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  • #46
    Originally posted by Birdie View Post
    Huh ? F-WSSS1 get about 600 km. I am very sure I can't see 600 km with my eyes.
    He is correct. It is not a good idea to rely on much more than "line of sight" when trying to figure out ranges. Line of sight doesn't necessarily mean what your eyes can see.
    He is also correct with the remarks re trees & buildings etc. Rain also makes a huge difference at these frequencies; see what happens to your satellite TV in a heavy rain storm.
    A couple of other things that would affect range are aircraft transponder power, aircraft altitude and receiver sensitivity (not to mention antenna gain & feeder losses)
    I have no idea of receiver sensitivity but I have seen figures of -90dBm at 981 MHz and -71 dBm at 1090 MHz.
    Using those figures, 600Km is really pushing your luck at 1090 MHz; the theory says the received signal will be about -90dBm.
    Having said that, experience has shown me that when it comes to propagation, the theory rarely matches the practice!
    Some years ago, my colleagues and I provided the late King Hussein with a hand held radio (the same sort of thing supplied to police forces etc), operating on 144 MHz and he was able to talk with the people on board Spacelab. He couldn't see it but he could talk to it!

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    • #47
      Originally posted by Birdie View Post
      Huh ? F-WSSS1 get about 600 km. I am very sure I can't see 600 km with my eyes.
      I can see the moon at night. Pretty sure that's more than 600 km away. 'Line of sight' distance increases significantly with height.
      Rob, VK6UFO
      F-YPPH3
      o410E


      Comment


      • #48
        Originally posted by VK6UFO View Post
        I can see the moon at night. Pretty sure that's more than 600 km away. 'Line of sight' distance increases significantly with height.
        hahahahaaaaa .... Very good answer.

        Hope this answers most of the questions Newbies having been asking.
        F-WSSS1 - Cats refused to Pee & Pooh on RadarBox - Running a FR24 Receiver & DVB-T Dongle 24/7 to piss off The Chief Thief.

        Comment


        • #49
          Originally posted by Even92LN View Post
          The lenght of the cable has nothing to do with the antennas frequency range. But the longer cable you have, the more signal loss.
          The frequency of the signal you want to receive does influence the signal loss. There is different kinds of coax cables, ex: RG 58, LMR 100, LMR 400, RG 213, H155 just to mention some. They have different losses per meter but it's related to the frequency.

          Here's the example from an H155 coaxial:

          10 MHz: 3.0 dB/100m
          50 MHz: 6.5 dB/100m
          100 MHz: 9.3 dB/100m
          230 MHz: 14.2 dB/100m
          300 MHz: 16.3 dB/100m
          400 MHz: 19.0 dB/100m
          470 MHz: 20.7 dB/100m
          860 MHz: 28.5 dB/100m
          1000 MHz: 30.9 dB/100m
          1350 MHz: 36.4 dB/100m
          1750 MHz: 41.9 dB/100m
          2050 MHz: 45.8 dB/100m

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          • #50
            Originally posted by VK6UFO View Post
            I can see the moon at night. Pretty sure that's more than 600 km away. 'Line of sight' distance increases significantly with height.

            Maybe, FR24 should install a Flightradar24 Receiver on the Moon. I am sure we will have all corners of the earth properly and uniquely covered.
            F-WSSS1 - Cats refused to Pee & Pooh on RadarBox - Running a FR24 Receiver & DVB-T Dongle 24/7 to piss off The Chief Thief.

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            • #51
              Originally posted by Jarod View Post
              There may not be a best antenna, but there is a best looking antenna.
              http://x264.nl/dump/ads-b-antenna-gr...ane-proper.jpg

              But seriously, all kidding aside, this GP really works well, today i broke my own record:
              http://x264.nl/dump/rtlsdr-mini-virt...1.1-record.jpg

              Parts used:
              BNC Chasis part.
              Copper electrical wire, each piece 6.54cm long.
              Jarod,

              This looks an amazing GP and tracking well in excess of 380nm. 2 Questions if I may?

              1: What did you mount your GP onto?
              2: How high off the ground was it to obtain those nm's?

              Just asking 'coz I'm gonna make one for myself.

              You should patent it :-)
              T-EGBB16

              Hardware: NooElec DVB-T2 Dongle, Raspi Pi2 Mod B, 6dB Collinear Antenna, Nevis Pre-Amp & 1090mhz SAW Filter, 9mtrs WF100 Cable and 28ft Mast.
              Software: Rasbain Jessie Lite, FR24 Feeder, Dump1090mutab and VRS.
              Stats for Mar 18, 2016. Uptime:100%. Aircraft seen:2,012. Positions Reported:486,817. Maximum Distance:243nm (Stats provided by FR24)

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              • #52
                After a good few hours of soldering and a fair amount of 1st degree burns to my fingers. I finally finished building the GP designed by Jarod.

                Well, not entirely as Jarod built for a couple of reasons.

                1: Fingers too sore from getting 1st degree burns from trying to hold copper wire in place whilst soldering.
                2: Whilst the solder happily attached itself to the copper wiring, it would not stick to the Nickel Plated BNC Chassis.

                Therefore, I built a variation of Jarod's design.

                After hours of attempting to solder 9 lengths of copper wire, I instead only used 5.

                1 for the upright centre section and 4 for the chassis bent round the screw holes with a bit of solder in place.

                Whilst I did not gain the 380nm as Jarod did. I did however obtain 90nm with GP just at window height on ground floor of my house. Which was a lot better than the supplied antenna that comes with the dongle at the same height.

                Also, when using 4 copper wires on the chassis, it does provide better range when put into horizontal position instead of the angle suggested by Jarod but remember, Jarod used 8 copper wires on the chassis and not 4 like I did :-)
                T-EGBB16

                Hardware: NooElec DVB-T2 Dongle, Raspi Pi2 Mod B, 6dB Collinear Antenna, Nevis Pre-Amp & 1090mhz SAW Filter, 9mtrs WF100 Cable and 28ft Mast.
                Software: Rasbain Jessie Lite, FR24 Feeder, Dump1090mutab and VRS.
                Stats for Mar 18, 2016. Uptime:100%. Aircraft seen:2,012. Positions Reported:486,817. Maximum Distance:243nm (Stats provided by FR24)

                Comment


                • #53
                  Originally posted by Responder View Post
                  After a good few hours of soldering and a fair amount of 1st degree burns to my fingers. I finally finished building the GP designed by Jarod.
                  how about a picture

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                  • #54
                    As requested.

                    A picture of my variation of the GP Jarod built but with 4 Radials.

                    image.jpg
                    T-EGBB16

                    Hardware: NooElec DVB-T2 Dongle, Raspi Pi2 Mod B, 6dB Collinear Antenna, Nevis Pre-Amp & 1090mhz SAW Filter, 9mtrs WF100 Cable and 28ft Mast.
                    Software: Rasbain Jessie Lite, FR24 Feeder, Dump1090mutab and VRS.
                    Stats for Mar 18, 2016. Uptime:100%. Aircraft seen:2,012. Positions Reported:486,817. Maximum Distance:243nm (Stats provided by FR24)

                    Comment


                    • #55
                      If you want solder to stick to the chassis part of the connector, try filing some of the plating off. That is usually enough. You should apply lots of heat from a good iron before starting to solder.. the body of the connector is like a heatsink.
                      If you have access to flux paste, even better.
                      Another option is to use some brass nuts, bolts and washers through the holes. You can screw the wires down or solder directly to the bolts.
                      Rob, VK6UFO
                      F-YPPH3
                      o410E


                      Comment


                      • #56
                        Thanks Rob,

                        Never thought of attempting to file off some of the plating. I'll give it another go at the weekend :-)
                        T-EGBB16

                        Hardware: NooElec DVB-T2 Dongle, Raspi Pi2 Mod B, 6dB Collinear Antenna, Nevis Pre-Amp & 1090mhz SAW Filter, 9mtrs WF100 Cable and 28ft Mast.
                        Software: Rasbain Jessie Lite, FR24 Feeder, Dump1090mutab and VRS.
                        Stats for Mar 18, 2016. Uptime:100%. Aircraft seen:2,012. Positions Reported:486,817. Maximum Distance:243nm (Stats provided by FR24)

                        Comment


                        • #57
                          Or wind with copper stranding and insert the rod into the centre of the winding and solder to it, so at least a large amount of surface is touched by the winding. (like in a transformer)

                          On my N-plate base like that I simply scratched a bit off and used the existing screw taps and put loops on the radials (they are mostly there for signal reflection anyway)
                          Posts not to be taken as official support representation - Just a helpful uploader who tinkers

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                          • #58
                            We just received this antenna to our office and will perform some tests within the next weeks.
                            http://www.anteni.net/adsb/#!/~/prod...94&id=15504147
                            https://www.dropbox.com/s/2s97kyc9ul...2011.20.29.jpg

                            Comment


                            • #59
                              Originally posted by Mike View Post
                              We just received this antenna to our office and will perform some tests within the next weeks.
                              http://www.anteni.net/adsb/#!/~/prod...94&id=15504147
                              https://www.dropbox.com/s/2s97kyc9ul...2011.20.29.jpg
                              wow.. looks impressive. expensive too! wonder how the range would be like. looking forward to hearing you results in the coming weeks.

                              Comment


                              • #60
                                I guess it consists of 5 units of MS10910 Beam antenna 1090MHz.

                                Each antenna has a beam width of 60 Degree.

                                60 x 5 = 300 Degree.

                                Will it be really Omnidirectional 360 Degree coverage ?
                                F-WSSS1 - Cats refused to Pee & Pooh on RadarBox - Running a FR24 Receiver & DVB-T Dongle 24/7 to piss off The Chief Thief.

                                Comment

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