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  • @gquejada
    Before you start, first get the pigtail. search "MCX to F connector pigtail" on eBay, and you will get huge list of pigtails, with choice of lengths (6", 12" etc) and pigtail cables types (RG174, RG316 etc).

    Pigtail RG174.JPG.jpeg . Pigtail RG316.JPG.jpeg
    Last edited by abcd567; 2014-12-09, 15:02.

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    • @gquejada
      You said you want to use same magnet base for your antenna. This indicates that you want to keep antenna indoors. The range and number of planes will not be good. You will notice a big difference when you move antenna outdoors and above the roof.

      Comment


      • Originally posted by abcd567 View Post
        @gquejada
        Before you start, first get the pigtail. search "MCX to F connector pigtail" on eBay, and you will get huge list of pigtails, with choice of lengths (6", 12" etc) and pigtail cables types (RG174, RG316 etc).

        [ATTACH=CONFIG]5162[/ATTACH] . [ATTACH=CONFIG]5163[/ATTACH]
        Thanks, abcd567!

        These pigtails should allow me to connect to MCX female plug of dongle from whatever antenna I may design for it, am I right?

        How about using this BNC female to MCX male adapter? It should allow me to connect just the same...
        It is found here - http://m.ebay.com/itm/181579423056
        Any special advantage of F connectors over BNC ones, assuming I use the same coax?

        I also found this, straight F connector to MCX plug adapter...http://m.ebay.com/itm/320847600930

        Thanks, again!

        BTW, I came across your Post #1309 on this thread outlining a DIY coax-collinear antenna using RG6. I am going to try that out!

        Comment


        • Originally posted by abcd567 View Post
          Originally posted by K5LEH View Post
          If you didn't power the amp it does nothing for you. In fact it makes it worse. See the diagram in post 1918 that shows dc injector and blocker needed for an amp. As for an antenna, stay with the one supplied with the DVD until you get everything up and running and the amp on line. That gives you a basis for comparison. Some folks are using a discone antenna while others are building a coaxial antenna http://www.balarad.net/ The type of coax is very important since the velocity factor makes the dimensions longer or shorter. Unless you put your antenna vey high and are in a lightening area I would forgo the lightening traps since they add a level of complexity. At least start without it, test, then progress to the traps. Good luck.
          Will have a look on those things, thank you mates and happy Feeding!
          Regards,
          T-EDDE7

          Debian 8 Server | jetvision ADS-B USB Dongle | ADS-B Collinear Antenna
          Banana Pi | Mystique SDR R820T2 | stock Antenna

          Comment


          • Originally posted by abcd567 View Post
            @gquejada
            You said you want to use same magnet base for your antenna. This indicates that you want to keep antenna indoors. The range and number of planes will not be good. You will notice a big difference when you move antenna outdoors and above the roof.
            Hi, again!

            Not necessarily. I intend to bring this indoor antenna outdoors, putting it inside a PET bottle perhaps...
            I wanted to use the same magnetic base so as not to mess up with the MCX connector already on that antenna. I will just change the "whip" on it, making a new WIRE-collinear one for 1090Mhz. Will this change affect the antenna tuning? I picked up the idea from here -
            http://kikuyumoja.com/2014/10/10/how...k-via-piaware/

            This Gentleman collects data for Flightaware... 😊😊😊

            Thanks, again abcd567!

            Comment


            • Originally posted by gquejada View Post
              Thanks, abcd567!

              These pigtails should allow me to connect to MCX female plug of dongle from whatever antenna I may design for it, am I right?

              How about using this BNC female to MCX male adapter? It should allow me to connect just the same...
              It is found here - http://m.ebay.com/itm/181579423056
              Any special advantage of F connectors over BNC ones, assuming I use the same coax?

              I also found this, straight F connector to MCX plug adapter...http://m.ebay.com/itm/320847600930

              Thanks, again!

              BTW, I came across your Post #1309 on this thread outlining a DIY coax-collinear antenna using RG6. I am going to try that out!
              (1) Using BNC & F are alternates to each other. Any one is ok. I use F type because in North America, it is used for Cable TV, and its accessories are readily available even in small stores, and are very cheap. Also most of in-Line Amplifiers, power inserters, DC Blockers etc have F-Female Type connectors.

              (2) DO NOT use the element length shown in post 1309. It is a FAILED experiment as subsequent trial runs by me and 2 other forum members have proved. The excellent result I got on the very first trial shown in this post was due to extraordinary weather & atmospheric conditions.

              Instead, calculate element length by formula "Element Length = Velocity Factor of Coax Cable x 275/2". Check specifications/data sheet of your cable to find Velocity Factor.

              If you do not have data sheet/specs, then try these Velocity Factors:

              For Coax Cable with Foamed PolyEthylene insulation, also known as FPE insulation, V.F. = 0.83 (use it for RG6 coax as most manufacturers of RG6 coax use FPE insulation). This will give you element length of 114 mm.

              For Coax Cable with PolyEthylene insulation, also known as PE insulation, V.F. = 0.66 (use it for RG58 coax most manufacturers of RG58 Coax use PE insulation). This will give you element length of 91 mm.

              However the exact value varies from manufacturer to manufacturer & model to model.
              Last edited by abcd567; 2014-12-09, 17:01.

              Comment


              • Originally posted by gquejada View Post
                Hi!

                Talk about being new in the forum... I just signed up/registered. This is my very first Post! I've read what I could about the Forum Rules. To read thru the 194pages of this thread on "Best Antenna" is also a bit daunting... plus a lot of the technical details mentioned in the posts is just way above my understanding, for now. I am slowly learning.
                Well done wading through almost 2000 posts. As you say a lot of useful information but it can be difficult to tease out the important bits.

                Two simple to make antennas are:-
                1) the "cantenna" http://forum.flightradar24.com/threa...ll=1#post55629
                2) the dipole http://forum.flightradar24.com/threa...ll=1#post56008 Build one without the amplifier first!

                They both give better results than the supplied whip.
                The Coax Collinear has proved to be a difficult character Making one is quite simple but results have proved to be very variable even with known Velocity Factor.
                Last edited by trigger; 2014-12-09, 17:02.
                T-EGUB1

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                • Originally posted by gquejada View Post
                  ........I plan to use the same magnetic foot the generic antenna has (on i think RG174) and make a new WIRE-collinear one for it designed for the ADS-B frequency. Would this be "better" on the same RG174 coax? How about the 1/4wave GP antenna? This design looks doable for me too... I intend to do both antennas so I can compare.

                  Any suggestion/help would be appreciated from the veterans on this thread... ;-) Thanks!

                  Originally posted by trigger View Post
                  Well done wading through almost 2000 posts. As you say a lot of useful information but it can be difficult to tease out the important bits.

                  Two simple to make antennas are:-
                  1) the "cantenna" http://forum.flightradar24.com/threa...ll=1#post55629
                  2) the dipole http://forum.flightradar24.com/threa...ll=1#post56008 Build one without the amplifier first!

                  They both give better results than the supplied whip.
                  The Coax Collinear has proved to be a difficult character Making one is quite simple but results have proved to be very variable even with known Velocity Factor.
                  Yes I agree with trigger. CoaxialCollinear (CoCo) is very alluring at first glance due to it is easy to construct and needs only a length of coax. It shows the problem only after it is built and tried. This mainly originates from not knowing the Velocity Factor, and therefore using inaccurate value, and getting poor performance as a result. Another factor is inaccuracy in making.

                  Here is the simpler indoor version of Cantenna if some one want to try: http://forum.flightradar24.com/threa...ll=1#post53094

                  Outdoor version is give in trigger's above quoted post

                  Comment


                  • Originally posted by gquejada View Post
                    ........How about using this BNC female to MCX male adapter? It should allow me to connect just the same...
                    It is found here - http://m.ebay.com/itm/181579423056.......

                    ....I also found this, straight F connector to MCX plug adapter...http://m.ebay.com/itm/320847600930......
                    [ATTACH=CONFIG]5164[/ATTACH] . [ATTACH=CONFIG]5165[/ATTACH]

                    Both of these connector are connected directly to heavy coax like RG6 & RG58. The weight & stiffness of these heavy coax can ultimately damage the MCX socket of the DVB-T USB.

                    The pigtails use thinner & softer intermediate cable pieces between MCX & F/BNC to prevent stress of heavy RG6, RG59, RG58 cables to reach the USB's mcx socket.
                    Last edited by abcd567; 2014-12-09, 22:08.

                    Comment


                    • Originally posted by trigger View Post
                      ..........The Coax Collinear has proved to be a difficult character Making one is quite simple but results have proved to be very variable even with known Velocity Factor.
                      The CoCo is "love at first sight→ quick matriage→ divorce" "Marry in haste, repent later" as the saying goes.

                      Comment


                      • Originally posted by abcd567 View Post
                        The CoCo is "love at first sight→ quick matriage→ divorce" "Marry in haste, repent later" as the saying goes.
                        Much like before getting married, I should sincerely heed the advice of the already married ones! "Did that, done that" as another saying goes...

                        But what about WIRE collinear ones? I seem to be "in love at first sight" with this beauty...

                        Comment


                        • Originally posted by gquejada View Post
                          Much like before getting married, I should sincerely heed the advice of the already married ones! "Did that, done that" as another saying goes...

                          But what about WIRE collinear ones? I seem to be "in love at first sight" with this beauty...
                          I have never tried wire collinear. Give it a try as it is easy to make. It should be better than antenna supplied with the DVB USB. But dont get frustrated if results are not upto your expectations.

                          All collinears are very sensetive to dimensions. Any error in design or construction can knock out the collinear. This applies to your selected type (collinear whip with coil as phasing element), Franklin collinear with hairpin as phasing element, & coaxial collinear with core wire as phasing element (shield is radiating element)

                          The coaxial collinear is worst in this respect as it involves insulation. Use of inaccurate VF to calculate length affects it substantially. Also the shielding is never 100%, and cheaper the cable, poorer is the shielding. Poor shielding also affects performance of coco.
                          Last edited by abcd567; 2014-12-10, 00:23.

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                          • @gquejada
                            Do not get discouraged by what I have written in my previous post. We all have passed through this: trying a design, bad result, discarding, trying another design or remaking the same design. We did this again and again.

                            I had to make 7 cocos to get an acceptable one. In addition I have made two 1/2 wavelength dipole, one fullwave dipole, one 5/8 wave dipole, two Franklin collinears, several coiled dipoles, and several sleeved dipoles (Cantenna).

                            DIY Antenna is not costly, only cheap materials, effort & time. So discarding an antenna and going for another one is easy (but frustrating for most novices).

                            Try many designs and builds, and finally settle for one which proves best for you. There is no universal antenna which is best for every one.
                            Last edited by abcd567; 2014-12-10, 01:46.

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                            • @equi , my amazon.de shopping list:

                              - Amplifier
                              - Power injector
                              - DC blocker
                              - self amalgamating tape

                              The antenna is from Jetvision.de

                              Comment


                              • Awesome, thank you
                                Regards,
                                T-EDDE7

                                Debian 8 Server | jetvision ADS-B USB Dongle | ADS-B Collinear Antenna
                                Banana Pi | Mystique SDR R820T2 | stock Antenna

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