstruction height, and can now see the horizon in that direction also. Increasing antenna an further does not increase the range.

        Sent from my N762 using Tapatalk 2
        Last edited by abcd567; 2013-12-17, 21:26.

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        • Originally posted by abcd567 View Post
          Increasing the height of receiving antenna has negligible effect on range in all those directions where antenna can "see" the horizon. Just place your eyes at location of antenna, and if you see the horizon, antenna also sees the horozon. In all those direction in which antenna can see horizon, it's range is maximum.

          Increasing antenna height has a profound effect in those directions where view of horizon was obstructed, and antenna is raised above that obstruction height, and can now see the horizon in that direction also.

          Sent from my N762 using Tapatalk 2
          This may have been lost in my previous post but I'm wondering does having the amp in the middle of a 30 foot run to Antenna make any difference to performance as opposed to having it just after the power inserter at the start of the run?

          Mike

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          • Originally posted by mickopla View Post
            This may have been lost in my previous post but I'm wondering does having the amp in the middle of a 30 foot run to Antenna make any difference to performance as opposed to having it just after the power inserter at the start of the run?

            Mike
            Amplifier's location should not make any noticeable difference if your cable run is not long (only 30 feet). However as a general rule placing amplifier close to antenna is desireable, as this way noise picked up by the coaxial cable along it's length is not amplified by amplifier

            Sent from my N762 using Tapatalk 2
            Last edited by abcd567; 2013-12-17, 22:17.

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            • Originally posted by abcd567 View Post
              Amplifier's location should not make any noticeable difference if your cable run is not long (only 30 feet). However as a general rule placing amplifier close to antenna is desireable, as this way noise picked up by the coaxial cable along it's length is not amplified by amplifier

              Sent from my N762 using Tapatalk 2
              Thats good to know. Probably my next step will be to test the shorted version of the coco and see what results i get. It seems its the way to go. Just a quick question with regards the capacitor that is needed when using the amp and power inserter. Is it home made or can it be bought online?

              Mike

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              • Originally posted by mickopla View Post
                .........Just a quick question with regards the capacitor that is needed when using the amp and power inserter. Is it home made or can it be bought online?

                Mike
                No the capacitor and it's housing are NOT home made. Housing is an ordinary tv splitter ($2) with its internal parts removed. Capacitor is very cheap (25cents) is to be purchased either from an electronics/radio shop, or ordered online. Postage will be many times the cost of capacitor
                Better find out radio/electronics repairs or parts shops in your city.


                Sent from my N762 using Tapatalk 2
                Last edited by abcd567; 2013-12-18, 01:11.

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                • Originally posted by mickopla View Post
                  .......Just a quick question with regards the capacitor that is needed when using the amp and power inserter. Is it home made or can it be bought online?

                  Mike
                  I remember some one has recently posted a brillian idea of using 2nd power inserter, but without connecting dc adapter to it, to provide dc blocking. The 2nd power inserter is to be connected between amplifier and antenna, it's HF+DC connected to Amplifier's LNB terminal, HF to antenna cable, IN left unconnected. The power inserter has a capacitor inside it.


                  Sent from my N762 using Tapatalk 2

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                  • Originally posted by abcd567 View Post
                    I remember some one has recently posted a brillian idea of using 2nd power inserter, but without connecting dc adapter to it, to provide dc blocking. The 2nd power inserter is to be connected between amplifier and antenna, it's HF+DC connected to Amplifier's LNB terminal, HF to antenna cable, IN left unconnected. The power inserter has a capacitor inside it.


                    Sent from my N762 using Tapatalk 2
                    Very inventive to use the power inserter in that way.

                    On another subject i'm wondering can the MCX aerial that came with the dongle be modified in some way to connect coax to the other end. This would save buying a mcx to coax converter?
                    Also what settings are used in adsbscope to get the max tracks like abcd567 has for testing?

                    Regards

                    Mike

                    Comment


                    • Originally posted by mickopla View Post
                      ........On another subject i'm wondering can the MCX aerial that came with the dongle be modified in some way to connect coax to the other end. This would save buying a mcx to coax converter?..........
                      Mike
                      This is a 'hack job' I did previously. I cut the cable from antenna which came with DVB-T Dongle, and soldered it to coaxial cable. Similar as you soldered DC Adaptor wire to coax from inserter. See photo below:

                      pm5.gif

                      Sent from my N762 using Tapatalk 2

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                      • Originally posted by abcd567 View Post
                        This is a 'hack job' I did previously. I cut the cable from antenna which came with DVB-T Dongle, and soldered it to coaxial cable. Similar as you soldered DC Adaptor wire to coax from inserter. See photo below:

                        [ATTACH=CONFIG]2763[/ATTACH]

                        Sent from my N762 using Tapatalk 2
                        So positive to center and negative to braid?

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                        • Originally posted by mickopla View Post
                          So positive to center and negative to braid?
                          centre to centre, braid to braid!
                          technically speaking its a gash connection and will have a high loss (lost signal)

                          Sent using Tapatalk from my ZX81

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                          • Originally posted by mickopla View Post
                            So positive to center and negative to braid?
                            Originally posted by Rooster View Post
                            centre to centre, braid to braid!
                            technically speaking its a gash connection and will have a high loss (lost signal)

                            Sent using Tapatalk from my ZX81
                            The cable which you will cut from the DVB-T Dongle's antenna is a coaxial cable, but smaller diameter. So you will make a coaxial-to-coaxial joint, and as Rooster said "core to core, braid to braid. Well, in my original post I have declared it a ' hack job', but it works without any significant loss of signal, and makes the setup take off even if you dont have proper parts.

                            Sent from my N762 using Tapatalk 2

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                            • Originally posted by Rooster View Post
                              centre to centre, braid to braid!
                              technically speaking its a gash connection and will have a high loss (lost signal)

                              Sent using Tapatalk from my ZX81
                              "centre to centre, braid to braid!" reminds me the phrase "earth to earth, ashes to ashes, dust to dust" said at funeral services


                              Sent from my N762 using Tapatalk 2

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                              • Originally posted by Rooster View Post
                                centre to centre, braid to braid!
                                technically speaking its a gash connection and will have a high loss (lost signal)

                                Sent using Tapatalk from my ZX81
                                Yes Rooster, you are right, but in a different situation... if the antenna is connected to transmitter & handles power in watts or hundreds of watts, such type of joints will be a disaster. Here we are dealing with a receiving antenna, handling milli or micro Watts, and such joints work fairly good.

                                I do not recommend such jobs as a permanent installation, but as a temporary measure to get the project going, even if there is a limitatin of resources.

                                Sent from my N762 using Tapatalk 2
                                Last edited by abcd567; 2013-12-19, 03:19.

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