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  • Originally posted by mickopla View Post
    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
    Connect it second power 'correctly' you could use it as a power extractor - maybe to run one of those flashing LED rear bicycle lights to attach to to the top of the mast as an aircraft warning (i'm just not sure about running a wire up alongside the coco - since it would affect signal)

    .
    .
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    By the way - I'm joking.

    Comment


    • Originally posted by peterhr View Post
      Connect it second power 'correctly' you could use it as a power extractor - maybe to run one of those flashing LED rear bicycle lights to attach to to the top of the mast as an aircraft warning (i'm just not sure about running a wire up alongside the coco - since it would affect signal)

      .
      .
      .
      By the way - I'm joking.
      Peter, this 'joke' is ur 2nd brilliand idea, 1st one being the use of second inserter as dc blocking capacitor.

      If the 2nd inserter is placed at the mast, just below antena, power to flashing LED can be extracted without need to run separate power wire from ground level to mast top.

      Sent from my N762 using Tapatalk 2
      Last edited by abcd567; 2013-12-19, 08:08.

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      • Really need to take the power of at the top of the coco.

        Capacitor to provide the Radio Frequency short circuit from inner to outer

        Two Chokes to take the power from the antenna without affecting the RF (be aware the inner may be positive or negative since the coco switches this around at every stage - so need to check which way around it is)

        Power then goes to a 3v power regulator (this should be able to take say 100mA at 12v and be able supply maybe 350mA at 3v ... if it's an active regulator with small losses. The 3v goes to the bike light.

        ---

        how about lighting the 'weather tube' holding the coco (if it's opaque enough to see the effect, or use a clear PVC tube)
        Last edited by peterhr; 2013-12-19, 10:08.

        Comment


        • Originally posted by peterhr View Post
          Really need to take the power of at the top of the coco.

          Capacitor to provide the Radio Frequency short circuit from inner to outer

          Two Chokes to take the power from the antenna without affecting the RF (be aware the inner may be positive or negative since the coco switches this around at every stage - so need to check which way around it is)

          Power then goes to a 3v power regulator (this should be able to take say 100mA at 12v and be able supply maybe 350mA at 3v ... if it's an active regulator with small losses. The 3v goes to the bike light.

          ---

          how about lighting the 'weather tube' holding the coco (if it's opaque enough to see the effect, or use a clear PVC tube)
          Make one as you have described, and give it a trial run.

          Sent from my N762 using Tapatalk 2

          Comment


          • Originally posted by peterhr View Post
            Really need to take the power of at the top of the coco.

            Capacitor to provide the Radio Frequency short circuit from inner to outer

            Two Chokes to take the power from the antenna without affecting the RF (be aware the inner may be positive or negative since the coco switches this around at every stage - so need to check which way around it is)

            Power then goes to a 3v power regulator (this should be able to take say 100mA at 12v and be able supply maybe 350mA at 3v ... if it's an active regulator with small losses. The 3v goes to the bike light.

            ---

            how about lighting the 'weather tube' holding the coco (if it's opaque enough to see the effect, or use a clear PVC tube)
            The following only applies here in Australia but I would think it would be similar around the world. CASA only requires notification of a mast if it is above 110 metres Above Ground Level (AGL) and then it is for assessment only (by them).

            http://www.casa.gov.au/wcmswr/_asset...139/139c08.pdf

            (see Section 6.3)

            Whether it would require illumination is another matter. I'm proposing a 30' mast at my place next year (hopefully) and was offered a 50 footer, but declined as it wouldnt pass the missus test. This is probably the most important test overall. I wouldnt think too many of us in a residential situation would need worry about either notification or illumination.

            Long story short- no bike light required here, although it's a great idea and it'd be an interesting talking point with the neighbours.

            Regards,
            Gregg
            Last edited by fungus; 2013-12-19, 10:48.
            YSSY2/T-YSSY4 [SBS-1 Basestation w/- SSE-1090 SJ Mk2 Antenna (Thanks Delcomp) ] [Uniden UBCD996T w/- 16 element Wideband Discone VHF/UHF Antenna, and tuned 108MHz-137MHz Airband Antenna] [Trialing a home-brew 1090MHz collinear antenna]

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            • Next time the mast comes down, it's to lengthen it and to install http://www.ebay.co.uk/itm/190988638585 and and HDF400 feed - goodbye home brew coco, amplifier and power injector

              I'm trying to increase my range so I can cover Toronto from Europe
              Last edited by peterhr; 2013-12-19, 11:06.

              Comment


              • Originally posted by peterhr View Post
                Next time the mast comes down, it's to lengthen it and to install http://www.ebay.co.uk/itm/190988638585 and and HDF400 feed - goodbye home brew coco, amplifier and power injector

                I'm trying to increase my range so I can cover Toronto from Europe
                Peter,

                dont throw away the amp and injector just yet, you may still need them. I have a 1090SJ Mkii and still utilise the amp with the injector at the unit (the 'bias-t can be located away from the amp) and it increases my range markedy. Obstacles are the greatest issue here hence the desire to go up another 10' (with no bike light). Good luck covering Europe- it's a fair shot across the ditch

                Regards,
                Gregg
                Last edited by fungus; 2013-12-19, 11:25.
                YSSY2/T-YSSY4 [SBS-1 Basestation w/- SSE-1090 SJ Mk2 Antenna (Thanks Delcomp) ] [Uniden UBCD996T w/- 16 element Wideband Discone VHF/UHF Antenna, and tuned 108MHz-137MHz Airband Antenna] [Trialing a home-brew 1090MHz collinear antenna]

                Comment


                • Originally posted by peterhr View Post
                  Next time the mast comes down, it's to lengthen it and to install http://www.ebay.co.uk/itm/190988638585 and and HDF400 feed - goodbye home brew coco, amplifier and power injector

                  I'm trying to increase my range so I can cover Toronto from Europe
                  Do Antenna like the one linked and the one Fr24 provide to their hosts provide that much of a range increase over a CoCo or homebrew Antenna in general?

                  Comment


                  • I did test the new antenna - it is open-circuit, the the amp might re-appear.

                    I'm amazed - you can (M & F) N type to F adaptors - so fitting the amp to the new collinear would be really easy (the amp has "F- type" females both ends).

                    Originally posted by mickopla View Post
                    Do Antenna like the one linked and the one Fr24 provide to their hosts provide that much of a range increase over a CoCo or homebrew Antenna in general?
                    Don't know, My concern was that I made the coco from some old unknown quality satellite dish cable I had in the shed and assumed a velocity factor of .85 in calculating the element lengths.

                    If the lengths are wrong then the 'saucer' shaped area of maximum sensitivity becomes a cone that can tilt upwards or downwards, depending on if they are too long or two short.

                    I'm hoping that the commercial antenna has been tested and trimmed at the design and prototype stage for maximum sensitivity and the area is flat. The people who made it do understand the issues since they made the Micro-adsb receiver dongle ... I have trust in them ... and the antenna was a bargain (they auction them on Ebay constantly post free worldwide from Bulgaria - often they remain unsold because no one bids.)
                    Last edited by peterhr; 2013-12-19, 11:51.

                    Comment


                    • Originally posted by peterhr View Post
                      .........Don't know, My concern was that I made the coco from some old unknown quality satellite dish cable I had in the shed and assumed a velocity factor of .85 in calculating the element lengths.

                      If the lengths are wrong then the 'saucer' shaped area of maximum sensitivity becomes a cone that can tilt upwards or downwards, depending on if they are too long or two short.

                      I'm hoping that the commercial antenna has been tested and trimmed at the design and prototype stage for maximum sensitivity and the area is flat. ........

                      The gain of a well-designed, well-built 4-element commercial coco is almost equal to the theoretical gain, i.e. 5 dBi in horizontal** direction.
                      Using wrong lengths (due to wrong velocity factor), and poor construction, a home-brew coco may result in a tilted cone, dropping the gain in horizontal direction from 5dBi to say as low as 2dBi, loosing 5-2 = 3dB.

                      So if someone uses home brew, he looses 3 dB and his range is poor. Then he adds an amplifier with a gain of 13 dB, and Bingo!!! the gain of his home brew system is 13+2=15 dB, 3times the gain of the commercial coco.

                      **The direction in which far-off planes are 'seen' by the antenna is near-horizontal.
                      Due to large distance, the signal received from far-off planes is much weaker than signal received from nearby planes.
                      Hence it is highly desirable to have highest gain in horizontal direction.

                      'Saucer' shape radiation pattern gives maximum gain in near-horizontal direction.
                      Tilting the 'cone' reduces the gain in near-horizontal direction (where high-gain is needed most) reducing the range.

                      Comment


                      • Thanks adcd567 for the detailed description.
                        On another note i'm wondering would there be any issues placing two 1090mhz antenna side by side? The reason i ask is today i got approved to host fr24 equipment and understand there is no real way to use their equipment with adsbscope and a like. I plan on keeping my existing set up as i love the whole homebrew scene but wouldn't want it to affect the data i will be sending to fr24.

                        Mike

                        Comment


                        • Originally posted by mickopla View Post
                          Thanks adcd567 for the detailed description.
                          On another note i'm wondering would there be any issues placing two 1090mhz antenna side by side? The reason i ask is today i got approved to host fr24 equipment and understand there is no real way to use their equipment with adsbscope and a like. I plan on keeping my existing set up as i love the whole homebrew scene but wouldn't want it to affect the data i will be sending to fr24.

                          Mike
                          Side by side is ok, provided they are not too close. How much far apart yoy can keep them? I have never used multiple antenna, may be other membersof forum have, and are in better position to advise you. Forum Member '1090MHz' has a tower with multiple antennas. He may give you a practical advise.

                          Sent from my N762 using Tapatalk 2

                          Comment


                          • loss is loss, doesn't matter if you are transmitting a million Watts, or just receiving...

                            Sent using Tapatalk from my ZX81

                            Comment


                            • Originally posted by abcd567 View Post
                              Side by side is ok, provided they are not too close. How much far apart yoy can keep them? I have never used multiple antenna, may be other membersof forum have, and are in better position to advise you. Forum Member '1090MHz' has a tower with multiple antennas. He may give you a practical advise.

                              Sent from my N762 using Tapatalk 2
                              Here is a pic of my current set up. I want to incorporate the fr24 antenna in some way keeping the existing antenna and anemometer.antenna.jpg

                              Comment


                              • Originally posted by Rooster View Post
                                loss is loss, doesn't matter if you are transmitting a million Watts, or just receiving...

                                Sent using Tapatalk from my ZX81
                                True, but you cannot make up for the loss of transmitted power in bad antenna cable & cable joint, except a very costly option: use a more powerful transmitter. It is therefore better to use a low-loss antenna cable & joints.

                                On the other hand you can make up easily for loss of received power in a bad antenna cable & joint by a very low cost solution: add an inline amplifier.

                                Sent from my N762 using Tapatalk 2

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