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3 EASY ANTENNAS FOR BEGINNERS

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  • #76
    Some Examples of Outdoor Installation of Cantenna

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    • #77
      @abcd567, yes! I think that 1 or 2 meters higher will help and is not hard to do! Let's see! Besides, today arrived from China (AliExpress) a antenna that i bought by 3US$! I'll let VR do the range plot and see if its better than the original one that come with the dvb-t! I'll test in the other Radar, the T-SBCT6 that are inside my house!

      This is the antenna!
      IMG_3555.jpg
      T-SBCT5/T-SBCT6

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      • #78
        SOME MORE EXAMPLES OF OUTDOOR INSTALLATION OF CANTENNA




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        • #79
          Originally posted by dudesjp View Post
          @abcd567, yes! I think that 1 or 2 meters higher will help and is not hard to do! Let's see! Besides, today arrived from China (AliExpress) a antenna that i bought by 3US$! I'll let VR do the range plot and see if its better than the original one that come with the dvb-t! I'll test in the other Radar, the T-SBCT6 that are inside my house!

          This is the antenna!
          [ATTACH=CONFIG]7160[/ATTACH]
          I also purchased similar antenna for $5 (price+shipping) from eBay last month. Not so good as advertised.
          The the original one that come with the dvb-t, when cut to 52 mm, proved better, Click here: Post #8, Optimize the Whip Antenna Which Is Supplied With DVB-T Dongle


          Also see this one:
          Click here: My post in Flightaware Forum

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          • #80
            This has been a great read always veered off making antennas as I'm new to this stuff.

            Made my first cantenna last night think I need to do it again as the tin is just shy of 69mm.
            Last edited by andrewh_85; 2016-03-16, 13:19.

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            • #81
              @andrewh_85:
              1) Few mm more or less in tin height is not critical.
              2) Reducing height of whip by 2 to 3 mm i.e making whip height 66 or 67 mm instead of 69 mm gives some noticeable improvement. This is due to the phenomenon called "end effect" which causes this.

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              • #82
                Cheers abcd567 will give it another go and see how I get on.

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                • #83
                  I made my first spider and will put it to the roof asap. Actually I am using a modified DVB antenna in the attic under the insulated roof: removed the whip, soldered a copper to a nut and attached to the antenna foot so that I have the recommended 52 mm, respecting the "antenna" inside the foot.
                  Next:
                  2016-03-18_0929.jpg
                  Old (you can see the pole on the right side that is going through the roof for SAT antenna where my spider will also be attached to):
                  P1040690.jpg
                  JRF: T-EDNY19
                  South Germany

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                  • #84
                    @jrf:
                    Nice to see your innovation. You are the first one I know who has used a F barrel connector (F female - F female) with a rectangular plate, instead of SO239 or N connector.

                    Using a 52mm copper wire soldered to a nut with the whip antenna is also very innovative.

                    The other alternative was to cut the original whip to 52mm, as shown in my post #8 in the thread "Optimize the Whip Antenna Which Is Supplied With DVB-T Dongle". CLICK HERE

                    .
                    Last edited by abcd567; 2016-03-18, 20:38.

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                    • #85
                      I just built a J Antenna, from a piece of 2,5mm˛ cooper wire.
                      It was very easy to build. It is now taped on the window and works much better than the T, that I have built before.
                      The nice thing with that antenna, is that it shortcuts all low frequencies very well.
                      That is important since the reciever is broad-banded.

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                      • #86
                        Originally posted by RIN67630 View Post
                        I just built a J Antenna, from a piece of 2,5mm˛ cooper wire.
                        It was very easy to build. It is now taped on the window and works much better than the T, that I have built before.
                        The nice thing with that antenna, is that it shortcuts all low frequencies very well.
                        That is important since the reciever is broad-banded.
                        Make a Spider or Cantenna (see beginning of this thread), and you will find these two much better than J-Pole.

                        For indoor use, Cantenna is particularly good & easy to make, and unlike Spider, it does not require any special connectors like SO239 & PL259.
                        Last edited by abcd567; 2016-03-20, 00:53.

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                        • #87
                          Originally posted by abcd567 View Post
                          Make a Spider or Cantenna (see beginning of this thread), and you will find these two much better than J-Pole.

                          For indoor use, Cantenna is particularly good & easy to make, and unlike Spider, it does not require any special connectors like SO239 & PL259.
                          Got my Cantenna made and indoors its giving me an extra 20 miles over the stock antenna.

                          Wish I had made it before ordering a antenna lol

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                          • #88
                            Spider put to work. Let's wait for results: VRS. Known Limits: montainous environment, European Alps to the South, a hill nearby with a castle to the West.
                            P1040693.jpgP1040694.jpgP1040696.jpg
                            JRF: T-EDNY19
                            South Germany

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                            • #89
                              The spider or the cantennas are nothing else than a 1/4 λ ground plane with a maximum gain of 1.
                              The J antenna is a 5/8 λ which gets ideally 3dB more.

                              It has moreover the advantage of being electrically shortcuted and rejects pretty well all low frequencies.
                              The construction is very easy, just bend a piece of 2,5mm˛ copperwire and solder the coax cable.
                              The balun can be made of the same coax cable (original cable) which eliminates all connector losses.
                              The Raspi is (here together with a sound metering station) is housed waterproof in an IP65 casing
                              Here the photograph without cover and mounted for testing in front of a window.
                              The next step is to put the J antenna in a piece of 16mm PVC pipe and to put everything on a terrace close to the roof.
                              http://www.cjoint.com/doc/16_03/FCvr...321-175050.jpg

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                              • #90
                                Originally posted by RIN67630 View Post
                                The spider or the cantennas are nothing else than a 1/4 λ ground plane with a maximum gain of 1.
                                The J antenna is a 5/8 λ which gets ideally 3dB more.
                                How is the J pole regarding the full 360 degrees circle?
                                What would one do if the antenna is not taped to a window but to be put on to the roof?
                                JRF: T-EDNY19
                                South Germany

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