Announcement

Collapse
No announcement yet.

best antenna

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Originally posted by jcinnb View Post
    are you zip tying the radials to outside of cable, or stuffing them down in the insulation. My eyes are not what they used to be?
    All the 4 radials were inserted between the outer PVC jacket and the braid of the coax. The zip ties were used to secure the radials in position, as these have a tendency to move and change 90 degree angle with each other.

    After completion, I checked the continuity between the body of F-connector at other end of coax, and each of 4 radials by a multitester. All 4 were found electrically continuous, as the multitester beeped on each radial.

    The radials were inserted in the same way as a center wires of a Coco are inserted between the PVC jacket and braid of adjacent elements.

    Here is a larger size photo of the monopole with radials inserted and zip-tied.

    Comment


    • Got it, thank you.

      Comment


      • My "Super" coco, the experiment continues...
        from 202nm to 295nm with wideband amplifier and 1090 MHz filter
        Coco + LNA+Filter.jpg
        Coax (75 Ohm 707CRT2) go in the chimney...
        Coco schouw.jpg
        the result:
        Coco special 1...jpg

        total height of 6 meters + 1 meter Antenna (8 x 114 mm)
        20160919_181134.jpg
        Last edited by Ronny Jonckers; 2016-09-21, 08:02.

        Comment


        • I became a little tired of all this blind probing. It takes too much time to fine tune antennas, cables, filters, stubs etc.
          Weather is also not helping as it rains much and I can't open my roof windows to put up test rigs.

          I came upon this article and ordered all that I needed, mainly the noise source, some filters, a metal encased SDR and a directional coupler.
          Waiting starts now but I will jump on some SWR tests the moment all parts arrive.

          Edit: definitely becoming a costly hobby...
          Last edited by ccz; 2016-09-20, 22:28.

          Comment


          • My "Super" PCB, now with wideband amplifier and 1090 MHz filter.
            20160907_144217.jpg
            Same configuration as by the coco, but with 50 Ohm H155 coax, top height 6 meter (top chimney) + 50 cm (pvc tube + PCB Antenna)
            LNA+Filter.jpg
            P9210003.jpg
            The result: from 105nm to 321nm
            Super PCB.jpg
            Last edited by Ronny Jonckers; 2016-09-21, 11:53.

            Comment


            • Originally posted by ccz View Post
              I became a little tired of all this blind probing. It takes too much time to fine tune antennas, cables, filters, stubs etc.
              Weather is also not helping as it rains much and I can't open my roof windows to put up test rigs.

              I came upon this article and ordered all that I needed, mainly the noise source, some filters, a metal encased SDR and a directional coupler.
              Waiting starts now but I will jump on some SWR tests the moment all parts arrive.

              Edit: definitely becoming a costly hobby...
              Great!
              Some noise sources heat up too much. I purchased one which became so hot I used to fry eggs on it . Few days after purchase, it burned itself to death
              Someone has installed on his similar noise source, a recycled cooling fan from a discarded video card, and it is still surviving.

              Comment


              • Originally posted by Ronny Jonckers View Post
                My "Super" PCB, now with wideband amplifier and 1090 MHz filter.
                .....image snipped.......
                Same configuration as by the coco, but with 50 Ohm H155 coax, top height 6 meter (top chimney) + 50 cm (pvc tube + PCB Antenna)
                .....image snipped.......
                .....image snipped.......
                The result: from 105nm to 321nm
                .....image snipped.......
                Wow, great, congratulations.

                Comment


                • Originally posted by Ronny Jonckers View Post
                  The result: from 105nm to 321nm
                  [ATTACH=CONFIG]8048[/ATTACH]
                  Nice, good work!
                  Would you mind posting also the lower part of the stats? Just pick a full day on this antenna.
                  I am interested in the histogram mostly.

                  Here is my spider:
                  charts.png



                  Originally posted by abcd567 View Post
                  Great!
                  Some noise sources heat up too much. I purchased one which became so hot I used to fry eggs on it . Few days after purchase, it burned itself to death
                  Someone has installed on his similar noise source, a recycled cooling fan from a discarded video card, and it is still surviving.
                  Thanks for the advice, will look out of excessive heat.
                  I ordered 2 different models, both were around 15$. I could make a mini review of them after trying them out.

                  Comment


                  • @ccz
                    The lower parts of the stats:
                    Plot and Histogram.JPG
                    When I move the mouse over the histogram, I see
                    46 trackings above 150nm With a maximum of 321nm
                    1x160nm
                    1x166nm
                    1x172nm
                    1x173nm
                    1x174nm
                    1X177nm
                    1x178nm
                    3x179nm
                    1x180nm
                    1X184nm
                    1x186nm
                    5x197nm
                    1x200nm
                    1x202nm
                    3x206nm
                    1x212nm
                    2x213nm
                    2x214nm
                    1x220nm
                    1x226nm
                    1x233nm
                    1x241nm
                    1x251nm
                    1x258nm
                    1x260nm
                    1x264nm
                    1x273nm
                    1x275nm
                    1x283nm
                    1x292nm
                    1x301nm
                    1x302nm
                    1x309nm
                    1x312nm
                    1x315nm
                    1x321nm

                    Comment


                    • @volkerjacob:

                      1) You need to compare your 8+1/4 λ CoCo with a reference antenna at same location and heigt to asses how good/bad your CoCo is.

                      A 1/4 λ Ground plane antenna is a 'sure and easy to make' antenna, and serves as a good reference/benchmark antenna.

                      2) What is GFK? Can you please give it's full name?

                      3) Increasing antenna height improves range/plane count/messages.

                      Comment


                      • Originally posted by abcd567 View Post
                        @volkerjacob:

                        1) You need to compare your 8+1/4 λ CoCo with a reference antenna at same location and heigt to asses how good/bad your CoCo is.

                        A 1/4 λ Ground plane antenna is a 'sure and easy to make' antenna, and serves as a good reference/benchmark antenna.

                        2) What is GFK? Can you please give it's full name?

                        3) Increasing antenna height improves range/plane count/messages.
                        GFK /sorry german) = GFRP Glas Fiber Reinforced Plastic - at the moment i use a PCV tube ....

                        at same location with a G-7RGQ i got only around 15000 frames with 100 nm max range. Location is in my garden 1m under roof - new location would be at roof....
                        Best Regards

                        Volker

                        Comment


                        • Hi to all who have posted on this thread, I bumped into flight tracking by accident looking for something completely different.
                          I have taken the time to read every post in this thread, and had to register to see the pictures, there's a lot of dedication from the posters and a wealth of information.
                          I've had my setup on test for a couple of weeks and am using a Raspberry Pi Zero and a mini iPad, like most I started with the standard antenna that came with the dongle, when I looked it had a m3 stub so I used a brass circuit board post and a m3 cap screw to make a 1/4 wave antenna, that showed an improvement. I was set on building a coco but as I progressed further down the thread I went of the idea due to the inconsistency reported, in the end I settled for a jpole, that has given me a further improvement. At the moment I'm working on one of these.

                          0866680A-7B59-445B-9F17-61525EAD2554_zpsuguoq0o6.jpg
                          I used one for APT a number of years ago and it was definitely the best for that job, but I think at 1090 MHz accuracy will be the big hurdle.

                          Dave

                          Comment


                          • Originally posted by DavidH View Post
                            Hi to all who have posted on this thread, I bumped into flight tracking by accident looking for something completely different.
                            I have taken the time to read every post in this thread, and had to register to see the pictures, there's a lot of dedication from the posters and a wealth of information.
                            I've had my setup on test for a couple of weeks and am using a Raspberry Pi Zero and a mini iPad, like most I started with the standard antenna that came with the dongle, when I looked it had a m3 stub so I used a brass circuit board post and a m3 cap screw to make a 1/4 wave antenna, that showed an improvement. I was set on building a coco but as I progressed further down the thread I went of the idea due to the inconsistency reported, in the end I settled for a jpole, that has given me a further improvement. At the moment I'm working on one of these.

                            [ATTACH=CONFIG]8062[/ATTACH]
                            I used one for APT a number of years ago and it was definitely the best for that job, but I think at 1090 MHz accuracy will be the big hurdle.

                            Dave
                            Dave, it should be possible to build one accurately enough, in the past I have successfully made quadrifilar antennae for GPS reception, however ADSB signals are not circularly polarised so I don't know how successful this would be, please give it a try and post your results.
                            FR24 F-EGLF1, Blitzortung station 878, OGN Aldersht2, PilotAware PWAldersht, PlanePlotter M7.

                            Comment


                            • Originally posted by volkerjacob View Post
                              GFK /sorry german) = GFRP Glas Fiber Reinforced Plastic - at the moment i use a PCV tube ....

                              at same location with a G-7RGQ i got only around 15000 frames with 100 nm max range. Location is in my garden 1m under roof - new location would be at roof....
                              If you were wondering (since I see you also deleted another message saying you don't like forums due to moderation)

                              It's because you were quoting someone within 5 posts with @s. Naminly abcd567 trying to get your attention like you would on twitter (or a spam post with contact details for UNLOCKED IPHONE7 etc

                              Unfortunately the side effect of the auto moderator is it does not notify us of it, and we have to look out for the mention on the post itself. Don't read the thread often = goes unnoticed.
                              Posts not to be taken as official support representation - Just a helpful uploader who tinkers

                              Comment


                              • Originally posted by F-EGLF1 View Post
                                Dave, it should be possible to build one accurately enough, in the past I have successfully made quadrifilar antennae for GPS reception, however ADSB signals are not circularly polarised so I don't know how successful this would be, please give it a try and post your results.
                                I never gave it thought, I have built 3 and I can confirm its not the way to go, planes went down from 80+ to 40, messages went down from 600+ to 500, but all these bits of bent wire have there own personality, I lose aircraft landing at Gatwick around 2500 ft but with the quad I can see them down to 1200 ft. One steep forward two steps back, the only problem is the steps back are bigger then the steps forward, I did try one with the twist taken out so the elements were vertical but that wasn't any good either.

                                Well not one to be beaten I'm trying a bicone at the moment and early indications are it just has the edge over the jpole.

                                B5B45D59-595C-4D9F-87FE-12350A9FA717_zpsjuwgdmvt.jpg


                                Dave

                                Comment

                                Working...
                                X