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  • Originally posted by Jarod View Post
    http://x264.nl/dump/2012/ads-b-anten...ane-proper.jpg works best here.
    This GP gets about 20nmi more than the FR24 antenna.
    FR24: 210-230nmi
    GP: 230-250nmi
    Tested on the FR24 receiver and Airspy
    REALLY? how high it is?

    Comment


    • Originally posted by Jarod View Post
      http://x264.nl/dump/2012/ads-b-anten...ane-proper.jpg works best here.
      This GP gets about 20nmi more than the FR24 antenna.
      FR24: 210-230nmi
      GP: 230-250nmi
      Tested on the FR24 receiver and Airspy
      Are you sure that is correct, I use an FR24 Antenna with their receiver and in some directions easily break the 300nmi distance...! I appreciate that I am 176m [AMSL] but compared to the Cantenna's and Colinears I have made and tested, they don't get anywhere near those kind of distances.
      If life is a stage, most of us are unrehearsed...!

      Comment


      • Originally posted by DemonLee View Post
        Are you sure that is correct, I use an FR24 Antenna with their receiver and in some directions easily break the 300nmi distance...! I appreciate that I am 176m [AMSL] but compared to the Cantenna's and Colinears I have made and tested, they don't get anywhere near those kind of distances.
        With these cheap and handmade antennas you need a bit of luck too.
        It seems my GP is the perfect length on the vertical and radial. This is 100% luck, as i just cut it on about 6.54 cm if i can recall next to the measure lint.

        Next antenna to test will be:
        http://shop.jetvision.de/epages/6480...oducts%2F68200 "Active Diapason" Antenna (1090 MHz)

        Will keep ya all posted.

        Comment


        • .
          This post was deleted as it is now a separate thread (click the link below):

          A 3/4 λ Collinear Groundplane Antenna
          Last edited by abcd567; 2016-02-11, 03:32.

          Comment


          • Originally posted by Jarod View Post
            With these cheap and handmade antennas you need a bit of luck too.
            It seems my GP is the perfect length on the vertical and radial. This is 100% luck, as i just cut it on about 6.54 cm if i can recall next to the measure lint.
            All the collinear antennas are easy to make but very hard to get right in DIY enviroment. Example of such collinears are coaxial collinear (coco), wire collinear (whip with coils), franklin collinear (dipole with stubs).

            The reason the collinears are hard to get right is that these are highly intolerent to dimmensional errors cased by poor design and/or poor construction. A few mm error can push these antenna from "excellent" to "poor" category. These need test equipment to trim & tune to get them work properly, but most DIY antenna makers lack these instruments.

            On the other hand a 1/4 wavelength GP (groundplane) antenna is not only naturally tuned, but has a high dimensional tolerance, and is not knocked out by few mm error in dimensions. It therefore works good even without tuning with the help of test equipment.

            Here is a tip for GP antenna makers: enlarge the horizontal part of groundplane to dia = 1/4 wavelength

            The GP antenna is usually built using a N-connector or SO239-connector. The 1 inch x 1 inch (25 mm x 25 mm) flange of these connectors is part of the groundplane of the antenna. If this horizontal part of groundplane is enlarged to have a dia nearly equal to 1/4 wavelength, while keeping the radials 1/4 wavelength from the outer edge of horizontal part, the performance of GP improves.

            I have experienced this magical effect when I tried Canrennas with can diameters 20mm, 54mm, 68mm & 100mm. The best result was obtained whith the can dia 68mm i.e. the dia of bottom of can was 68mm, almost 1/4 wavelength.

            Some other users have tried horizontal flange enlarged to 2.5 inches (63 mm, nearly 1/4 wavelength), and have reported enhanced performance. Photo of these GP are given below.

            Cantenna with different can dia / bottom dia





            Example of 2 GPs with groundplane enlarged to 2.5 inch dia (nearly 1/4 wavelength).

            TomW's GP with 2.5 inch / 63 mm dia disc. Click here



            blueskyspotter's GP - Click here





            F1Rocket's/gnuse's GP - Click here
            Last edited by abcd567; 2016-02-11, 03:50.

            Comment


            • Originally posted by Jarod View Post
              With these cheap and handmade antennas you need a bit of luck too.
              It seems my GP is the perfect length on the vertical and radial. This is 100% luck, as i just cut it on about 6.54 cm if i can recall next to the measure lint.

              Next antenna to test will be:
              http://shop.jetvision.de/epages/6480...oducts%2F68200 "Active Diapason" Antenna (1090 MHz)

              Will keep ya all posted.
              Long story short: It's a good antenna. It will decode those extra few weak frames. As i can see on range, adding about 10nmi and at close range, more ground traffic visible.
              But when you are at a location which is high and has a good 360 degrees view, the upgrade from the standard FR24 antenna is not worth it.

              Please note: Tested in The Netherlands, Amsterdam.
              The Netherlands is a very low country and a lot of it is below sea level. This severely limits my range.
              But still being in the top 70 isn't that bad. But it can't be improved by a better antenna. I guess i need to find another 100m upwards.

              Comment


              • The "Pro Stick", a dvb-t dongle with built-in amplifier. It has SMA female connector on the end. The generic dvb-t dongle has MCX connector on the side.



                "Canceiver" using the new dongle.

                .

                Comment


                • The Canceiver

                  Cantenna + Flightaware Pro Stick (dvt-b) + right angle bend usb-female to usb-male + Orange Pi PC




                  The FlightAware ProStick has SMA Female connector. Used SMA Male to F Female adaptor on top of it.

                  Last edited by abcd567; 2016-05-20, 23:21.

                  Comment


                  • I must admit I'm new to this, and I have just started feeding (T-YHBA5) but I'm in the process of getting my setup sorted.

                    I have it mounted on my tv antenna mast, using a 1m aluminum pole extension to ensure it's higher than the tv stuff and has a clear view.
                    But my issue is -

                    When first testing, I used a 10m cable from the antenna and had it mounted just on top of tv antenna pole (no extention), my range was good, and possibly 50nm more than now.

                    Since I added 5 m more of LL cable and raised the antenna 1m above where it was, my range has dropped. Could it be because of the aluminum mast - should I have used galv. steel ? 5m more cable ?

                    I have another option, where I can mount the antenna lower, on the roof of the verandah/patio, it will have a clear view of the sky, just 3m lower overall and not above the roofline.

                    Will probably be trial and error but without drilling too many holes in my roof any suggestions?


                    **Ive attached a photo showing the antenna on the 1m extension and you can also see the previous height of the tv mast.

                    Thanks in advance - I'm only learning IMG_0491.jpg
                    T-YHBA5

                    Comment


                    • Cable Distance + new connectors = more loss before receiver

                      Sent from my XT1092 using Tapatalk
                      Posts not to be taken as official support representation - Just a helpful uploader who tinkers

                      Comment


                      • Thanks Oblivian, back to a 10m cable, and antenna 1m lower than before - compromise but coverage up to 124nm from about 60-70nm with the 5m of extra coax i had before.

                        Originally posted by Oblivian View Post
                        Cable Distance + new connectors = more loss before receiver


                        Sent from my XT1092 using Tapatalk
                        T-YHBA5

                        Comment


                        • Originally posted by Oblivian View Post
                          Cable Distance + new connectors = more loss before receiver
                          Originally posted by jpsimmo View Post
                          Thanks Oblivian, back to a 10m cable, and antenna 1m lower than before - compromise but coverage up to 124nm from about 60-70nm with the 5m of extra coax i had before.
                          Why not add a Satellite amplifier. You will then be able to add extra cable to raise your antenna. The Satellite amplifier has a gain around 15 to 20 dB, whereas loss in your extra coax & connectors will not be more than 3 dB. The amplifier will not only cover for losses in cable & connectors, but will also boost the signal. Your range will increase substantially.


                          http://www.ebay.com/sch/i.html?_nkw=...lite+amplifier
                          Last edited by abcd567; 2016-05-22, 06:27.

                          Comment


                          • Originally posted by abcd567 View Post
                            Why not add a Satellite amplifier. You will then be able to add extra cable to raise your antenna. The Satellite amplifier has a gain around 15 to 20 dB, whereas loss in your extra coax & connectors will not be more than 3 dB. The amplifier will not only cover for losses in cable & connectors, but will also boost the signal. Your range will increase substantially.
                            I could do that, I must apologize that I'm new to this, but keen to learn. Is there any specific satellite amplifier I should use? I'm limited with what local stores can stock here, so Ebay is my best option,
                            Thanks in advance
                            T-YHBA5

                            Comment


                            • This is what I use (RCA D903, 950 Mhz - 2050 Mhz, 13 - 18 dB) purchased from local store for $4.

                              However it is not necessary that you use this model. There are a very large number of equally good satellite amplifiers available on ebay. Search ebay for "satellite amplifier" and you will get a big list.

                              RCA D903.jpg
                              Last edited by abcd567; 2016-05-22, 06:47.

                              Comment


                              • Originally posted by abcd567 View Post
                                This is what I use (RCA D903, 950 Mhz - 2050 Mhz, 13 - 18 dB) purchased from local store for $4.

                                However it is not necessary that you use this model. There are a very large number of equally good satellite amplifiers available on ebay. Search ebay for "satellite amplifier" and you will get a big list.

                                [ATTACH=CONFIG]7528[/ATTACH]
                                Thank you! I will invest in one of these, or similar in the next couple of weeks! I take it these need to be powered? Where I live there should be little interference so I'm hoping this may boost coverage just a bit more !
                                T-YHBA5

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