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  • Originally posted by STR_EDDS View Post
    nice, i think i hit theoretical maximum
    [ATTACH=CONFIG]5510[/ATTACH]
    What the blue line shows? Is it plot by "HeyWhatsThat.com"? Black line seems to show your maximum range by DVB-T Dongle+Franklin.

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    • blue line is plotted by "HeyWhatsThat.com", 30.000 feet

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      • Originally posted by STR_EDDS View Post
        [ATTACH=CONFIG]5494[/ATTACH]
        Hi STR_EDDS,

        What is this tower and where is it? Is it part of your home? It's a great location for antennas !
        www.ADS-B.ca

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        • Originally posted by 1090 MHz View Post
          Hi STR_EDDS,

          What is this tower and where is it? Is it part of your home? It's a great location for antennas !
          Its an old tower from 1896, no way to mount an antenna there, its protected by "protection of historical monuments"
          http://translate.google.de/translate...urm&edit-text=
          Last edited by STR_EDDS; 2015-01-23, 02:44.

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          • STR_EDDS....If I can see your antenna was so close to chrome pipe handle.Reception would be better if kept away from it ,reckon.Anyway, very crafty look like factory made! Well done!

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            • Originally posted by LDSP View Post
              STR_EDDS....If I can see your antenna was so close to chrome pipe handle.Reception would be better if kept away from it ,reckon.Anyway, very crafty look like factory made! Well done!
              You are right. To avoid reduced performance, antenna should be away from metal objects. As a bare minimum, it should not be less than one wavelength away (30 cm / 1 ft in adsb case).

              You are very observant. Thanks for pointing out. I checked again the photos STR_EDDS has posted. The lowest leg of Franklin is not only close, but looks as if is touching the chrome handle (in this case chrome handle is antenna's part now and affecting Gain & SWR). Also the lowest leg's entire length is behind the wall blocking adsb signal to lowest leg from the direction of wall. Anyway, even with these things, the STR_EDDS 's Franklin gave good performance.
              Last edited by abcd567; 2015-01-26, 18:34.

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              • i put it there only for the pictures
                for the tests i raised the antenna in the air with my hands.

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                • Originally posted by STR_EDDS View Post
                  i put it there only for the pictures
                  for the tests i raised the antenna in the air with my hands.
                  Wow, you stood at top of tower holding antenna in your hand for 15 minutes in this freezing temprature & wind!! I will quit in less than 5 minutes.

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                  • Originally posted by abcd567 View Post
                    @charan:

                    Another Amplifier circuit from Infineon (Siemens), one of the manufacturers of transistor BFP420

                    Source: http://www.infineon.com/dgdl/AN018.p...1427688a990761

                    [ATTACH=CONFIG]5334[/ATTACH] [ATTACH=CONFIG]5335[/ATTACH]
                    Hello back again ! I got BF420 from local website. so i made this lna https://blackbirdengineering.files.w...013/05/lna.png and result is stunning.! haha better reception without lna..
                    i made exactly as shown in circuit (trust me) except for powering up from coaxial i removed C2 and R2 and placed them near receiver and powered it with 5.22V.fm with pwer.jpg <- this is with power and see what happens when i disconnected power (but not lna) with out pwer.jpg


                    Please help im getting headache with these !
                    RTL SDR : T-VEVZ1

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                    • A 6 element Franklin recently built by "Karin" - Nice built!

                      Karin-P1260120a.jpg . Karin-P1260119a.jpg

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                      • @ charan:

                        (1) You are testing at FM frequency 93.5 Mhz instead of ADSB freq. 1090 MHZ

                        (2) At high frequencies like ADSB, printed circuit board layout or connection wiring plays a significant role. Did you use the printed board layout shown on the web page https://blackbirdengineering.wordpre...lna-for-ads-b/ ?

                        Comment


                        • Originally posted by abcd567 View Post
                          @ charan:

                          (1) You are testing at FM frequency 93.5 Mhz instead of ADSB freq. 1090 MHZ

                          (2) At high frequencies like ADSB, printed circuit board layout or connection wiring plays a significant role. Did you use the printed board layout shown on the web page https://blackbirdengineering.wordpre...lna-for-ads-b/ ?
                          I got it working ! yay.... contact issue.. but yes i want it for Airband so testing with FM but now got another problem FM is interfering with airband.... every where FM only from around 70mhz to 160mhz :/ ! can you please give circuit for BFP420 for airband ? ill shift this for ADS-B and will let you know the results soon !!!! ( seems like this specified circuit is for ADS-B only).!
                          RTL SDR : T-VEVZ1

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                          • @charan:
                            You need to add filter at input of amplifier to reject FM and other TV and communication VHF bands. A band-pass filter for air band will reject frequencies higher & lower than air band and pass only air band to amplifier.

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                            • Originally posted by abcd567 View Post
                              @charan:
                              You need to add filter at input of amplifier to reject FM and other TV and communication VHF bands. A band-pass filter for air band will reject frequencies higher & lower than air band and pass only air band to amplifier.
                              Oh thanks !
                              RTL SDR : T-VEVZ1

                              Comment


                              • Originally posted by abcd567 View Post
                                @charan:
                                You need to add filter at input of amplifier to reject FM and other TV and communication VHF bands. A band-pass filter for air band will reject frequencies higher & lower than air band and pass only air band to amplifier.
                                Or a cheaper option would to be add "notch filters" to the offending frequencies, these can be made from simple open ended coax cables...

                                http://www.changpuak.ch/electronics/...r_Designer.php

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